Space Sunday: Artemis 2: around the Moon, home again – and beyond!

We see you: Christina Koch looks out of one of the Orion capsule’s windows towards a GoPro camera mounted on one of the four forward-swept solar array wings of the vehicle’s European Service Module (ESM). To her right, she is holding aloft the mission’s zero-gee indicator / mascot, “Rise”. Created by a 3rd grader, “Rise” has a smiley-faced Moon and is wearing a blue-and-green cap representing Earth, all in a homage to the famous Apollo 8 “Earthrise” photo. Credit: NASA

On Wednesday April 1st, 2026, NASA’s Artemis 2 mission launched on a 10-day cruise to the Moon and back (with time initially spent in Earth orbit), carrying a crew of four to test the capabilities and facilities of the Orion Multi-Purpose Crew Vehicle (MPCV). The mission was a key preparatory step to send crews to the surface of the Moon, starting with the flight of Artemis 4, currently targeting a 2028 launch.

In the first part of this 2-part series I covered Artemis 2 from launch to TLI. Here I complete the voyage in summary form.

Whilst marked by a number of on-going space health experiments, video calls to Earth and performing sundry tasks and s few minor fixes, the outward trip from Earth to the Moon was pretty much a claim affair. A 17.5 second mid-course correction manoeuvre was performed automatically by Integrity, the Orion spacecraft, on mission day 5 – which was actually the first to be performed, the initial correction burn having been cancelled due to Integrity being so precisely on course whilst under its own flight control software.

Taken in high Earth orbit, this image shows the European Service Module and its main engine, with the Earth as a backdrop as the motor is test gimballed ahead of the TLI burn to send Integrity to the Moon. Captured by a solar-panel mounted GoPro camera. Credit: NASA

Day five also saw the crew test their dual-purpose Orion Crew Survival System (OCSS) suits – the orange-coloured space suits the crew wore during the Artemis 2. Designed for quick donning, the suits function as a contingency safety system during the crew’s time aboard and Orion spacecraft, providing up to 144 hours of life support in the event of a cabin depressurisation.

Artemis 2 astronaut Christina Koch poses in her custom-made OCSS suit ahead of the Artemis 2 mission. Credit: NASA.

In their second role, the suits are intended to act as water survival suits in the event of an emergency evacuation of an Orion vehicle post-splashdown. In this role, the suits are intentionally coloured “international orange” so as to be more clearly visible in the water – just like survival suits used on ocean-going cargo vessels, oil rigs, deep sea fishing vessels, etc They additionally have inbuilt flotation devices. Each OCSS is custom made to fit an individual astronaut.

Day five also saw a series of discussions with Mission Control on the upcoming loop around the Moon to review lunar surface targets for observation and photography during the flyby and finalise observation techniques.

On flight day 6, Integrity officially entered the influence of the Moon, with lunar gravity now the dominant force in shaping the vehicle’s trajectory. Until now, Integrity had effectively (if slowly) been decelerating, due to the “pull” of Earth’s gravity behind it, effectively cruising at a few thousand kilometres an hour at it approached the Moon. Now, under the Moon’s influence the craft would start to very slowly accelerate, allowing the Moon’s gravity to swing it around the Moon and lob it back towards Earth without any significant engine burns.

In 1968, the crew of Apollo 8, the first humans to fly around the Moon, captured an iconic image of Earth “rising” over the Moon as the Apollo CSM re-emerged from being on the Moon’s far side. On April 6th, 2026, and 57 years later, the crew of Artemis 2 captured this image of a crescent Earth “setting” over the Moon as their Orion spacecraft started its journey around the Moon’s far side. Credit: NASA

Around the Moon

At 23:00 UCT on April 6th, Artemis 2 made its closest approach to the Moon, passing some 6,545 kilometres above the Moon’s far side. Shortly thereafter Integrity reached a distance of 406,771 kilometres from Earth, breaking the record for the furthest any humans had been from Earth and set by the crew of Apollo 13 in 1970. At this point, Integrity officially started its flight back towards Earth.

During the loop around the Moon, Artemis 2 was in communications black-out with Earth due to the bulk of the Moon being between the spacecraft and Earth, effectively blocking all signals. This blackout lasted 40 minutes, and ended with a successful recovery of comms and telemetry at the expected time.

A gif showing the solar eclipse as seen from deep space by Artemis 2. Credit: NASA

Following the comms blackout, the crew of Artemis 2 witnessed a solar eclipse from deep space as the bulk of the Moon came between them and the Sun. This allowed the crew to observe both the eclipse from a unique perspective, and witness a number of “impact flashes” of meteoroids striking the semi-dark lunar surface facing them. The Moon was not fully dark as the Earth was off to one side relative to Integrity, and so was reflecting sunlight back onto one hemisphere of the Moon, bathing it in “Earthlight”.

Also during the flight around the Moon, the crew christened two previously unnamed craters on the Moon. They named one for their spacecraft, Integrity, whilst the second was – in a poignant moment – named Carroll, in honour of Reid Wiseman’s late wife, who passed away from cancer in 2020.

Artemis 2 crew Commander, Reid Wiseman with his late wife, Carroll, after whom the crew named a crater on the Moon.

Between flight day 7 and flight day 9, Orion departed the Moon’s sphere of influence on its free return trajectory towards Earth, once again slowly accelerating. For most of Day 7 the crew were engaged in debriefing calls with Earth, recording their observations, feelings and emotions during their trip around the Moon whilst memories and reactions were still fresh. They also put in a call to astronauts aboard the International Space Station (ISS).

A further planned use of manual control by Wiseman and Pilot Victor Glover on Day 8 was cancelled in order to allow mission managers conduct a data-gathering exercise related to a non-critical helium leak within the Orion’s European Service Module (ESM), so that they might better analyse the issue post-mission. Two final trajectory adjustment burns were carried out on Days 9 and 10, lasting 8 and 9 seconds respectively. Most of Day 9 saw the crew packing and stowing experiments and equipment in readiness for re-entry and splashdown.

Following the course correction burn on Day 10, the ESM was jettisoned, its work done. The reaction control thrusters system (RCS) on Integrity then operated in sequence over 19-seond period, both manoeuvring the capsule away from the ESM and orienting it in readiness foe atmospheric re-entry.

A gif showing solar panel GoPro camera views of Integrity’s crew capsule sparating from the European Service Module in readiness for re-entry. Credit: NASA

EDS: Entry, Descent and Splashdown

Day 10 saw the most critical elements of the mission unfold: atmospheric entry, descent and splashdown. During Artemis 1, and as I’ve covered in numerous Space Sunday pieces, post-recovery, the heat shield showed some disturbing issues. As well as the expected ablation damage to the heat shield, it also showed signed of deep scoring and charring, with relatively large holes apparently seared through the heat shield material.

After extensive analysis, it was determined that an error in the fabrication process for the initial heat shields for Artemis 1 through 3 had resulted in pockets of gas being trapped in the layers of ablative material. Due to the original re-entry profile for Orion, as used on Artemis 1, which saw the vehicle “skip” in and out of the upper atmosphere to reduce its velocity prior to actual re-entry, these gases ended up being super-heated several times, weakening the heat shield’s structure and eventually blowing holes up and out of it as they outgassed.

While the fabrication process for the heat shields was revised to mitigate any issues of gases becoming trapped – Artemis 2, due to time constraints, would have to fly with its original heat shield. To compensate for this, NASA altered the mission’s re-entry profile to be more Apollo-like: a single direct re-entry. Whilst this might increase stresses on the vehicle and crew, it would reduce the time over which any trapped gases in the heat shield might have expand and contract and weaken its overall integrity, thus increasing the risk of failure.

As it turned out, the heat shield (subject to post-flight inspection) did its job in this new re-entry profile and protected Integrity and its crew, all of which descended by parachute post re-entry to splashdown off the coast of California, where a recovery operation overseen by the USS John P. Murtha out of San Diego saw the recovery of both crew and the space vehicle. Following initial medical checks on the Murtha, the four crew were then flown to the mainland for further check-ups, prior to proceeding on to the Johnson Space Centre in Texas to be reunited with families and loved ones.

The Artemis 2 crew at Johnson Space Centre, April 11th, 2026. (l to r): Jeremy Hansen (CSA); Christina Koch (NASA); Victor Glover (NASA) and a triumphant-looking Reid Wiseman (NASA), holding “Rise” the mission’s zero-gravity indicator and mascot. Credit: NASA

Research related to Artemis 2 will continue post flight, and some of it will continue to focus directly on the four crew, comprising functional check-out tests, simulated space walks, exercises, etc., to further gain insight into the human body’s ability to adapt to low gravity operations and work, and its ability to recover from them. As well as this, all four will be a part of a media circus for some time to come. To them, and all those involved in Artemis and Artemis 2 – congratulations.

What Comes Next?

Originally, Artemis 2 was to be followed by the first attempt at landing an Artemis crew on the Moon. However, this idea both spoke to an unwarranted gung-ho attitude on the part of Artemis management at NASA (no crewed pre-testing of the lunar landing system (called the Human Landing System, or HLS) in Earth orbit), and assumed the mission would actually have a lunar landing vehicle (from SpaceX) available to meet its 2027 launch date.

Blue Origin’s Blue Moon Mark 2 HLS (l) and SpaceX Starship HLS – NOT to scale. The Blue Origin vehicle is 16 metres high as benefits a low centre of mass – crew compartment, engines electronics, etc, all at the base of the vehicle, which includes broad-set landing legs for stability. The SpaceX design – 52 metres tall – suffers from a high centre of mass: crew compartment, electronics, batteries, engines all in the upper third of the vehicle, requiring an elevator (single point of failure) to get crews to / from the surface on the Moon, and a comparatively narrow-set landing legs, further increasing vehicle instability when landing on an unprepared surface like the Moon.

