Tag: NASA

Space Sunday: 1,000 sols and counting

Posted on by Inara Pey
NASA’s Perseverance Mars rover using the WATSON camera mounted on its robot arm to take this “selfie” showing the rover’s camera mast looking at WATSON and the Ingenuity helicopter sitting on the surface of Mars after being dropped there by the rover. This image was r=taken on the 46th sol of the mission (April 6th, 2021). Credit: NASA/JPL/ASU/MSSS

1,000 Martian sols ago, two further ambassadors from Earth arrived on the Red Planet, winched safely down onto the floor of Jezero Crater by a hovering “skycrane”. Since then, both have performed their work near-flawlessly over a period of almost 3 terrestrial years – one doing do for far, far longer than its designers and operators had ever hoped. They are, of course, the Mars 2020 mission rover Perseverance and its companion “Mars Helicopter” Ingenuity.

The mission actually arrived on Mars on February 18th 2021, but the passing of 1,000 sols (as the local Martian day is called) is an excellent opportunity to review the Mars 2020 mission as a whole, and look to the future.

Ingenuity had a planned mission duration of 90 terrestrial days during which it was expected to be able to make up to five flights; no-one really knew how well the craft’s batteries, electronics and mechanical systems would stand up to the hostile conditions on Mars once operations got underway. But as of December 2nd, 2023, the 1.8 kg drone has complete 64 flight and clocked up just over 2 hours of airborne time. In doing so, it has proven that entirely automated flight on other planets without direct human control is possible, and that a small, camera-equipped aerial vehicle can work in tandem with ground units to help reconnoitre potential routes of exploration and identify potential points of scientific interest.

Perseverance, meanwhile, has spent the intervening time studying an ancient river delta within the crater, believed to have formed as water poured down from the plains above early in Mars’ history, depositing clays and other minerals as they gradually flowed outwards and eventually gave rise to a lake within Jezero. The primary mission for the rover has thus far been to explore the delta and seek both evidence of past habitability and search for actual biosignatures indicative of past life. In doing so, Perseverance has gathered 23 air and soil samples, some of which may be returned to Earth in a future (if controversial, in terms of NASA funding) sample-return mission.

In this false-colour image of Jezero Crater, the river that once broached the crater walls and carried water into its basin to form a shallow lake can be seen on the left, with the river’s delta clearly visible on the crater floor. The colours are intended to highlight different mineral deposits within the delta, with green representing the widespread carbonates. Most recently, Perseverance has been exploring the green-tinted area above the main river channel. Credit: NASA/JPL/ASU/MSSS

The data gathered by the rover confirms that Jezero Crater – originally formed some 4 billion years ago via an asteroid impact – was subject to multiple periods of flooding which took place over an extended period commencing several hundred million years after the crater was formed. These periods of flooding initially gave rise to the deposition of sandstone and mudstone in the crater, suggesting a modest lake was created. Later, this lake underwent a more sustained period of cyclic flooding and evaporation, giving rise to the deposition of salt-rich mudstones as the waters expanded and contracted.

At its peak, it is believed the lake was perhaps 35 kilometres in diameter and 30 metres deep. Later, as Mars’ climate became more erratic, the crater was subjected to sudden, violent bursts of flooding from above, with large rocks and boulders from outside of the crater being deposited within it by repeated flash floods before the lake – and all surface water on Mars – slowly vanished, being lost to space through evaporation as the atmosphere was lost, or ras a result of it retreating underground, where it froze.

Of the samples gathered and studies by the rover’s on-board science lab, many carried tantalising markers which might be associated with the formation of basic forms of life. These include carbonates, minerals that form in watery environments often favourable to the development of organic molecules (although the molecules themselves could be the result of either organic or inorganic reactions within the water). The rover has also found quantities of fine-grained silica and deposits of phosphate, both of which have been rich in carbonates, and which are respectively known to both preserve fossilised microbes and help microbes kick-start their life processes here on Earth – although evidence of them doing the same on Mars remains elusive.  Some of the carbonate-carrying phosphates have been found to contain iron, something again associated with life here on Earth.

December 2023 is a key month for Perseverance, as it brings to a close the rover’s fourth science campaign within Jezero Crater and the start of a new endeavour. Commencing in 2024, Perseverance will follow the course of the river bed back towards the crater wall – a distance of around 4 km – to where mission personnel believe they have located an “easy” climb up the crater walls and which intersects the river’s channel at its lower end.

This image of Jezero Crater, captured by NASA’s Perseverance rover, shows the potential route (yellow line) that the robot may take to the crater’s rim. Credit: NASA/JPL/ASU/MSSS

Climbing the crater up to the plains above will expose Perseverance’s science instruments to bedrock and material even older then the outflow plain it has thus far studied, allowing it to reach back to the time the crater was formed. Along the way it will be able to both study the changing rocks and any atmospheric changes as it climbs upwards. As well as analysing the rock samples it gathers, the rover will also store some in the remaining 13 sample tubes contained in its belly, allowing them to be cached together with some of the remaining tubes of material gathered from the crater floor so that an alternate collection of samples can await the arrival of the still-to-be-fully-defined sample return mission, should landing within Jezero itself prove too difficult for the proposed lander part of the mission, and the samples cached there are abandoned.

 Video Promotes Rosalind Franklin

If fortune favours the unfortunate, the next rover to trundle across the surface of Mars will be Europe’s long-awaited Rosalind Franklin. Originally called the ExoMars rover, this vehicle has suffered a number of setbacks during its 20 years in development and pre-flight hell. However, (and touching large amounts of wood, given I have something of a loose association with the mission), things are currently on course for an October 2028 launch, that the European Space Agency felt confident enough to release a new promotional video showcasing the mission.