In taking over at NASA, Jared Issacman saw the gung-ho approach of Artemis 3 as a step too far, and so  – with Congressional and White House approval – determined Artemis 3 should be an Earth-orbiting testy of the HLS vehicle by a crew. Also, in keeping with his predecessor, Sean Duffy, he indicated that SpaceX was no longer the sole provider of the Artemis 3 HLS; but would directly face off against Blue Origin, who had been awarded a HLS contract by order of Congress after NASA changed the scope and rules of the original HLS contract to favour SpaceX.

Given that the SpaceX HLS continues to exist as little more than a few disparate elements (such as the crew elevator – largely developed by NASA) and pretty computer renderings, this move to include Blue Origin – who are actively testing elements of their HLS, Called Blue Moon Mark 2 with NASA astronauts – is a wise one, given the SpaceX CEO appears to believe time frames and delivery dates are purely functions of his ego.

A full scale mock-up of the Blue Origin Blue Moon Mark 2 crew section with airlock undergoing testing for astronaut egress / ingress and the recovery of an incapacitated crew member, using the neutral buoyancy facility at NASA’s Johnson Space Centre. Credit: Blue Origin / NASA

As it is, this year should see Blue Origin fly a Blue Moon “pathfinder” mission to the Moon. This will see a scaled-down version of the Blue Moon cargo lander fly a payload from NASA to the Moon, allowing it to test the flight control, navigation, and data communications systems and avionics which will all be part of both the Blue Moon Mark 1 cargo vehicle and Blue Moon Mark 2 HLS. If successful, the mission could put Blue Origin in a strong position to provide the HLS vehicle for both Artemis 4 and Artemis 5.

However, even if one (or both) HLS vehicles get successfully tested in Earth orbit in 2027, it does not mean NASA will be ready to send astronauts to the lunar surface – there is another hurdle to overcome, one entirely of NASA’s own making: cryogenic orbital refuelling.

To explain: while techniques for transferring hypergolic propellants between space  craft has long been available (the ISS, for example, routinely takes on propellants for its manoeuvring thrusters), cryogenic propellant transfer in space is entirely new. It’s not been used before simply because cryogenic propellants are not exactly stable. For one thing, they don’t like heat (and in space, in direct sunlight it s very hot). Heat makes them revert to a gaseous state, expanding their volume. This puts greater and greater pressure on the tanks holding them, such that if the gas isn’t vented to some degree, everything is going to quickly vanish in a brilliant (if silent – in space, no-one can here you go pop!) explosion.

Renderings like this showing one vehicle (in this case a SpaceX Starship (uppermost) transferring propellants to another may look good, but the fact is, such transfers have never been tried in space and are far more complex than hypergolic propellant transfer and storage. Credit: SpaceX

Cryogenic propellants are also heavy in their liquid state, making them somethings of a deadweight if you’re attempting to lift them to orbit rather than burning them as a means to get to orbit. This latter point means that in order just to get to Earth orbit or to the Moon, the SpaceX HLS and Blue Moon Mark 2 (respectively) must launch without the fuel needed to get to the Moon, land a crew and get them back to lunar orbit. Thus, the fuel must be ferried to them post launch.

For Blue Origin, this means launching a Blue Moon HLS to lunar orbit, but without the propellants it needs to operate between lunar orbit and the Moon’s surface. Instead, these must be delivered by a “tanker” craft called the Cislunar Transporter, being developed by Lockheed Martin. But here’s the catch: the Cislunar Transporter has to be launched without the propellants it needs to get to the Moon or those it must transfer to the waiting HLS. So, once in orbit it also has to be “refuelled” by at least two Blue Origin New Glenn rockets.

And if that sounds complicated – SpaceX much do much the same with their HLS, which will launch with only sufficient propellants needed to get to Earth orbit. After this it must either make up to sixteen individual dockings with Starship “tankers” to take on the propellants it needs to reach the Moon and perform its duties there, or it must rendezvous with a (also yet to be built) “orbital fuel depot” previously filled with the propellants it needs by multiple Starship “tanker” flights.

And this is where boil-off comes into play: all of these approaches will result in large volumes of cryogenic propellants spending a lot of time in direct sunlight, turning back to a gaseous state, expanding and requiring venting to prevent their storage tanks rupturing. So techniques and entirely new technologies need to be developed and tested in order to reduce the overall boil-off issues lest more time is spent on “tank top-up” missions than in actually sending humans to the Moon. Further, no-one knows if large volumes of cryogenic propellants can easily be pumped from one vehicle to another in microgravity.

Thus, even though Artemis 2 has been a huge success and NASA is turning its attention to Artemis 3, the programme as a whole still has some hefty hurdles to clear before it is close to being ready to send humans back to the surface of the Moon, and at the current rate of progress, I cannot see all those hurdles being cleared by “early 2028 – less than 2 years from now – when Artemis4 is supposed to launch on its crewed mission to the lunar surface.

Space Sunday: Artemis 2: from launch to TLI

Ignition of the four RS-25 engines on the Artemis 2 SLS, several seconds before the ignition of the two Solid Rocket Boosters (SRBs) seen either side of the SLS core stage, take from a protected camera in the base of the Mobile Launch Platform. Credit: NASA

On Wednesday April 1st, 2026, NASA’s Artemis 2 mission launched on a 10-day cruise to the Moon and back (with time initially spent in Earth orbit), carrying a crew of four to test the capabilities and facilities of the Orion Multi-Purpose Crew Vehicle (MPCV) when used for human spaceflight.

The mission marks a number of firsts for NASA, all critical to future Artemis missions, including:

  • The first launch of a Space Launch system (SLS) rocket with a crew aboard.
  • The first launch of the Orion spacecraft – this one christened Integrity by its crew – with people aboard.
  • The first time an Orion spacecraft has flown under manual control.
  • The first time an Orion vehicle will attempt a re-entry into Earth’s atmosphere carrying a crew aboard.
  • The first time humans have surpassed 400,000 kilometres from Earth.
  • The first time a vehicle intended for use in the vicinity of the Moon has carried an actual toilet on board.
  • The first time a non-US citizen has travelled to the Moon.

The four crew in question are Mission Commander Reid Wiseman, Mission Pilot Victor Glover, Mission specialist Christina Koch (pronounced “Cook”), all from NASA, and Mission Specialist Jeremy Hansen of the Canadian Space Agency. If you’re interested in potted histories of the crew’s backgrounds, then please refer to my previous Space Sunday article.

The four crew of Artemis 2 department the Armstrong Building at Kennedy Space Centre, Florida. (l to r): MS Jeremy Hansen; Pilot Victor Glover; Commander Reid Wiseman; MS Christina Koch. Credit: NASA

Launch

Lift-off came at 22:35 UTC, some 11 minutes later than the target launch time after a couple of minor issues on the SLS vehicle had to be investigated and resolved. One of these related to one of the two battery systems powering the Flight Termination System. The latter is used to destruct the rocket once the crew have been pulled clear by the Launch Abort System (LAS), should a serious issue result in the rocket veering substantially off-course. This particular problem was identified as a sensor failure rather than any fault with the battery itself.

The power of the SLS was immediately apparent following launch – at just thirty seconds into the flight, the launch system has completed its roll to pitch over to the correct ascent angle and was punching through 4.8 kilometres altitude as a speed in excess of 1,920 km/h.  From there:

In just 30 seconds after launch, Artemis 2 was almost 5 kilometres above the Earth and accelerating rapidly. Credit: NASA
  • At T+1 minute the vehicle passed through ”Max Q”, the period when the rocket encounters the peak atmospheric dynamic stresses as it continues to accelerate through the denser portion of the atmosphere, the four RS-25 motors of the core stage throttling back to reduce the load on the rocket.
  • At T+ 90 seconds, with Max Q passed and the RS-25 motors running at 100% thrust, the SLS went supersonic and passing through 22.4 km altitude.
  • At T+2 minutes, with the RS-25 motors had again throttled to 85% thrust, and the two massive solid rocket boosters, their fuel expended, separated to continue on their own ballistic trajectory, eventually falling into the Atlantic Ocean.
  • By 3 minutes into the ascent, Artemis 2 was at 78.4 km altitude, and closing on the 80 km Kármán line, the conventional definition of “the edge of space”. Travelling at some 8,000 km/h, the rocket jettisoned the two fairings that had protected Integrity’s European Service Module (ESM).
  • This was followed almost immediately by the unlocking of the couplings between the LAS at the top of the rocket, and the Orion capsule. The motors on the LAS fired, pulling it clear of the SLS, exposing the Orion capsule to space.
Captured via a film camera mounted on one of NASA observation aircraft, this still shows the SLS rocket of Artemis 2 with its main engines running at full power, together with the separated Solid Rocket Boosters, ESM protective Fairings and the LAS tower, as they part company from the rocket to commence their destructive falls into the Atlantic Ocean. Credit: NASA – Click for full size
  • MECO – main engine cut-off – occurred at 8 minutes 2 seconds after lift-off, with Integrity and the Interim Cryogenic Propulsion Stage (ICPS) continuing to ascend, the reaction control systems (RCS) on the ICPS sufficient to pull it and Integrity clear of the SLS core stage, which, like the SRBs, continued on its own ballistic trajectory, prior to starting a long fall back to Earth, breaking up in the process and falling into the Atlantic Ocean.

At this point, Integrity was travelling at 27,200 km/h – slightly above the speed required to achieve Earth orbit and on a trajectory intended to put it into an elliptical orbit around Earth with a perigee (closest point to Earth) of around 200 km. At this point, operations switched from launch to initial mission activities.

A rear-facing camera on the Orion capsule capture another view of the ESM fairings being separated (centre bottom and (just visible) centre top). Credit: NASA

The latter comprised two major elements: inside the Orion capsule, Christina Koch and Jeremy Hansen left their seats to set-up critical equipment and services. These included unstowing the fire-fighting equipment and mounting it on its assigned racks and then doing the same with the drinking water dispenser, toilet (which had its first malfunction, requiring Koch and Hansen to carry out a fix (the Toilet would again have issues on Flight Day 4, with the crew reporting it was depositing unpleasant odours in the main capsule) and other crew-related equipment. At the same time, Wiseman and Glover remained in their seats and ran through the protocols and check sheets for deploying the ESM’s solar arrays – vital for supplying Integrity with electrical power.

The solar arrays were deployed some 25 minutes after launch, and powered-up to start producing electrical power. At 50 minutes after lift-off, Hansen and Koch were back in their seats, the solar arrays were producing power and the go was given for two orbit-changing manoeuvres.

One of Integrity’s four deployed solar arrays with Earth as a backdrop, as seen from a camera mounted on one of the other solar arrays. Credit: NASA

The first was a short burst of the ICPS RL-10 engine, raising the perigee of Integrity’s orbit whilst maintaining its elliptical form. This was followed by a second 15-minute burn of the RL-10, extending Integrity’s perigee and apogee (the latter to some 70,000 km from Earth, placing the vehicle in a high Earth orbit.

This second RL-10 burn expended almost all remaining fuel in the ICPS, accelerating Integrity almost to the velocity required to complete a trans-lunar injection (TLI) manoeuvre. However, this is not what happened. Instead, with the ICPS separated and orbiting Earth independently of Integrity, Glover and Wiseman commenced what NASA normally refers to as an RPOD simulation, but which for Artemis 2 was simply called “proximity operations”.

RPOD Simulations / Proximity Operations

RPOD – Rendezvous, Proximity Operations and Docking – is a core part of modern day space operations with NASA, being fundamental to crews and supplies being able to launch to and reach the International Space Station (ISS) and then dock safety with it either under automated or manual control.

For the Artemis programme, being able to carry out a successful RPOD is vital to all the lunar surface missions, as they must be able to rendezvous and temporarily dock with the Moon- orbiting Human Landing System (HLS) vehicle which will actually deliver nominated crew members to the surface of the Moon, and then re-dock with the HLS vehicle to allow the surface mission crew return to their Orion craft for a return to Earth.

A conceptual rendering of Integrity performing a simulated RPOD with its ICPS as part of the proximity operations. Thee “docking target” can be seen within the open end of the ESM adaptor fairing. Credit: ESA

To this end, the ICPS had been equipped with a rendezvous and docking target, allowing Wiseman and Glover to test out the docking heads-up display whilst also using Integrity’s RCS thrusters to make simulated rendezvous approaches to the ICPS, aborting before the two vehicles actually made contact. In addition, Wiseman and Glover used manual control of the Orion to test proximity manoeuvring and close formation flying around the ICPS – both the POD and proximity operations marking the first time Orion had ever been manually flown. Both astronauts praised the vehicle’s handling qualities prior to returning the craft to its autopilot.

With Integrity well clear of the ICPS, the latter deployed two CubeSats then fired its RL-10 for a final time, placing it on a destructive re-entry into the upper atmosphere. At this point the crew moved to the next phases of initial operations.

Initial Mission Highlights

First, the Orion’s “gymnasium” – a flywheel device capable of allowing multiple exercises – was set-up and crew members took it in turns exercising, putting Integrity’s life support system through something of a stress test. After this, the crew set-up the food reheater and had dinner together from their rather impressive menu of meal choices. A 4-hour sleep period was then taken, allowing the crew some much needed rest.

Artemis 2 is providing unprecedented coverage, with 2/7 livestreams from the vehicle, frequent mission updates and interviews with the crew – such as this one from Saturday, April 4th, 2026. Form l to r: Reid Wiseman, Jeremy Hansen, Christina Koch and Victor Glover. Credit: NASA / AP

The sleep period was short as a further orbital manoeuvre was required to again raise Integrity’s perigee away from Earth and place it on a trajectory suitable for a TLI burn. With this complete, the crew settled back for another 4-hour sleep period whilst NASA mission control reviewed the overall performance of Orion and its systems to determine if Integrity was good to go for a free-return flight for the Moon.

Authorisation was given for TLI on flight day 2 after the crew had risen and eaten. The manoeuvre comprised a burn of the ESM’s AJ10 main engine of just under 6 minutes, using some 450 kg of hypergolic propellants. It pushed Integrity out of Earth’s orbit and on its way to pass around the Moon. This free return trajectory meant the vehicle would not need to use its AJ10 engine as it passed around the Moon in order to head back to Earth – gravity would do the work for the mission. However, the ESM’s propulsion systems would be required for various mid-course correction manoeuvres.

Captured through a window of the Orion capsule shortly after IPCS separation and with Integrity in a high Earth orbit (HEO), it images shows the night side of Earth, brightly illuminated by sunlight reflected by the Moon. The Sun is on the far side of Earth relative to Integrity, its light causing parts of the atmosphere to glow aurora-like. Credit: Reid Wiseman / NASA

The first of these course corrections was due on Flight Day 3. However, such was the accuracy of the SLS’s performance coupled with that of Integrity itself, this manoeuvre was discarded – the vehicle was precisely on the course it needed. On Flight Day 4 Hansen (a Canadian fighter pilot) and Koch (a jet-qualified civilian pilot) took the controls of Orion and put the vehicle through a further series of RCS tests, evaluating its ability to complete both 3- and 6-degrees of freedom of movement manoeuvres (that is, rolling, pitching and yawing around various axes without altering its general trajectory). Both Koch and Hansen reported the vehicle presented excellent and stable  handling.

Currently, the crew is due to pass around the Moon on Monday, April 6th. 2026 as they do so, they will reach a distance of approximately 406,773 kilometres from Earth, beating the previous record for the furthest humans have travelled from Earth to date – set by the abortive Apollo 13 mission in 1970 – by some 6,000 km. At this point, Integrity will be some 7,600 km beyond the surface of the Moon’s far side as it starts its journey home. The closest Artemis 2 will come to the surface of the Moon is approximately 6,513 km.

Taken on Saturday, April 4th, 2026 through a window on Integrity, this image captures the Moon’s nearside from a distance of around 180,000 km. Credit: NASA (astronaut response for image unnamed).

During the intervening period, the crew continue to test Integrity’s systems and capabilities and carry out a range of experiments, notably related to crew health and welfare. As a part of this work, Integrity carries two key experiments: AVATAR – A Virtual Astronaut Tissue Analogue Response, and an experiment system called ARCHeR (Artemis Research for Crew Health & Readiness (if there is one thing you definitely can say about NASA is that they work very hard at their acronyms!)

AVATAR can mimic individual astronaut organs, allowing medical experts evaluate tissue and other responses to various aspects of spaceflight and monitor essential biomarkers. AVATAR has been flown aboard the ISS several times, but this mission marks its first deep space mission – one that carries it and the Artemis 2 crew through the Van Allen radiation belts – thus offering the opportunity to gain further insight into the potential impact of these highly radioactive zones as Integrity zooms through them at several thousand km/h.

 ARCHeR (which I cannot help think was named by an NASA fan of Star Trek (see Jonathan Archer (Scott Bakula), first commander of the Star Ship Enterprise, NX01) uses movement and sleep monitors worn by the crew to gather real-time health and behavioural information for crew members so scientists can study sleep patterns and overall health performance.

Further, Artemis 2 is testing and demonstrating the Orion Artemis II Optical Communications System (O2O). This is an optical communications system uses laser beams for two-way communications between Earth and the mission. Smaller and lighter than a conventional radio system, O2O also uses less power and increases transmission rates (up to 200 Mbits per second). If successful, O2O could become a feature of future Artemis missions from Artemis 4 onwards and used in potential human missions to Mars.

I’ll have more on Artemis 2 next week. In the meantime, you can follow the mission in real-time, via NASA’s 24/7 livestream.

Space Sunday: four around the Moon and pausing Gateway

The Artemis 2 crew: (l to r): Commander Reid Wiseman; Pilot Victor glover; Mission Specialist Jeremy Hansen; Mission Specialist Christina Koch – but who are they? Find out below. Credit: NASA

If all goes according to plan, this coming week – possibly Wednesday, April 1st – we’ll see the Artemis 2 mission lift-off from Kennedy Space Centre, Florida, carrying four humans to the vicinity of the Moon, the first mission to do so in over half a century.

The journey to get to this point has been long and arduous; projects have been initiated, cancelled, re-organised and recommenced, funding has been provided, cut, renewed, reduced, extended… but the dream of returning to the Moon had remained steadfast in the eyes of enough people (doubtless aided by China’s emergence on the human spaceflight scene with their announced intent to go to the Moon), to keep political minds engaged in the journey.

Artemis 2 is very much a proving mission, aimed at ensuring the Orion Multi-Purpose Crew Vehicle and its European-built service module are both fit for purpose in supporting crews of four on extended missions to the Moon, as well as testing critical capabilities required for those missions which will actually deliver humans to the South Polar Region of the Moon starting with Artemis 4 – such as rendezvous and docking with the lander vehicle those headed for the Moon will use.

But who are the four people who will be aboard Artemis 2’s Orion capsule, with its “space toilet” that has so fixated much of the media? I thought I’d offer some brief biographical notes.