Some 60% heavier and slightly larger than NASA’s Mars Exploration Rovers Opportunity and Spirit, the European rover is, like them, solar-powered. It also shares a similar mission arc as both of the MER rovers and the nuclear-powered Curiosity and Perseverance: to locate evidence for water on Mars and seek out evidence for past signs of life. However, in one respect its mission does differ, as Rosalind Franklin will also focus seeking evidence for current microbial life on Mars.

To assist with the latter, the rover will be equipped with a drilling mechanism capable of reaching up to two metres beneath the planet’s surface – far beyond depths so far plumbed in the search for evidence of Martian microbial life – with the samples gathered then put through extensive study and analysis by the rover’s multiple science systems.

The landing site for the mission is Oxia Planum, a region located between two outflow channel systems: Mawrth Vallis to the northeast and Ares Vallis to the southwest. Scientists believe this region will contain remnants of the planet’s wetter past, increasing the potential for finding evidence for past or even current microbial life on the planet. Once there – the flight to Mars will take almost exactly 2 years, courtesy of the capabilities of its launch vehicle – Rosalind Franklin will travel up to 70 metres a day when on the move, with an overall primary mission expected to last some 7 months.

Voyager 1 Hits Problems

Humanity’s first interstellar ambassador, Voyager 1, is now just over 47 years into its voyage and more than 162 AU (or 24 billion kilometres) from Earth – and like all of us as we grow older, it is increasingly showing signs of its age. Already, the more energy-intensive science instruments on the lonely spacecraft have been shut down, and engineers have had to repeatedly work their way gingerly around assorted problems the craft has encountered; such is the distance separating vehicle and home planet that even the tiniest errors risks breaking all communications.

An artist’s impression of a voyager probe in deep space. Credit: NASA

Most recently, Voyager 1 has started having issues with two key systems: the Flight Data System (FDS) and the Telemetry Modulation Unit (TMU). The latter is responsible for transmitting to Earth data on the spacecraft’s condition, orientation, etc., together with information from its operational science instruments, and receiving and managing communications from Earth. The data it sends is gathered by the three computers of the FDS, which combine everything obtained from the other instruments and sub-systems into a single package for the TMU to send. Except recently, all the TMU has been sending is a repeating pattern of meaningless binary, although it has continued to act on messages from Earth.

It had been thought the problem lies with the TMU itself, but after careful and painfully slow diagnoses (round-trip communications between Voyager 1 and Earth are on the order of 45 hours); the problem was found to be within the FDS. Over the weekend of December 9th/10th, mission engineers ordered the FDS to perform a sequential restart, which it was hoped would kick-start the system into once again passing meaningful data to the TMU. It didn’t.

Created using NASA’s Eyes on the Solar System, this image shows what it might be like to look back at our solar system from 162 AU

So currently, Voyager 1 remains capable of receiving commands from Earth, but it cannot provide any understandable feedback on whether anything succeeded, or what systems are trying to report back through the FDS. As such, the Voyager mission team have indicated it will take several weeks to formulate a new plan of action in order to try to resolve the problem.

Spaceplanes, Spaceplanes

Both the United States and China were due to launch their highly secretive, automated “spaceplanes” this past week – although as it turned out, only one of them actually did so.

The United States X-37B programme had been due to commence its seventh mission – and the fourth flight of the 2nd of the two X-37B craft the US Space Force and US Air Force jointly operate – on December 14th. It was to be the first flight of the craft atop a SpaceX Falcon Heavy, seen as offering the craft the ability to fly missions at much higher orbits than can be achieved using its over launch vehicles – the ULA Atlas V 501and the Falcon 9 Block 4 -, potentially allowing for more flexible and even longer-duration on-orbit operations.

The USSF / USAF X-37B (vehicle 1), shortly after its return to Earth on November 22nd, 2022, following a 908-day orbital mission. Credit: US DoD

The cause of the delay has not been stated, but appears to have been called by SpaceX rather than the US DoD, and following the postponement, the Falcon Heavy was removed from Pad 39A at Kennedy Space Centre. At the time of writing, no revised launch target has been announced.

China, however, so no such delays in the third flight of its Shenlong “Divine Dragon” spaceplane, which lifted-off from the Jiuquan Satellite Launch Centre on December 14th, as planned, using a Long March 2F booster.

Little is actually known about the Chinese vehicle – although there is an emerging consensus that it is potentially similar in overall size and form to the US X-37B. The craft first flew the craft in September 2020 and then was launched a second time in August 2022 – this mission lasting for 276 days, which is still a small fraction of the time the US craft tends to spend in orbit (908 days on its last mission). That said, the second Shenlong mission did cause surprise and concern in the west when it apparently launch / placed / jettisoned something into space  – China has remained tight-lipped as to what it was.

An artist’s rendering of what the Chinese automated space plane might look like. Credit: Erik Simonsen / Getty

No information on the flight or its potential duration has been given by the Chinese authorities, with the official statement post-launch something of a laconic repetition of the announcements which followed the first two flights of the vehicle.

The test spacecraft will be in orbit for a period of time before returning to the domestic scheduled landing site. During this period, it will carry out reusable technology verification as planned to provide technical support for the peaceful use of space.

– Official and bland Chinese statement following the latest Shenlong launch

That both vehicles were originally intended to launch so close together is not a coincidence. The USSC/USAF has been very open in its desire to learn more about the Chinese vehicle’s purpose and capabilities – and the China probably likewise want to know more about the American vehicle. Thus, having them in space at the same time allows the two nations to observe one another’s craft via Earth-based means and – perhaps – mimic the manoeuvrings of one another’s vehicles.