Commander Gregory Reid Wiseman, Mission Commander

NASA Astronaut and Artemis 2 Commander, Reid Wiseman. Credit: NASA

Known simply as Reid, and a US Naval aviator and Captain, Wiseman has already accumulated 165 days, 8 hours and 1 minute in space (including 12 hours and 47 minutes split across 2 EVAs), having flown to the International Space Station aboard Soyuz TMA-13M and as a part of the Expedition 40/41 crew between May and November 2014.

Born in Baltimore, Maryland in 1975, Reid earned a degree in computer science from  Rensselaer Polytechnic Institute, new York. In 2006, whilst a member of the Navy Reserve Officer Training Corps (NROTC), he gained a master’s degree in systems engineering from Johns Hopkins University.

In 1999, Wiseman was designated a Naval Aviator and underwent training to fly the famous F-14 Tomcat. Initially based at Naval Air Station Oceana, Virginia, he was deployed prior to being deployed to the Middle East for two tours of combat duty.  During his second tour of duty, he was selected to attend the US Navy Test Pilot School, where on graduation he was assigned as a test pilot and Projects Officer at the Naval Air Station Patuxent River, Maryland. Following this, he was assigned to carrier duty and transitioned to flying the F/A-18 super Hornet, once again seeing overseas deployments. He transferred to NASA in 2009.

Following his time aboard the ISS as a part of Expedition 40/41, Wiseman was appointed Chief of the Astronaut Office, a post he held for 2 years (December 2020 through the end of November 2022), stepping down from the post to active flight status in the hope of securing a position on one of the Artemis missions.  In April 2023, he was selected to command Artemis 2.

Wiseman was married to Carroll Wiseman (nee Taylor), with whom he had two daughters, through to her death from cancer at age 46.

Victor Jerome Glover Jr, Mission Pilot

Artemis 2 Pilot Victor Glover. Credit: NASA
Born in 1976 in Pomona, California, Victor Glover was a keen sportsman in his youth, playing for the California Jaguars football team as both a quarterback and running back and receiving the Athlete of the Year award in 1994. However, his father helped nurture a deep interest in science and engineering, leading him to earn a Bachelor of Science degree in general engineering in 1999 whilst attending the California Polytechnic State University, where he continued to play football as well as turning his hand to wrestling.

During the three years between 2007 and 2010, Glover earned three further degrees: a Master of Science in flight test engineering; a Master of Science in systems engineering and Master of Military Operational Art and Science, all of which were earned whilst he was a serving officer in the US Navy. He gained his aviator wings in 2001, and like Wiseman, trained on the F/A-18 Hornet. Also like Wiseman, he saw duty at NAS Oceana prior to being assigned to the USS John F. Kennedy and deployed to the Middle East as a part of Operation Iraqi Freedom.

Following this, Glover also entered the US Navy Test Pilot School, and served as a test pilot based at China Lake, California. Subsequent to this, he was sent to the US Naval Air Facility, Atsugi, Japan, and thence to the USS George Washington for a Pacific Ocean tour of duty.  Throughout his military career, Glover used the call sign “Ike”, a sobriquet jokingly given him by his first commanding officer, which was said to mean “I know everything”, on account of his long list of degrees.

As well as earning multiple technical degrees, Glover also obtained a Certificate of  Legislative Studies which led him being offered a role within Senator John McCain’s staff.

Glover joined NASA in 2013, and following the completion of his training, he was assigned to fly on the first operational flight (and second crewed flight overall) of SpaceX’s Crew Dragon, also serving as a crew member for Expedition 64/65. The mission launched in November 2020, with Glover clocking 167 days 6 hours and 19 minutes in space, 26 hours and 4 minutes of which were spent performing four separate EVAs.

He was announced as the Artemis 2 Pilot alongside Wiseman and the other crew members in April 2023. He is married to Dionna Odom Glover and they have four daughters.

Mission Specialist Christina Koch

Artemis 2 Mission Specialist Christina Koch. Credit: NASA

Christina Koch (pronounced “cook”, and nee Hammock) has accumulated the most time in space thus far of any of the Artemis 2 crew – a total of 328 days 13 hours and 58 minutes; 42 hours and 15 minutes of which were spread across 6 individual EVAs.

Born in Grand Rapids, Michigan in 1979, Koch was raised in Jacksonville, North Carolina. From the earliest she can remember she had always wanted to be an astronaut. Following schooling, she enrolled in the North Carolina State University, earning Bachelor of Science degrees in engineering and physics before going on to gain a Masters in electrical engineering. In 2001, whilst still studying, she was accepted into the NASA Academy Programme at the Goddard Space Flight Centre (GSFC), Maryland.

At GSFC, Koch worked out of the High Energy Astrophysics facility, contributing to scientific instruments on several NASA missions that studied astrophysics and cosmology. In 2004, Koch took a 3-year secondment with the US Antarctic Research Programme as a Research Associate, spending her time in both the Antarctic and Arctic regions. Whilst in Antarctica, Koch experienced temperatures of -79.4º C. She also served as a member of the fire fighting teams at the various bases she worked at, and also joined the Ocean / Glacier Search and Rescue teams.

Returning to the US in 2007, Koch contributed to instruments studying radiation particles for NASA missions, including the Juno and Van Allen Probes whilst seconded to the Applied Physics Laboratory at John Hopkins University. She then spent time at NASA’s sister organisation, the National Oceanic and Atmospheric Administration (NOAA).

In 2013, Koch was selected for astronaut training alongside Victor Glover. She was subsequently selected for Soyuz MS-12 as a part of the Expedition 59/60/61 crew. Koch joined astronaut Jessica Meir in the first all-female EVA ever undertaken, carrying out a series of upgrades to the power systems on the ISS across a total of three joint EVAs.

Originally, Koch was to have returned to Earth at the end of the Expedition 60 rotation. However, due to reassignment schedules, she was asked to remain aboard the ISS a further 6 months, allowing her to clock up her 328 days record in space – the longest continuous stay in space by a woman.

Jeremy Hansen (CSA), Mission Specialist

Artemis 2 Mission Specialise Jeremy Hansen. Credit: unknown

Jeremy Roger Hansen is the rookie among the crew and the only non-American. Born in London, Ontario, Hansen attended the Royal Military College, Ontario following his high school education. At RMC Ontario, he earned a Bachelor of Science degree with First Class Honours in space science in 1999, before going on to earn a Master of Science degree in physics  with a research focus on wide field of view satellite tracking.

In 2009, Hansen was accepted into the ranks of the Canadian Space Agency, training as an astronaut. In 2013 he was selected to join the European CAVES programme, becoming a “cavenaut”. The following year NASA selected Hansen to serve as an “aquanaut” aboard the Aquarius underwater laboratory during the 7-day NEEMO 19 undersea exploration mission.

Hansen is married to Doctor Catherine Hansen, a distinguished expert in women’s health. Together, they have three children.

The Artemis 2 Mission Patch

The Artemis 2 mission patch

All NASA missions traditionally have a mission patch designed by the crew (with NASA management approval over the final design!).

These patches are generally symbolic in nature, often containing references to the mission or to current or past space events. In this, the Artemis 2 mission patch is no exception.

Firstly, its shape is symbolic of the Orion capsule’s general shape, indicating the vehicle as a home for the 4 crew. A stylised “AII” occupies the right side of the patch, signifying the mission umber and the fact that Artemis 2 is for “all humanity – a play on “for all mankind” of the Apollo era. This sits directly over the lunar far side – thus denoting the mission’s trip around the Moon, a red ribbon running from Earth and around the Moon mirrors a similar ribbon in the Project Artemis patch, the red of the ribbon indirectly referencing NASA’s role in aeronautics – as per the red chevron in the NASA insignia). The Moon is dominant in the patch, with the Earth rising behind it.

If this particular part of the patch rings bells, rest assured it is intentional: the Moon with the Earth rising behind it is designed to evoke memories of the famous Apollo 8 image Earthrise, thus linking Artemis II with the first Apollo space mission to fly around the Moon and back to Earth.

How to Watch the Launch

Artemis 2 is due to launch no earlier than 22:24 UTC on April 1st, 2026. You can watch the countdown and launch via NASA’s livestream (commencing 17:50 UTC on April 1st).

Lunar Gateway ”Paused”

Jared Isaacman, NASA’s current Administrator, continues to shake things up around Project Artemis – and quite possibly for the better in terms of focus and goals.

As I’ve previously covered, Isaacman has already made significant changes to Project Artemis which impact both missions and hardware (e.g. Artemis 3 will now be an Earth-orbiting mission, not a lunar landing mission).

Gateway Station: a necessary adjunct to lunar research and surface operations or a funding boondoggle? Jared Isaacman appears to lean towards the latter, “pausing” the Gateway programme in favour of more direct lunar operations.

On March 24th, 2026, Isaacman informed NASA personnel and the press that the space agency will be “pausing” work on its proposed Gateway Station, the much heralded space station occupying an extended halo orbit around the Moon. For those (myself included) who could not see any practical benefits in spending time and money developing yet another (if much smaller than the ISS) space station in lunar orbit, this is welcome news.

Gateway station has always come across as an unnecessary complication in getting people to / from the Moon. It’s halo orbit means it will only be within reach of crews on the lunar surface once every seven days – which is great when you have an emergency and need to evac someone pronto and then have to rendezvous with the station in order to get them back to Earth. It will also require a lot of additional faffing around with rendezvous and docking manoeuvres and generally act as something of a boondoggle, drawing on funding that could be better spent elsewhere – such as the infrastructure actually required to establish a permanent base on the Moon.

NASA Administrator Jared Isaacman continues to shift NASA’s course towards the Moon – for the better. Credit: NASA

This is what Isaacman is proposing: spending some US $20 billion over a period of seven years – a good portion of that money coming from allocations that would otherwise have gone to gateway – to develop and construct a permanent base on the Moon. Isaacman also expects member states involved in the Artemis Accords to help cover a portion of the of the costs – although as I’ll come to, this might not be so easy.