Space Sunday: lunar delays and planetary dances

Posted on by Inara Pey
The Peregrine Mission One lander on the surface of the Moon, as imaged by Astrobotic Technology, the company responsible for the lander’s design and construction. Credit: Astrobotic Technology

America’s return to the surface Moon as a part of government-funded activities will start in earnest over Christmas 2023, with the launch of the NASA-supported Peregrine Mission One and the Peregrine lander, built by Astrobotic Technology, which will take to the sky on December 24th, 2023 atop a Vulcan Centaur rocket out of Cape Canaveral Space Force Base, Florida.

Originally a private mission, Mission One qualified for NASA funding under the agency’s Commercial Lunar Payload Services (CLPS) in 2018, effectively making it the first lander programme funded by NASA under the broader umbrella of the Artemis programme. In this capacity, the mission will fly 14 NASA-funded science payloads in addition to the original 14 private payloads planned for the mission.

The mission will be the inaugural payload carrying flight for the Vulcan Centaur, with the lander arriving in lunar orbit after just a few days flight – but will not land until January 25th, 2024, the delay due to the need to await the having to wait for the right lighting conditions at the landing site.

I’ll have more on this mission closer to the launch date, but in the meantime, as the Peregrine Mission One launch date is getting closer, the date for America’s return to the Moon with a crewed mission is slipping further away.

The Peregrine Lander (r) will mark the first flight of United Launch Alliance’s (ULA) new Vulcan Centaur launch vehicle (l). Credits: ULA and Astrobotic Technology

In terms of the Artemis crewed programmed, there have been a number of flags raised around the stated time-frame for Artemis 3, the mission slated to deliver the first such crew to the surface of the Moon in 2025, over the past few years. These have notably come from NASA’s own Office of Inspector General (OIG), but similar concerns have also started to be more openly voiced from within NASA.

These concerns largely focus on whether or not SpaceX can provide NASA with its promised lunar lander and its supporting infrastructure in anything like a timely manner, given that SpaceX has yet to actually successfully fly a Starship vehicle. In this, the awarding of the lander vehicle – called the Human Landing System (HLS) in NASA parlance – to SpaceX, who propose using a specialised version of the Starship vehicle, was always controversial. For one thing, Starship HLS will be incapable of being launched directly to lunar orbit. Instead, it will have to initially go to low Earth orbit and reload itself with propellants – which will also have to be carried to orbit by other Starship vehicles.

Infographic produced by Blue Origin highlighting the likely launch requirements for a Starship HLS. Credit: Blue Origin

At the time the contract for HLS was awarded (2021), competing bidders Blue Origin noted that according to SpaceX’s own data for Starship, a HLS variant of the vehicle would require the launch of fifteen other starship vehicles just to get it to the Moon. The first of these would be another modified Starship designed to be an “orbiting fuel depot”. It would then be followed by 14 further “tanker” Starship flights, which would transfer up to 100 tonnes of propellant per flight for transfer to the “fuel depot”. Only after these flights had been performed, would the Starship HLS be launched – and it would have to rendezvous with the “fuel depot” and transfer the majority of propellants (approx. 1,200 tonnes) from the depot to its own tanks in order to be able to boost itself to the Moon and then brake itself into lunar orbit.

Despite such claims being made on the basis of SpaceX’s own figures, SpaceX CEO Elon Musk pooh-poohed  them, claiming all such refuelling could be done in around 4-8 flights, not 16. Despite their own OIG and the US Government Accountability Office (GOA) agreeing with the 16-flight estimation, NASA nevertheless opted to accept Musk’s claim of 4-8 launches, going so far is to use it in their own mission graphics.

A NASA infographic showing the Artemis 3 mission infrastructure. Note the (optimistic)  6 Starship launches required to get the SpaceX Starship HLS to lunar orbit. Credit: NASA/SpaceX

However, the agency appeared to step back from this on November 17th, 2023, when Lakiesha Hawkins, assistant deputy associate administrator in NASA’s Moon to Mars Programme Office, confirmed that SpaceX will need “almost 20” Starship launches in order to get their HLS vehicle to the Moon, with launches at a relatively high cadence to avoid issues of boil-off occurring when storing propellant in orbit.

Now the US Government Accountability Office (GOA) has re-joined the debate, underlining the belief that SpaceX is far from being in any position to make good on its promises regarding the available of HLS. In particular the report highlights SpaceX is still a good way from demonstrating it can successfully orbit (and re-fly) a Starship vehicle, and it has not even started to demonstrate it has the means to store upwards of 1,000 tonnes of propellants in orbit, or the means by which volumes of propellants well above what has thus far been achieved can be safely and efficiently be transferred between space vehicles, and it has yet to produce a even a prototype design for the vehicle.

Nor does the report end there; it is also highly critical of the manner in which NASA has managed the equally important element of space suit design, firstly in awarding the initial contract for the Artemis lunar space suits to Axiom Space – a company with no practical experience in spacesuit design and development –  rather than a company like ILC Dover, which has produced all of NASA’s space suits since Apollo; then secondly in failing to provide Axiom with all the criteria for the suits, necessitating Axiom redesigning various elements of their suit to meet safety / emergency life support needs.

As a result, the GAO concludes that it is likely Artemis 3 will be in a position to go ahead much before 2027; there is just too much to do and too much to successfully develop for the mission to go ahead any sooner. In this, there is a certain irony. When Artemis was originally roadmapped, it was for a first crewed landing in 2028; however, the entire programme was unduly accelerated in 2019 by the Trump Administration, which wanted the first crewed mission to take place no later than December 2024, so as to fall within what they believed would be their second term in office. Had NASA been able to stick with the original plan of 2028, there is a good chance that right now, it would be considered as being “on target”, rather than being seen as “failing” to meet time frames.

Hubble Hits Further Gyro Issues

On November 29th, 2023, NASA announced that the ageing Hubble Space Telescope (HST) had entered a “safe” mode for an indefinite period due to further troubles with the system of gyroscopes used to point the observatory and hold it steady during imaging.

In all, HST has six gyroscopes (comprising 3 pairs – a primary and a back-up),with one of each pair required for normal operations. To help increase the telescope’s operational life, all three pairs of gyros were replaced in the last shuttle mission to service Hubble in 2009, and software was uploaded to the observatory to allow it to function on two gyros – or even one (with greatly reduced science capacity)  should it become necessary.

Today, only 3 of those gyros remain operational, the other three having simply worn out, and on November 19th, one of those remaining 3 started producing incorrect data, causing the telescope to enter a safe mode, stopping all science operations. Engineers investigating the issue were able to get the gyro operating correctly in short order, allowing Hubble to resume operations – only for the gyro to glitch again on November 21st and again on November 23rd, leading to the decision to leave the telescope in its safe mode until the issue can be more fully assessed.

The Hubble Space Telescope. Credit: NASA

The news of the problems immediately led to renewed calls for either a crewed servicing mission to Hubble or some form of automated servicing mission – either of which might also be used to boost HST’s declining orbit. However, such missions are far more easily said than done: currently, there isn’t any robotic craft capable of servicing Hubble (not the hardware or software to make one possible). When it comes to crewed missions, it needs to be remembered that Hubble was designed to be serviced by the space shuttle, which could carry a special adaptor in its cargo bay to which Hubble could be attached, providing a stable platform from which work could be conducted, with the shuttle’s robot arm also making a range of tasks possible, whilst the bulk of the shuttle itself made raising Hubble’s orbit much more straightforward.

Currently, the only US crewed vehicle capable of servicing HST is the SpaceX Crew Dragon – and it is far from ideal, having none of the advantages or capabilities offered by the space shuttle, despite the gung-ho attitude of many Space X supporters. In fact, it is not unfair to say that having such a vehicle free-flying in such close proximity to Hubble, together with astronauts floating around on tethers could do more harm than good.

A further issue with any servicing mission is that of financing. Right now, the money isn’t in the pot in terms of any funding NASA might make available for a servicing mission – and its science budget is liable to get a lot tighter in 2024, which could see Hubble’s overall budget cut.

Continue reading “Space Sunday: lunar delays and planetary dances” →

Space Sunday: happy 65th, NASA!

Posted on by Inara Pey
The NACA and NASA “meatball” logos. Credit: NASA

On October 1st, 1958 the National Aeronautics and Space Administration officially commenced operations, just two months after then-President Dwight D. Eisenhower signed the US National Aeronautics and Space Act into law.

NASA’s birth essentially arose out of what would become known as the “Sputnik crisis”. In October 1957 Russia launched Sputnik 1, the world’s first artificial satellite. Worse, just a month later, they launched Sputnik 2, which not only carried a living animal into orbit (the dog Laika, doomed to expire in orbit as the technology did not exist for the craft to re-enter the atmosphere and land safely), it demonstrated Russia had a launch system vehicle could be used relatively rapidly. This put US space launch efforts – activities largely split between the three branches of the military – into something of a tailspin, with the realisation that any civilian / science space programme could not be reliant on competing military programmes.

To this end, it was decided to place military space development under the auspices of a new agency within the US Department of Defense: the Advanced Research Projects Agency (ARPA – now the Defence Advanced Research Projects Agency, or DARPA), which was also charged with managing all aspects of emerging technologies research as they related to military use. Meanwhile, civilian space research would be placed in the hands of a new agency, with the National Advisory Committee for Aeronautics (NACA) charged with coming up with a structure for that organisation.

A replica of Sputnik-3 on display at the U. S. S. R. Industrial Exhibition, 1958, held in Moscow. The 4-metre long, 1.3 tonne spacecraft was 100 times the mass of its American counterpart, Explorer-1, and its launch and that of the earlier Sputnik-1 and Sputnik0–2 missions did much to speed the creation of NASA. Credit: Pathé News

Further haste was given to the need to determine the best direction of the US civilian space programme in May 1958, when Russia launched Sputnik-3 to mark the International Geophysical Year. Massing 1.3 tonnes, or 100 times that of the US satellite launched 3 months earlier with the same goal, Sputnik-3 demonstrated Russia had a payload to orbit capability well beyond anything within the United States, and a technical capability to fly large suites of science instruments on a single vehicle (12 instruments in the case of Sptnik-3).

In being instructed to study options for a new civilian space agency, the NACA was uniquely placed. Founded in 1915, it had (at that time) been at the forefront of aviation development in the United States for more than forty years, and following the end of the Second World War, it had become increasingly involved in aerospace research. For example, NACA was responsible for the initial design concept of what would become the X-15 hypersonic aircraft after developing and flying a number of supersonic craft during the early 1950s, and worked with the US Air Force to develop the vehicle from 1954 through until the establishment of NASA in October 1958.

A 1952 photograph of the NACA High Speed Test Force at Edwards Air Force Base during flights of the Douglas D-558-2 Skyrocket, the first aircraft to exceed Mach 2.0 (November 1953). Credit: Armstrong Photo Gallery.