No hard details on the base were given – such as location, what infrastructure will be required (such as power systems – presumably nuclear – and so on), or how delivering the infrastructure and materials required to build the base will be achieved – although presumably Isaacman will be looking to the likes of Blue Origin and SpaceX with cargo variants of the lunar landing systems.

Not everyone is happy with the move, however. Japan and the European Space Agency were already partners in Gateway and due to provide core components and elements for the station and have been gradually ramping-up for production of said elements. Neither appear to be entirely sanguine over Isaacman’s decision, with ESA issuing a terse statement that could be read as meaning they’d been giving little or no warning of Isaacman’s decision, re Gateway.

The European Space Agency is currently holding close consultations with its member states, international partners and European industry to assess the implications of this announcement.

– ESA quote via AFP in response to Isaacman’s announcement on “pausing” Gateway Station

If this is the case – that there was no in-depth consultation on Gateway’s future with the likes of ESA and JAXA, then  while the “pausing” of Gateway is welcome, the handling of the announcement could be seen as somewhat less than diplomatic.

Space Sunday: more Moon bits

The Artemis 2 SLS and Orion MPCV depart the Vehicle Assembly Bulding at Kennedy Space Centre on March 20th (UTC), heading back out to the pad for a potential launch on April 1st, 2026. Credit: Terry Renna / Associated Press

The Space Launch System (SLS) which will launch a crew of four on a trip around the Moon aboard their Orion Multi-Purpose Crew Vehicle (MPCV) during the Artemis 2 mission, has returned to the launch pad at Kennedy Space Centre’s Launch complex 39B (LC-39B).

The rocket had to be returned to the Vehicle Assembly Building on February 25th, 2026 after a helium pressurisation issue was found in the rocket’s upper Interim Cryogenic Propulsion Stage (ICPS), resulting in a helium leak.  While the leak could be resolved with the vehicle on the pad, the need to ensure the ICPS has a stable helium pressure flow when in operation called for a rollback to the VAB to allow engineers unfettered access to the upper stage in order to resolve the problem.

The second roll-out to the pad mirrored the preparations for the Artemis 1 uncrewed mission in late 2022, which also saw the SLS rocket used on that flight rolled out to the pad, encounter issues (with the main propellant feed mechanism intended to fill the rocket’s tanks with liquid hydrogen and liquid oxygen) then rolled back to the VAB, before a second roll-out to the launch vehicle back to the pad. Given the overall success of Artemis 1 (despite leading to concerns over the Orion capsule’s heat shield), the roll-out, rollback, roll-back of Artemis 2 might be seen as a good (if delaying) omen.

A close-up of the Orion MPCV encased within its Launch Abort System (LAS) shroud, the LAS motor visible on the tower above it, and the European service Module (ESM) directly below the capsule’s “dome” protected by its pair of white payload fairings. Credit: Terry Renna / Associated Press

The second roll-out took place overnight on March 20th, 2026 UTC (March 19th – 20th, US EDT) with the rocket and its Mobile Launch Platform (MLP) inching away from the confines of the VAB atop one of NASA’s mighty Crawler-Transporters. The 6.4 kilometre journey to the pad took almost 12 hours to complete, with the SLS and MLP positioned on the pad at around 15:20 UTC on March 20th.

The next launch window for the mission opens on April 1st, 2026 and runs through the first few days of April. NASA is currently targeting the very opening of the launch window on April 1st for a launch attempt, giving them maximum leeway should any minor issues occur or the weather decides to play a hand in matters.

An infographic produced by L3Harris, an Artemis contractor, highlighting features of the Artemis 2 mission, including the on-orbit rendezvous and docking simulations the crew will perform using the SLS ICPS as a dummy target, and the fact the flight will be a last hurrah for NASA’s most reliable Space Shuttle Main Engine, having flown 15 previous times. Credit: L3Harris

Once launched, Artemis 2 will initially enter a 24-hour orbit around Earth. During this time several critical systems not carried aboard Artemis 1 will be tested and checked. Additionally the ICPS will be used to lift Orion into an elliptical orbit with a high apogee whilst imparting the craft with much of the velocity it will need to head for the Moon.

The ICPS will then separate from Orion and its European Service Module (ESM) and become a passive dummy target for the crew on Orion to carryout mock rendezvous and docking manoeuvres of the kind Orion will have to perform when operating around the Moon in future missions in order to dock with the lunar landing vehicles and (later) Gateway station.

Once these tests have been completed, Orion will use the ESM’s min motor to push it into a free return trajectory around the Moon on a trip lasting 9-10 days, affording the crew time to thoroughly check-out Orion’s systems and amenities.

EUS Replacement  – I Called It

On February 27th, 2026, NASA provided an update on the entire Project Artemis, noting some significant changes to mission and vehicles (see Space Sunday: major Artemis updates and a rollback).

One of these changes was the cancellation of the planned Exploration Upper Stage (EUS) the more powerful upper stage for the SLS that has been under development at Boeing for several years, and would replace the ICPS on mission from around Artemis 5 (now Artemis 6).

ULA”s Interim Cryogenic Propulsion Stage (ICPS) for the SLS rocket, now set to be replaced in the future by ULA’s Centaur V. Credit: ULA

At the time of the announcement no indication was given as to what would be used to replace the EUS and ICPS, or whether NASA was looking at something to match the ICPS or EUS in capabilities. However, in my article linked to above, I noted that as far as I could see, there were only two possible contenders: Blue Origin, with their New Glenn upper stage, or United Launch Alliance (ULA) with their Vulcan-Centaur V upper stage, part of a family of Centaur upper stages that has gained a long and venerable operational history.

On March 10th, 2026 NASA confirmed my thinking by making a procurement filing to replace the ICPS and EUS with ULA’s Vulcan-Centaur V. Whilst some modifications to the stage will be required, the V-C 5 was selected by NASA in part because of its pedigree stretching back over 60 years (which was seen as overcoming the fact the Centaur V has itself only flown twice), and in part because it is almost a simple drop-in replacement for EUS and (particularly) ICPS.

The first Centaur V (officially designated the Vulcan-Centaur V) to roll off of ULA’s production line, and used in ULA’s first Vulcan-Centaur rocket launch. Credit: Tony Burno (former CEO of ULA)

Once upgraded, the V-C 5 will offer more-or-less the same capabilities as ICPS, but not as great as the EUS. However, the lineage of Centaur means NASA has an assured route to have the system upgraded to meet future needs, if required.

The NASA announcement also indicated that, per my theorising, they had also considered the Blue Origin New Glenn upper stage. This was only ruled out on the basis it has only flown twice thus far – albeit completely successfully on both occasions – and NASA wanted an upper stage replacement will a decent launch / success / failure history and a track record of development they could properly evaluate.

ULA’s established infrastructure, resources, flight history, existing cross-program integration, and human-rating familiarity with the Centaur upper stage represents the only currently viable opportunity for the Government to accomplish Artemis mission objectives and requirements while also maintaining the agency’s programmatic goals.

– From the NASA procurement filing

So, yay me for calling it.

Artemis Accord Signatories Mull How to Deal with Emergencies and More

When a single nation goes to the Moon, there’s a pretty narrow field of operational requirements that need to be dealt with to keep people safe, avoid misunderstandings, demote working areas, and in handling thing like emergency situations.

When multiple nations decide to not only head for the Moon, but head for the same part of the Moon – in this case the South Polar Region – such requirements get a lot more complicated.

Currently, there are two confirmed groups of nations participating in projects aimed towards a long-term human presence within the Moon’s SPR – those of the US-led Artemis Accords (numbering, at the time of writing, 61 nations – not all of whom will be seeking to send their own astronauts to the Moon) and the China and (nominally) Russian-led International Lunar Research Station (ILRS), comprising (at the time of writing) 13 nations.

As such, serious considerations need to be given to managing diverse (or even competitive) lunar operations, denoting separate research and work environments, establishing buffer zone between different interests and working areas, and – critically – how to handle emergencies and provide emergency support.

The latter is something very much up in the air – although one would hope any emergency call for assistance would be responded to without regard to the nationality or allegiance of those making the call. For the former – the establishment of buffer zones is seen by members of the Artemis Accords as the way to go, although they prefer the term “safety zones”.

These would, in theory, allow signatory states pursue their own specific research interests on the Moon without the risk unintentional (or even intentional) interference from other member states. The problem is, how should a “safety zone” be defined? Should limits be placed on the size of such zones? How should they be recognised? How lawful would they be? How can they be enforced when it comes to non-Artemis nations?

A major concern here is that of territorialism: member states (or even the Artemis project as a whole) laying claim to a large area of the Moon, or even an entire region. Such claims are explicitly outlawed under the 1967 Space Treaty, but if sufficient resources of a valuable nature are found in a particular area of the Moon, is that treaty enough to stop a nation establishing a presence there and declaring an exclusionary “safe zone” around it before hoisting their flag and treating it as a national enclave? And what sort of response should that garner if it did happen?

We’re a long way away from where these issues might start to become problems, but they do need to be addressed in some form – and not just by members of the Artemis Accords – but by all nations, whether or not they are signatories to the Accords or the ILRS.

Lunar Ice Might be Rarer than Thought

One of the reasons for the interest in sending humans to the lunar South Polar Region has been the fact that the region is heavily cratered, and due to their position, many of the bottoms of these craters never see daylight or feel the Sun’s heat. Referred to as permanently shadowed regions (PSRs) it has been theorised that these craters could be home to large, accessible (or at least semi-accessible) deposits of the Moon’s water ice – which would be enormously beneficial to human operations on the Moon if they could be exploited.