After due consideration, NACA submitted a report and after reading it, James Killian, the then-chair of the Science Advisory Committee realised that NACA was not only well-placed to recommend what form the new space agency should take, it was ideally placed to become the foundation of the new organisation, informing Eisenhower via a memorandum the to Eisenhower stating the new agency should be formed out of a “strengthened and re-designated NACA, a going Federal research agency with 7,500 employees and $300 million worth of facilities” and which could expand its role “with a minimum of delay”. His suggestion was accepted and incorporated into the National Aeronautics and Space Act.

As a result of the decision to transition NACA into NASA, the new agency was able to hit the ground running, gaining three major research centres – Langley Aeronautical Laboratory, Ames Aeronautical Laboratory, and Lewis Flight Propulsion Laboratory, and the NACA budget and staff. In the months immediately following NASA’s establishment, those elements of the US Army and US Navy trying to build and operate orbital rocket systems were transitioned over to the new agency (including the US Army team utilising Wernher von Braun and other former German rocket engineers), together with the California Institute of Technology’s Jet Propulsion Laboratory, which has become world-famous as the developmental and mission operations centre for the majority of NASA’s robotic deep space missions.

As a part of its very first research activities, NASA took over the hypersonic X-15 programme mentioned above, overseeing all 199 flights of that craft along with the US Air Force. At that time NASA came into existence, the NACA and the USAF had been collaborating on the idea of extending the X-15 into an orbit-capable vehicle to be launched vehicle a family of modified missiles, thus allowing the US to gain valuable insight into the design requirements and operating nature of space-capable aircraft, which were even at that time being seen as the future of manned spaceflight.

Conceptual illustrations of the X-15B orbital vehicle with various launch options, and (r) the X-20 Dyna-Soar. Credit: Mark Wade

In particular, the USAF was keen to gather data to help with a  concept for a multi-role “space glider” which would evolved into the X-20 Dyna-Soar project of the early 1960s (although this was ultimately cancelled in 1963). However, NASA’s new leadership preferred a more cautious approach to putting men in space, determining primates should be flown first and recovered for post-flight study. Therefore, the X-15B concept, with its need for a skilled pilot at the controls, was rules out in favour of the less capable but easier to fly Mercury capsule. Thus was NASA’s manned spaceflight programme born.

Today, whilst still a relatively small organisation in terms of manpower when it comes of federal agencies (the Federal Aviation Administration, for example, numbers 48,000 employees to NASA’s 18,000), and with a modest budget (less than US $26 billion from the US mandatory federal budget of US $4.1 trillion – which admittedly and conversely is still around 4.5 times more than the FAA’s), NASA is an incredibly diverse and far-reaching organisation.

NASA’s rarely-noted administration headquarters at 300 E Street SW, Washington DC. Credit: NASA (1997)

Not only does it manage all of America’s civilian space activities through ten major research and operations centres across the United States (as well as numerous smaller facilities and centres), it continues to carry out wide-ranging aeronautical research and development in what is a continuance of the cutting-edge work started by the NACA more than 100 years ago.

In addition, NASA is involved in R&D and operations across many disciplines and areas of research, including communications; vehicle and transportation safety; environmental monitoring (climate and weather in partnership with the National Oceanic and Atmospheric Administration (NOAA); pollution control, environmental management, global land use, deforestation monitoring, agricultural monitoring, etc (much in partnership with the US Geological Survey, or USGS); research into alterative and sustainable energy systems; nuclear research; multiple avenues of general science research as they pertain to the planet and to healthcare; and in promoting education, science, mathematics and the harnessing of technology through a range of STEM initiatives in the US and around the world.

So, happy anniversary NASA. You may be at retirement age in human terms – but here’s to many more!

Updates

OSIRIS-REx Samples

Previously on Space Sunday (as they say on TV shows) NASA’s ORISIS-REx mission returned to Earth samples captured from 101955 Bennu, a carbonaceous near-Earth asteroid. As we left that story, the sealed capsule containing the estimated 250 grams of material was pending a transfer to NASA’s Johnson Space Centre (JSC), Texas.

The first glove box unit at the ARES facility, JSC, purpose-built to handle the disassembly of the ORISIS-REx sample return capsule so that the samples of asteroid Bennu it contains can be removed for examination and analysis. Credit: NASA / Robert Markowitz

That transfer occurred on Tuesday, September 26th, 2023, with the sample capsule being airlifted from the US Army’s Dugway Proving Ground in Utah, some 31 kilometres from where it landed, to Ellington Field Joint Reserve Base near Houston, Texas. From here the special transpiration container with the capsule inside was move by road to the Astromaterials Research and Exploration Science (ARES) centre at JSC.

ARES is home to the world’s largest collection of “astromaterials” (samples returned from space), and is usually the first US centre to examine such samples brought to Earth by US space missions. As such, it is the ideal permanent home for the OSIRIS-REx samples, and will be the centre that carries out an initial sample analysis and then divvy it up for distribution to research centres around the world and to museums.

How it should have gone – the OSIRIS-REx TAGSAM “touch-and-go” mechanism recovering samples from the surface of asteroid 101955 Bennu in 2020. As it turned out, the asteroid’s surface was so brittle, the sample head and arm smashed through it to a depth of around 50cm.