This idea is backed-up by PSRs elsewhere in the solar system being home o water ice, including the planet mercury and the asteroid Ceres, to name two examples. However, despite all our orbital observations of the Moon, confirming the presence of water ice in lunar PSRs has been difficult; not least because of the orbital complexities involved in get a satellite to overfly them and the fact they are very deeply shadowed when seen form orbit.

To try to understand just how much ice might be present in the bottoms of permanently shadowed craters on the Moon, a team of US researchers operating out of the University of Hawaii at Manoa developed ShadowCam, an imaging system 200 times more light-sensitive than most other cameras used to study and map the Moon from orbit.

ShadowCam forms a part of the payload flown aboard the Korea Pathfinder Lunar Orbiter Danuri, South Korea’s first lunar mission, which entered orbit around the Moon in December 2022. Classified as a NASA experiment, ShadowCam first flexed its muscles in mid-2023, demonstrating it raw ability to see in to PSRs and reveal never-before-seen details.

A computer rendering of the 678 kg Danuri (Korea Pathfinder Lunar Orbiter), which hosts the ShadowCam imaging system. Credit: South Korea Ministry of Science and ICT

More recently, ShadowCam has been engaged in a campaign to image multiple PSRs in the Moon’s Polar Regions (north and south) to reveal more of their secrets. And while the campaign has been very successful in providing new data and information on the observed craters, the one thing it hasn’t found is any sign of water ice deposits.

To be clear, any water ice contained within lunar craters is not going to be pure. It’s going to be mixed with and even covered by a layer of lunar regolith (the loose dust and rock fragments making up the surface material of the Moon). As such, these mixtures would produce different levels of reflectance and light scattering depending on the regolith-to-ice ratios encountered, although astronomers work on the basis that a mixture that is around 20-30% water ice would be enough to be detected by a sensitive-enough imaging system – and as noted, ShadowCam is very sensitive.

A selection of ShadowCam images of lunar North Pole and south Pole PSRs, with features and details the system has revealed for the first time – although none of them show any indication of water ice within the craters. Credit: Nasa / University of Hawaii

However, none of the dozens of PSRs on the Moon imaged by the instrument showed any signature that might indicate water ice was present in some degree. This doesn’t necessarily mean the water ice is not there; it could exist in percentages as low as 10%, or even in single digits – as these are levels too small for ShadowCam to currently detect, although the University of Hawaii team hope to be able to use software updates in their processing software that would reveal water ice in concentrations as low as 1%.

But that said, the real rub here is that even if such low percentages of water ice are revealed, and assuming ShadowCam’s results hold as more lunar PSRs are examined, then it is obvious that the hoped-for abundance of water ice to assist in lunar operations simply don’t exist or might be so small as to not be worth the expense and effort in trying to exploit them. As such, the water needed to help sustain human operations on the Moon and to enable various construction and technology options is going to become a further payload mass that will have to be routinely shipped from Earth.

Space Sunday: of China’s goals and radiation belts

A artist’s impression of the first Chinese crewed mission to the surface of the Moon, taking some liberties with the appearance of the Lanyue lunar lander and the position of the Earth relative to the horizon. Credit: Getty Images

I’ve covered China’s space programme in some detail in these pages, not so much because I’m a fan of the Chinese government, but because – and US readers may not like it – China has proven it can put together a highly competent and integrated national space programme. One that is, and despite all of its magnificent achievements to date over the decades, is far more integrated in terms of projects and goals than the US national space programme, which has, where manned space exploration is concerned, largely plodded along somewhat aimlessly for some 40 years.

Obviously, a lot of this comes down to politics and governance. The US government is answerable to the people, and this includes NASA which is – completely and utterly wrongly – seen by many as a high-cost waste of taxpayer money. I say “wrongly” deliberately, as NASA’s budget accounts for just 0.35% of the US federal budget. Compare that to the 62% gobbled up annually by the Pentagon.

Of course, there are considerable differences in scale and need between the Pentagon and NASA, but considering all the latter does achieve annually in the fields of space science, astronomy, space exploration health and safety, avionics and aeronautics even without firmer integration of its major goals and ambitions, adds up to NASA doing a huge amount for very little in the overall scheme of things.

China’s government does not answer to its people, ergo, its spending is entirely at its own whim. This means China can be more indulgent in its spending around space goals (something also helped by the fact that a good portion of the Chinese space programme is linked to the People’s Liberation Army, which can swallow costs and overruns in what might otherwise be seen as civilian operations in the name of “national security”).

Even so, since the 1970s, China has sought to pace its activities in space in a manner that is both pragmatic and which has enabled them to build expertise in planetary science, rocketry, launch capabilities and to develop a coordinated approach to space exploration. The latter, as I recently covered in these pages, is particularly notable within China’s lunar ambitions, which have throughout seen both robot missions (their family of Chang’e landers, orbiters and rovers) and upcoming human missions tied together in one over-arching programme – the Chinese Lunar Exploration Programme, or CLEP. True, NASA did something similar with Project Apollo and is doing so again with Project Artemis, but the degree of shared goals and progression from robotic to human exploration is not on the same scale as China’s.

China’s Tiangong space station not only operates as a Earth-orbiting research station, it has a number of roles to play in China’s lunar ambitions. Credit: CMSA

The same is true when it comes to China’s Tiangong space station and CLEP. This operates both as an independent orbital research facility and as an Earth-bound extension to CLEP, providing an on-orbit medical research facility, a training environment to help lunar crews carry out tasks in microgravity as they might whilst going to or returning from the Moon, and providing the means to develop food cultivation methods which could be employed on the Moon to help supplement diets.

As a part of this work, 2026 will see the launch of Shenzhou 23 in April. The 17th Chinese crewed spaceflight and the 23rd for the Shenzhou programme overall, the mission carry three tiakonauts to Tiangong, as is usual for such missions. However, unlike all crewed missions to date, which have seen personnel spend no longer than 6 months on the station, Shenzhou 23 will see one of the crew (as yet unnamed) spend a full year in orbit.

Such long duration missions are the stuff of legend for NASA and Roscosmos, with astronauts and cosmonauts alike spending in excess of a year in space, largely for medical research purposes (such as studying the impact of microgravity on the human physiology) and kind-of tangentially focused on some ideas of human deep space missions, such as the now defunct near-Earth asteroid rendezvous mission or looking towards some far-off mission to Mars.

For China, the goals are both similar and more immediate: the Chinese want to know more about the physical and psychological impact of a long-duration stay in near zero gravity and how the more debilitating effects might be countered and they want to start gathering data on the effects of something like a voyage to Mars undertaken in microgravity – a human mission to Mars also being one of their stated medium-term goals once they have established a presence on the Moon.

Also coming up this year is the first – and uncrewed – orbital flight test of China’s Mengzhou multi-purpose crewed space vehicle. Set to initially operate alongside Shenzhou (itself a derivative of Russia’s Soyuz vehicle), Mengzhou is set to be – as I’ve also mentioned previously – an integrated and highly-capable vehicle, designed to both provide three crew (as standard, although it can carry up to 6 or 7) with access to Tiangong, and also in an extended operations mode providing 3-4 taikonauts with a ride to lunar orbit.

China’s workhorse Shenzhou (left), comprising a forward cargo module with integrated airlock, a central crew module capable of supporting up to three tiakonauts and large service module, is due to be joined by the more up-to-date Mengzhou vehicle, capable of carrying crews of up to 6 or 7 in the forward (top) capsule unit, which can also include cargo racks, and a service module for power and propulsion. Credit: various

No target date for this orbital flight test has yet been given, but all major milestones required for it to take place have been successfully cleared, and its dedicated launch vehicle, the Long March 10 (CZ-10) is also very close to being ready for an orbital launch attempt, having passed the majority of its development and testing milestones.

Nor does it end there in terms of ambitions and integration. Like NASA and Roscosmos, China is working to encourage international cooperation and participation in its space aspirations.  CLEP is set to evolve into the International Lunar Research Station (ILRS) project which will see participation in China’s lunar project from Russia, South Africa, Belarus, Azerbaijan, Venezuela, Pakistan and Egypt, to name the headline nations.

Whilst not as all encompassing as the Artemis Accords (which involve 61 countries at the time of writing), ILRS nevertheless points to the fact that China is determined to be a major leader in space-based human activities. To this end, Shenzhou 24, scheduled for later in 2026, will see a Pakistani astronaut fly to Tiangong, and there are plans to fly astronauts from both Macau and Hong Kong to the station as well (although these are more from Chinese-managed Special Administrative Regions rather than representatives from genuine foreign nations).

China’s First lunar Mission May Target Rimae Bode

Whilst the Chinese Lunar Exploration Programme is, like Project Artemis, focused on the South Polar Region of the Moon for the establishment of a lunar research station, the first crewed lunar landing on the Moon by Chinese nationals will not be in that region; instead, it will likely be to the lunar nearside, not too far from the equator.

Currently, the possible prime candidate for China’s first crewed mission to the Moon is Rimae Bode  (crater Bode) located to the left of Mare Vaporum (seen towards the right of the image above), within semi-chaotic and volcanic terrain. Credit:  Selenochromatics

There are several good reasons for this. Most notably, such a location would enjoy direct line-of-sight communications with Earth throughout the majority of the mission. Secondly, it can be timed to take place under more favourable lighting conditions than might be the case with a mission to the South Polar Region. Thirdly, it doesn’t require a lot of complex orbital manoeuvring in order to get the lander into the desired obit, again simplifying the overall mission profile. There’s also the fact that China has never been to the Moon before with a human crew, thus a nearside mission with full communications, etc., allows mission managers to gain vital experience in managing such a mission without the complications a polar landing might bring.

The potential landing zone for this – as yet unnamed mission, which is targeting 2030 – is Rimae Bode. Located at the boundary between Mare Vaporum and the highlands on the central lunar nearside, the area has been selected as the likely landing site because of its scientific value. Diversely volcanic, the region provides easy access to assorted  lunar material and differing terrain types within a relatively small area – ancient lava flows, rilles (long, narrow, channel-like features formed by ancient lava flows) and local impact craters which have left subsurface materials exposed on the surface for easy collection and study.

The Rimae Bode region (Bode also being the name of a local crater) is rich in “young” impact craters which may reveal secrets as to the Moon’s interior. Credit: NASA

Rimae Bode is actually one of 106 potential landing candidates under consideration for the first Chinese crewed landing on the Moon, but it has grown in popularity with scientists and mission planners because of its sheer diversity and opportunities for exploration. further, it has long been considered a site worthy of human and / or robotic exploration and because it is relatively accessible.

Of particular interest to scientists is the potential for Rimae Bode to reveal insights into the Moon’s deep interior.

The most ground-breaking discovery from the Rimae Bode region would likely come from the dark mantle deposits, which consist of volcanic ash and glass beads that were violently erupted from the moon’s deep interior billions of years ago. These samples act as ‘messengers’ from the lunar mantle, offering a rare opportunity to directly analyse the chemical composition of the moon’s deep heart — information that is usually hidden beneath miles of crust.

– Professor Jun Huang, China University of Geosciences, Wuhan

Examining this material together with studying the region’s complex network of lava channels, could help in the reconstruction of the Moon’s early volcanic history, with samples perhaps indicating how the Moon cooled and what triggered its most massive eruptions. Studies of the region and its rocks and minerals might even inform scientists on how all rocky planets, including Earth, cooled and evolved after their birth.

The final decision on a landing zone for the first Chinese crewed mission to the Moon has yet to be made, so Rimae Bode may yet lose out. However, given the nature of the region, its location and the fact it has long been the focus of scientific curiosity possibly makes this unlikely.

Van Allen Probe Makes Belated Return to Earth

Wednesday, March 11th, 2026 saw the return to Earth of one of two probes launched in 2012 to increase our understanding of the Van Allen radiation belts around our planet.

Named for James Van Allen, who discovered them in 1958 using data gathered by America’s first successful satellite, Explorer 1, the Van Allen belts are missive, if invisible doughnut like structures surrounding Earth in two layers – the inner and outer radiation belts. Combined, they range in altitude from a few hundred kilometres to some 96,000 km, and comprise protons and electrons trapped within the Earth’s magnetic field.

A simplified cross-section of the Van Allen radiation belts. Credit: Booyabazooka

The Van Allen belts are what might be called frienemies of life. On the one side, they act as a shield, deflecting harmful cosmic radiation and the relentless stream of charged particles blasted out by the Sun, making our planet far more supportive of life than would otherwise be the case. On the other, they’d happily kill you if you loiter in them for too long. They are also a constant hazard to satellites orbiting through them, as they will also merrily fry unprotected electronics and, during periods of high solar activity, they “puff up” with even greater concentrations of radiation which can easily kill satellites completely and disrupt Earth-based communications, GPS systems, and so on.

Spaceflight and Moon landing deniers point to the Van Allen Belts as “proof” that all space missions are “fake” as “no-one can survive them” – although their reasoning is far more a demonstration of their inability to grasp concepts such as velocity together with an overly simplistic view of what the belts are and what is required form them to have a lasting impact. However, they are correct in their stance that loitering within the influence of the belts is definitely not a good idea.

The two Van Allen Belt probes double stacked in one half of the payload fairing of their Atlas V 401 launch vehicle, ahead of their 2012 launch. Credit: Kim Shiflett

The twin Van Allen Probes were specifically built and launched to increase our understanding of the Van Allen Belts in terms of their ability to severely harm the inner electronics and workings of satellites that have no other choice but to loiter within the radiation environment as they orbit the Earth. Armed with hyper-sensitive sensors and recorders, the two probes of an identical design were given an initial 2-year primary mission. However, both continued to operate through until 2019, when their stocks of manoeuvring propellants were exhausted, leaving them unable to main a proper communications / power generation orientation, and both were retired. In that time, the craft – called simply “Probe A” and “Probe B” gathered a huge amount of data concerning the belts and the dynamics at work within them; data which has both altered our understanding of the belts and which is still being researched and studied.

Given their extreme orbital regime (617 km to over 30,000 km), both Probe A and Probe B were expected to remain in orbit until the mid-2030s. However, such has been the level of solar activity from 2019 onwards (with Solar Maximum being reached in 2024), the upper reaches of our atmosphere have been greatly inflated as a result of solar radiation influx. This has increased drag on multiple satellites, including the 600 kg Van Allen probes, with Probe A in particular being impacted.

By 2025 it was clear that Probe A was coming down sooner rather than later, the atmospheric drag having significantly lowered its altitude overall, with its perigee in the low hundreds of kilometres. By early 2026, it became obvious the probe only had weeks or months at the most left before it reached interface with the denser atmosphere and started to break / burn up. This started on March 11th (UTC) as it entered the denser atmosphere over the Galapagos Islands. The majority of the probe was destroyed in the upper atmosphere as it passed over South America, although some debris is believed to have fallen into the Atlantic Ocean.

Whilst also affected by the Sun’s activity, Probe B currently remains in orbit, although it is expected to now re-enter the atmosphere in 2030, rather than the mid-2030s as originally anticipated.

Space Sunday: of Vera C. Rubin, pollution and a question of life

The Vera C. Rubin Observatory is a facility I’ve covered numerous times in Space Sunday as it has been constructed and outfitted. Perched atop Cerro Pachón in Chile, at an altitude of 2.67 kilometres, the Vera C. Rubin promises – with a caveat – to totally alter the way we see the cosmos around us.

This is because the telescope is to carry out a 10-year survey to probe the deepest reaches of our universe to reveal its secrets. Called the Legacy Survey of Space and Time, or LSST (“legacy” here referring to the fact that the observations and images the telescope makes will be of interstellar objects as they appeared hundreds of thousands through hundreds of millions of years ago), the survey will be the most comprehensive of its kind to date, and involve astronomers from around the world.

The secret weapon the observatory uses in this survey is the largest telescope-camera system ever built. The primary lens of this behemoth is 8 metres across, with the entire camera weighing some 3 tonnes. Its construction took a decade, after which it had to be carefully packaged and shipped to Chile and up to the observatory, where it was installed into the facility as the core part of the Simonyi Survey Telescope (named for the private donors who sponsored the telescope, Charles and Lisa Simonyi).

A rendering of Vera C. Rubin’s Simonyi Survey Telescope with the camera system and lenes at its centre. Credit: Rubin Observatory project office.

Overall, the telescope is a 6.5m class optical telescope, with a 3.2 gigapixel charge coupled device (CCD) for imaging. Over the course of the LSST, the observatory is expected to reveal and catalogue a wide range of objects, including some 5 million Sun-orbiting asteroids (including around 100,000 near-Earth asteroids at least 300 metres across, some of which might present the risk of colliding with our planet at some point in the future); imaging around 20 billion galaxies, 17 billion stars and up to 6 million planetary systems orbiting other stars.

In addition, it is hoped the observatory will be able to catalogue “primitive” objects in the Kuiper belt (i.e. those thought to have existed at the time of the birth of our Sun), observe thousands of novae and supernovae to help astronomers to further understand the nature of the galaxy

The telescope had is “first light” – the first practical use of a telescope after it has been constructed, calibrated and commissioned – took place in June 2025. These took the form of “teaser” images as to what the telescope would be capable of, featuring the  Trifid and Lagoon nebulae and extracts from a wide-field view of galaxies in the Virgo Cluster.

More recently, the images of the Virgo Cluster have been further cleaned-up and re-annotated, revealing the sheer power and depth of observations Vera C. Rubin can make. The image below covers a 3.5 degree diameter field-of view and reveals over 100 galaxies and numerous stars (particularly those within the constellation of Virgo) within our own galaxy, presenting a stunning insight into just how vast our universe is.

An annotated version of the Vrgo Cluster showing some of the 10 million galaxies captured in the observatory’s first light images. (Image credit: RubinObs/NOIRLab/SLAC/NSF/DOE/AURA) – click for full size & then zoom for detail

The telescope is designed to take multiple pictures during each observation period, the main camera taking a 30-decond exposure for each image, with an active optics system with wavefront sensors within the telescope keeping the mirrors precisely configured, aligned and focus for the clearest possible images.

However, whilst images from the telescope are stunning an informative, they also come with a problem, albeit not one of the observatory’s own making. That problem is satellite pollution. In short, megaconstellations like SpaceX Starlink and China’s Guowang are lobbing thousands of low-Earth orbiting satellites into the space around us. These satellites inevitably reflect the Sun’s light as they travel across the sky, and in time-lapse images, this reflected light appears as narrow streaks across an image – and not just one or two, but potentially dozens at a time. All of which has to be painstakingly cleaned-up in order for the full value of images to be obtained.

The issue here is that removing satellite steaks is not just a case of pulling up Photoshop and then editing – the very act of trying to clean up images to remove the streaks can introduce its own errors which might prove impossible to account for and which risk misinterpretations of what is being seen being made.

A time-lapse image of Comet C/2023 A3 (Tsuchinshan–ATLAS) taken from Italy on August 1st, 2024, demonstrating the issue of satellite pollution – the lines crossing the image are caused by the passage of satellites (predominantly Starlink) Credit: Rolando Ligustri)

Nor do the problems end there. A relatively new company, Reflect Orbital has grand designs of orbiting a 50,000-strong megaconstellation of satellites which can deploy large Sun-reflecting mirrors. The aim? To provide “responsive lighting after dark and to increase the effective hours of solar energy production”.