Continue reading “Space Sunday: happy 65th, NASA!” →

Space Sunday: the return of OSIRIS-REx

Posted on by Inara Pey
The OSIRIS-REx Sample Return Capsule (SRC) in the landing zone at UTTR, September 24th, 2023. Credit: NASA TV

On September 8th, 2016 at 23:05 UTC, an Atlas V 411 rocket lifted-off from Space Launch Complex (SLC) 41, Cape Canaveral Air Force Station (now Space Force Station). Launched by United Launch Alliance (ULA), the rocket carried aloft NASA’s Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx), an ambitious mission to study a carbonaceous near-Earth asteroid and obtain as large a sample of material as possible for a return to Earth.

More recently, on September 24th, 2023, the mission achieved its goal, returning an estimated 250 grams of material – four times the minimum amount scientists hoped to obtain at the start of the mission – from the 500m diameter asteroid 101955 Bennu. It is not the first mission to return a sample of material from an asteroid; Japan holds that record with its Hayabusa and Hayabusa-2 missions. The first rendezvoused with asteroid 25143 Itokawa in 2005, the second with asteroid 162173 Ryugu in 2018; however, given both these missions returns a total sample cache of under 6 grams, OSIRIS-REx is the most successful to date.

A ULA Atlas 5 launches OSIRIS-REx on its way to a rendezvous with asteroid Bennu

Over the intervening seven years since its launch and return, OSIRIS-REx completed a round-trip journey of some 6.4 billion kilometres. Along the way it performed a fly-by of Earth some 12 months after launch, allowing it to enter an orbit around the Sun from which it could intercept Bennu. This passage around the Sun allowed OSIRIS-REx to past through the Earth-Sun Lagrange L4 position, where it performed a search for a class of near-Earth objects known as Earth-Trojan asteroids. Whilst no previously unknown asteroids were located during the 11-day survey in February 2018, the exercise yielded valuable data on vehicle manoeuvring for the kind of precise imaging required on reaching Bennu.

As it approached OSIRIS-REx Bennu in late 2018, OSIRIS-REx was able to observe Jupiter, adding to his science mission, prior to entering an initial orbit at the start of December 2018. It then spent most of the month generally characterising the asteroid, detecting hydrated minerals in the form of clay across the asteroid’s surface, suggesting it was once a part of a larger object rich with frozen water, offering a further pointer to how life-forming minerals and water may have been carried to Earth and the inner planets.

On December 31st, 2018 OSIRIS REx closed to just 1.75 km above Bennu’s surface, allowing it commence an extensive remote mapping and sensing mission which allowed the science team to identify potential areas which might be suitable for gathering one or more samples. In reaching that altitude, OSIRIS-REx set a new record for the closest distance any spacecraft has orbited a celestial object, beating ESA’s Rosetta mission’s orbit of 7 km around the comet 67P/Churyumov–Gerasimenko.

In all, 14 months were spent carefully surveying Bennu, allowing for potential sample-gathering sites to be identified, with the spacecraft closing to just 1 km above the asteroid, breaking its own record and allowing a final survey of the four preliminary landing sites so a final selection could be made. In the end, a site dubbed “Nightingale”, a fairly open shallow depression on the asteroid’s surface, was selected, and the mission moved to the rehearsal phase.

Image sequence showing the rotation of Bennu, imaged by OSIRIS-REx at a distance of around 80 km. Credit: NASA Goddard

In order to collect samples, OSIRIS-REx had to make physical contact with the asteroid in a “touch and go” (TAG) manoeuvre. This would see the spacecraft deploy a robot arm underneath itself. Called the Touch-And-Go Sample Arm Mechanism or TAGSAM, this spring-loaded arm carried a camera system and, on its end, a sample gathering system. The craft would then use its thrusters to gently push itself down towards Bennu, bringing the sample head into contact with the asteroid’s surface.

At this point, several things would happen in rapid succession: the springs in the arm would absorb the spacecraft’s motion, allowing it to maintain contact for a second or two as a jet of inert nitrogen would be directed at the surface under the sample head in order to blast material up into it while Velcro-like rings on the end of the head would snag dust particles and the like. Then, as the springs in the arm recoiled under the mass of the spacecraft and very gently push it back away from the asteroid, allowing a Mylar cap to close over the sample head, trapping whatever had been captured inside the head. Finally, once the spacecraft was sufficiently clear of the asteroid – 40m or so -, OSIRIS-REx would fire its thrusters an position itself back in orbit a few hundred metres above the asteroid, where the sample gathering operation could be assessed for success and from which, if required, a further attempt made to grab material.

A computer simulation of OSIRIS-REx making contact with asteroid Bennu. Credit: NASA

All of this was obviously quite complex – and due to the the delay in communications between vehicle and Earth, had to be carried out entirely autonomously. Hence the rehearsal phase of the mission. These were carried out in April and August 2020, with the first bringing the craft to within 65 metres of the sample site and the second stopping just 40 metres above it. Both saw the craft go through all phases of the TAG operation, sans actually touching the asteroid, with a small burst from the thrusters substituting from the recoil of the TAGSAM springs to push it away from the asteroid once more. Both rehearsals were flawless and paved the way for the first – and only, as it turned out – sample gathering attempt.

Continue reading “Space Sunday: the return of OSIRIS-REx” →

Space Sunday: a DART plus JWST and TRAPPIST-1 updates

Posted on by Inara Pey
NASA’s Double Asteroid Redirection Test (DART) vehicle under thrust as it closes on the asteroid Dimorphos as it orbits Didymos. Credit: NASA

On November 24th, 2021, NASA launched the Double Asteroid Redirection Test (DART) mission, a vehicle aimed at testing a method of planetary defence against near-Earth objects (NEOs) the pose a real risk of impact.

I’ve covered the risk we face from Earth-crossing NEOs – asteroids and cometary’s fragments that routinely zoom across or graze the Earth’s orbit as they follow their own paths around the Sun. We are currently tracking some 8,000 of these objects to assess the risk of one of them colliding with Earth at some point in the future. This is important, because it is estimated a significant impact can occur roughly every 2,000 years, and we currently don’t have any proven methods of mitigating the threat should it be realised. And that is what DART is all about: demonstrating a potential means of diverting an incoming asteroid threat.

Developed as a joint project between NASA and the Johns Hopkins Applied Physics Laboratory (APL), DART is specifically designed to deflect an asteroid purely through its kinetic energy; or to put it another way, by slamming into it, and without breaking it up. Both are important, because by simply slowing an Earth-crossing NEO along its orbit, we give time for Earth to get out of its way; then, by not causing it to break, then we avoid the risk of it becoming a hail of shotgun pellets striking Earth at some point further into the future.

The DART mission. Credit: NASA

The target for the mission is a binary asteroid 65803 Didymos (Greek for “twin”), comprising a primary asteroid approximately 780 metres across, and a smaller companion called Dimorphos (Greek: “two forms”) caught in a retrograde orbit around it, with both orbiting the Sun every 2 years 1 month, periodically passing relatively close to Earths, as well as periodically grazing that of Mars.

Discovered in 1996 by the Spacewatch sky survey the pair has been categorised as being potentially hazardous at some point in the future. At some 160m across, Dimorphos is in the broad category of size for many of the Earth-crossing objects we have so far located and are tracking, making it an ideal target.

DART actually started as a dual mission in cooperation with the European Space Agency (ESA) called AIDA – Asteroid Impact & Deflection Assessment. This would have seen ESA launch a mission called AIM in December 2020 to rendezvous with Didymos and enter orbit around it in order to study its composition and that of Dimorphos, and to also be in  position to observe DART’s arrival in September 2022 and its impact with the smaller asteroid.

However, AIM was ultimately cancelled, leaving NASA to go ahead with DART. To reduce costs, NASA initially looked to make it a secondary payload launch on a commercial rocket. But it was ultimately decided to use a dedicated Falcon 9 launch vehicle for the mission, allowing it to make its September 2022 rendezvous with Dimorphos.

An artist’s impression of DART and the LICIACube cubesat, with Dimorphos and Didymos in the background. Credit: NASA

In order to impact the asteroid at a speed sufficient to affect its velocity, DART needs to be under propulsive power. It therefore uses the NEXT ion thruster, a type of solar electric propulsion that will propel it into Dimorphos at a speed of 6.6 km/s – which it is hoped will change the velocity of the asteroid by 0.4 millimetres a second. This may not sound a lot, but in the case of hitting an actual threat whilst it is far enough away from Earth, it is enough to ensure it misses the planet when it crosses our orbit.

This motor is powered by a deployable solar array system first deployed to the International Space Station (ISS). However, what is most interesting about these solar panels is that a portion of them is configured to demonstrate Transformational Solar Array technology that can produce as much as three times more power than current solar array technology and so could be revolutionary should it reach commercial production.

Accompanying DART is Light Italian CubeSat for Imaging of Asteroids (LICIACube), a cubesat developed by the Italian Space Agency, and which  will separate from DART 10 days before impact to acquire images of the impact and ejecta as it drifts past the asteroid. To do this, LICIA Cube will use a pair of cameras dubbed LUKE and LEIA.

As the cubesat is unable to orbit Didymos to continue observations, ESA is developing a follow-up mission called Hera, Comprising a primary vehicle bearing the mission’s name, and two cubesats, Milani and Juventas, this mission will launch in 2024, and arrive at the asteroids in 2027, 5 years after DART’s impact, to complete a detailed assessment of the outcome of that mission.

 ISS Gets a New Module

On November 26th, 2021, a new Russian module arrived at the International Space Station (ISS).

The Prichal, or “Pier,” module had been launched by a Soyuz 2.1b rocket out of the Baikonur Cosmodrome in Kazakhstan two days earlier. Mounted on a modified Progress cargo vehicle, the module was successfully mated with the Nauka module which itself only arrived at the station in July, at 15:19 UTC.

Carried by a Progress vehicle, the Prichal module approaches the ISS. Credit: NASA TV

The four-tonne spherical module has a total of six docking ports, one of which is used to connect it with Nauka, leaving five for other vehicles. However, when first conceived, the module was also intended to be a node for connecting future Russian modules.

But since that time, the Russian space agency, Roscosmos, has abandoned plans to support the ISS with additional modules. Instead, with relations with the west continuing to cool and the ongoing rise in nationalism in Russia, the agency has indicated it plans to orbit its own space station. This being the case, Prichal is viewed as the final element in the Russian segment of ISS, and potentially the first of the new station.

Unlike the arrival of Nauka in July, Prichal managed to dock with the ISS without the additional “excitement” of any thruster mis-firings. Now, the Progress carrier vehicle will remain attached to the module through until December 21st, allowing time for the Russian cosmonauts on the station to carry out a spacewalk to attach Prichal to the station’s power systems. Once it has been detached, the Progress vehicle will be set on a path to burn-up in the Earth’s atmosphere.

Visible over the top of a Progress resupply vehicle, the Prichal module and its Progress carrier can be seen docked with the nadir port of the Nauka module. Credit: NASA TV

As well as expending the docking facilities at the ISS, Prichal delivered some 2.2 tonnes of cargo and supplies to the station. The module will formally commence operations in its primary role in March 2022 with the arrival Soyuz MS-21.