Currently, the company plans to launch a proof-of concept satellite called Eärendil-1 (which likely has Tolkien spinning in his grave) capable of deploying and 18m by 18m Mylar mirror utilising the same material as used to reflect sunlight off of space vehicles, sometime in 2026. This project has drawn such condemnation from astronomers and others (additional concerns about directing sunlight onto specific parts of the Earth and turning “night into day” are that it could have a serious negative impact on the circadian cycles of animals and humans), that Reflect Orbital has promised to work to minimise the broader impact of their idea. Time will tell on whether this offer is genuine or not.

Both the International Astronautical Union (IAU) and the US National Science Foundation have called on companies launching satellite constellations to be more aware of their negative impact and to reduce the reflectivity of their satellites – the IAU recommending that all satellites should appear no brighter than magnitude 7 objects.

Multiple companies have agrees to try to reach this goal, but thus far few have shown any real movements towards it. SpaceX, for example, gave assurances that it would work to reduce the reflectivity of its version 2 Starlink satellites compared to its version 1.x units. However, whilst effects were made, they fell far short of the level requested by the IAU, and efforts to further reduce reflectivity appear to have ceased. Others, such as  Texas-based AST SpaceMobile raised a middle finger to the IAU’s recommendation by launching its Bluewalker 3 satellite with a reflectivity some 400 times greater than magnitude 7. Currently, that company plans to launch some 60 even larger and more reflective Bluebird Block 2 satellites into LEO during 2026/27.

The Vera C. Rubin Observatory imaged in 2022 during the final construction phase, seen against the backdrop of the Milky Way galaxy. time-lapse views of the night sky like this – and those captured by observatories like the Vera C. Rubin, are under increasing threat from low earth orbiting satellite clusters like Starlink and  Guowang. Credit: Rubin Observatory/NSF/AURA/B. Quint

What is evident from this is that formalised regulation is required to try to minimise the impact the over-use of the low-to-medium Earth orbit regime, lest our ability to learn about our planet, solar system and the cosmos around us be otherwise degraded to an unconscionable level.

“Life Here Began Out There”

Battlestar Galactica fans will likely recognised this quote, being some of the opening words of the original series (as spoken by Patrick “John Steed” Macnee!), and a refrain which popped up in Ronald D. Moore’s largely excellent reimagining of the Galactica tale. It’s also a phrase which has taken on a certain nuance in recent times.

ALH84001 on display at the Smithsonian Museum of Natural History, Washington DC

It has long been known that – particularly in the very early history of the solar system – asteroid and other impacts on Mars could carry enough force to send chunks of Martian rock clean off the planet and into space, with some of them eventually coming under the influence of Earth’s gravity and falling down on our planet. One of the most famous pieces of evidence for this is the notorious Allen Hills fragment ALH84001. This was a fragment of rock shown to be consistent with the rocks of Mars discovered in the Allen Hills region of Antarctica in 1984,and which went on to cause a stir when it was announced the rock apparently contained evidence of fossilised Martian life (spoiler alert: it likely didn’t).

ALH84001 is not the sole example – Antarctica is actually a popular (but not the singular) place for asteroid fragment hunting, as the charred and discoloured can often be found close to the surface of the ice and snow fields, where they send out starkly to the human eye. Multiple expeditions have found lumps of asteroid and rocks which have later proven to have arrived here from the Moon or Mars.

Whilst the investigations around ALH84001 may have been flawed, they did help kick-start a debate as to whether life here on Earth might have originated elsewhere – such as on Mars – or might have been kick-started not by Earthly processes alone, but with the assistance of organics-bearing asteroid fragments plummeting through our atmosphere to arrive here.  The idea even as a name: lithopanspermia.

Now, a new study suggests that, if not the actual case, either scenario is actually possible. Published in the journal PNAS Nexus, the study demonstrates how bacterium can survive the massive forces of an asteroid impact blasting the rock containing them into space, the extremes of interplanetary space and their fiery arrival on another world possibly altered, but otherwise largely unharmed.

In particular, the study shows that Deinococcus radiodurans, a particularly hardy bacterium known for its thick outer shell and an ability to repair its own DNA, as well as being tolerance of the kinds of radiation it might be exposed to in interplanetary space, could indeed survive all the trials and tribulations of being blown off of somewhere like Mars and landing here on Earth. In fact, so hardy is D. radiodurans that it has for some time had the nickname, “Conan the Bacterium”.

Most intriguingly, the bacterium has been found within rocks in the highlands of Chile and other regions were asteroid fragment hunting is popular.

To simulate the forces involved in an asteroid impact, the researchers sandwiched samples of D. radiodurans between two steel plates. Using a gas-powered gun, they fired a projectile at roughly480 km/h), subjecting the microbes to pressures between 1 and 3 gigapascals. That’s around 10 times greater than the maximum pressure which can be experienced here on Earth (and at the bottom of the Mariana Trench): 0.1 gigapascals.

At the low-to-mid-ranges of impact (1 to 2.4 gigapascals), D. radiodurans showed either no sign of damage or varying degrees of cell rupturing. At the higher pressure, damage was more extensive, but in both the mid-to-high level ranges, the team behind the study witnessed the bacterium’s self-repair mechanisms go into action, repairing damaged DNA and renewing damaged cell membranes.

Researchers exposed the bacterium Deinococcus radiodurans to the pressures experienced during an asteroid strike. The microbe survived, suggesting that impacts could spread life from planet to planet. Credit: Lisa Orye/Johns Hopkins University
We expected it to be dead at that first pressure. We started shooting it faster and faster. We kept trying to kill it, but it was really hard to kill.

– Lily Zhao, study lead, John Hopkins University

In fact, so hardy did the bacterium prove, the experiment was halted not because the team eventually killed it – but because the steel plates sandwiching the samples started giving out under the pressure of the gas gun impacts!

Of course, this doesn’t prove that life – or the ingredients of life – came to Earth from Mars or from asteroids. For one thing, we have yet to discover any solid evidence for Mars having once harboured basic life-forms, despite all the evidence it once have the conditions to do so, and they this formed in advance of Earth. There’s also currently no evidence for organics on asteroid having been able to form more complex structures.

However, and on a broad level, it does demonstrate that basic life forms such as bacteria are certainly hardly enough to travel from one place to another – and that if the conditions are just right in the place where they arrive, they might it turn go on to help kick-start more complex life there (assuming the place they arrive doesn’t already harbour some form of basic life which regards them as an invader to be wiped out).

Rockets and Satellites: Proof of Pollution

I’ve written about the growing problem of upper atmosphere pollution resulting from the increasing number of commercial launches around the world, and the potential impact it might be having or come to have on the stratosphere’s weather systems and in damaging things like the ozone layer (in particular, see: Space Sunday: space debris and atmospheric damage + some updates).

Now a team of researchers at the Leibniz Institute for Atmospheric Physics have published the first direct correlation between space vehicle debris re-entering the atmosphere and an increase in atmospheric pollutants – namely lithium.

In February 2025, Spaces launched a Falcon 9 to deliver 22 Starlink satellites to low Earth orbit (LEO). Whilst the upper stage of the rocket successfully delivered its payload to orbit, it suffered a malfunction during a planned de-orbit engine burn which should have lead to its controlled entry into the atmosphere and eventually destruction as it burned-up. As a result, the stage remained orbiting the Earth for 18 day before starting an uncontrolled re-entry some 100 km west of Ireland and proceeding over populated Europe to the point of kindly dropping debris on Poland.

During the event, atmospheric researchers at the Leibniz Institute, Germany, were surveying the upper atmosphere composition using a highly sensitive resonance fluorescence Lidar system when the noticed a sudden and rising spike in upper atmosphere lithium. Normally, lithium exists within the atmosphere to the tune of around 3 atoms per cubic centimetre, but the researchers at Leibniz saw levels climb to some 31 atoms per cubic centimetre at altitudes between 96.8 km and 94.5 km – the range in which Falcon 9 upper stages start to break-up and the risk of pollutant spillage is greatest.

The spike in upper atmosphere lithium (in red) as seen by the researchers at Leibniz Institute, showing its intensity and altitude – the latter of which matches the break-up of a Falcon 9 upper stage. Credit: Robin Wing et al

Intrigued, the atmospheric researchers continued to monitor the rising levels of lithium whilst also running some 8,000 simulations of backward wind paths from the Lidar station to the skies over Ireland. What they found, after eliminating any other potential causes for the spike they could think of, was that it commenced almost exactly at the time the Falcon 9 upper stage entered the Earth’s atmosphere west of Ireland and almost exactly tracked the stage’s passage over Ireland and the UK as it reached its point of initial break-up and fell through to around 94 km altitude, very much tying the plume to the stage’s demise – the upper stage of Falcon 9 rockets using lithium extensively in their components.

Whilst this is the first definitive time a significant increase in atmospheric pollutants has been directly tied to a re-entry event, but doesn’t supply all of the answers. For example, no-one actually knows how such concentrated dumps of lithium – which occur following every Falcon 9 launch and every re-entry of a Starlink satellite (which SpaceX have been disposing an accelerated rate in order to “get rid” of their version 1.x satellites in favour of the v2 unit) – will have on high-altitude weather systems or on other aspects of the atmosphere as they disperse and descend.

An images showing a backtracking of wind paths over Europe at the time of the Falcon 9 upper stage re-entry. Not how the initial track closely follows the track of the upper stage, including the period of maximal lithium dispersion as the vehicle breaks-up between 97 and 94 km altitude. Credit: Robin Wing et al   

However, it is indicative that the commercial launch sector as a whole has a major question to answer in terms of what they should be doing to minimise the potential for damage to our atmosphere they are creating