Continue reading “Space Sunday: a DART plus JWST and TRAPPIST-1 updates” →

Space Sunday: Debris, Artemis delays, SpaceX Plans

Posted on by Inara Pey
The International Space Station. Credit: NASA

Anyone  who follows news on space activities will be aware that on November 15th, Russia carried out the test of an anti-satellite(ASAT) missile system that resulted in the destruction of a defunct Soviet-era electronic signals intelligence (ELINT) satellite – and required the crew of the International Space Station (ISS) to move to their respective Earth return vehicles (Soyuz MS-19 and Crew Dragon Endurance) due to risk of being hit by the debris.

To be clear, ASAT systems are not new. The United States and Russia (/the Soviet Union) have between them spent decades developing and testing such systems (the last successful US test was in 2006, with both the USAF and USN having significant ASAT capabilities), and China and India have also demonstrated ASAT systems as deliberate demonstrations of force.

However, the November 15th test by Russia was somewhat different. Occupying a polar orbit at an average altitude of around 470 km, the 2.2 tonne Kosmos 1408 as both a substantial target risking a massive debris cloud, and routinely “passed over” the orbit of the ISS (ave 420 km), putting it at clear risk.  Nor did Russia give any forewarning of the test.

Instead, the US Space Command only became aware of what had happened after they tracked the missile launch all the way to impact – and then started tracking the cloud of debris. This presented no danger to the ISS in its first orbit, but tracking showed it was a very define threat to the station on its 2nd and 3rd orbits, prompting mission controllers to order the ISS crew to start shutting down non-essential operations and sealing-off hatches between the various science modules.

Some 15 minutes before the second pass of the debris field across the station’s orbit, controllers called the station to order the US / European astronauts in the “US section” of the station to secure all remaining hatches to minimise the risk of explosive decompression in the event of a hit, and evacuate to Crew Dragon Endurance both in case an emergency undock was required, and because it presented a significantly smaller target for any stray debris travelling at 28,000 km. The controllers also noted the Russia cosmonauts on the station were engaged in similar actions, and would be retiring to their Soyuz MS-19 vehicle.

In all, the crews were restricted to their Earth return vehicles for somewhere in the region of 3-3.5 hours before it was considered the most significant risk of and impacts had for the most part passed. Even so, it was not until November 17th that all hatches on the ISS were unsealed to allow normal operations to resume throughout all modules. Currently, NASA is still monitoring the situation and may postpone  a spacewalk planned for November 30th as a result of the debris risk.

Ironically, on November 11th, the ISS had to raise its orbit somewhat using the thrust from a docked Progress re-supply vehicle in order to completely remove the risk of debris from 2007 Chinese ASAT weapon test striking it, 14 years after the test.

In these images, Kosmos 1408 can be seen ringed on the left. The image on the right highlights some of the larger clumps and pieces of debris left after the kinetic “kill” by the Russian ASAT weapon. Credit: Numerica and Slingshot Aerospace

Following the test, Russia attempted to play down the risk, stating it posed “no threat” to other orbital vehicle, crewed or uncrewed – a less than accurate statement. Analysis of the debris cloud by both US Space Command and civilian debris tracking organisations reveals much of the cloud will remain a threat for the next several years – if not decades – as the convoluted nature of orbital mechanics and impact velocity gradually increases the cloud’s orbital altitude for a time as it continues to disperse, putting satellites in higher orbits at risk – particularly the likes of the SpaceX Starlink and the OneWeb constellations.

Russia has demonstrated a deliberate disregard for the security, safety, stability, and long-term sustainability of the space domain for all nations. The debris created by Russia’s DA-ASAT will continue to pose a threat to activities in outer space for years to come, putting satellites and space missions at risk, as well as forcing more collision avoidance manoeuvres.

– U.S. Army General James Dickinson, Space Command.

Some 1500 individual pieces of debris from the test are of a trackable size, with potentially tens of thousands more that are too small to be identified. Tim Flohrer, head of the European Space Agency’s (ESA) Space Debris Office noted that the test means that debris avoidance manoeuvres made by satellites in the 400-500 km orbit range may increase by as much as 100% for the next couple of years before the threat is sufficiently dissipated. One of the biggest risks posed by this kind of action is the Kessler Effect (or Kessler Syndrome), wherein debris from one impact causes a second impact, generating more debris, and so setting off a chain reaction.

Given its size and orbit, there is simply no way Russia was unaware of the threat posed by Kosmos 1408 to low-orbit vehicles – particularly crewed vehicles and facilities – if the test was successful. As such, some have seen it as irresponsible due to the impact it could have on general orbital space operations, while others see it as a sign of aggressive intent on Vladimir Putin’s part.

Currently, Russia has not indicated as to whether this was a one-off incident (a previous test in 2020 missed its target), as has been the case in the US, Chinese and Indian tests, or if it could be a part of a wide series of tests. If the latter, then international relationships are liable to be further strained.

NASA OIG: No Moon Landing Before 2026

Following NASA’s indication that the first Artemis lunar laying won’t come “earlier” that 2025, the agency’s own Office of Inspector General (OIG) has thrown a bucket of realism over the entire project, pretty much confirming comments made in this blog concerning vehicle development timelines, whilst also questioning the sustainability of the programme.

Having carried out an extensive audit of the programme, OIG has issued a 73-page report which critiques the current Artemis programme and time frames, although it can only offer suggestions on what might be done, not instigated changes.

Artemis 3 mission (1): the OIG report outlines the first mission to return 2 humans to the Moon – Artemis 3 – as designed by NASA / SpaceX. This uses the SpaceX Starship HLS – which will now be supported by a SpaceX “fuel depot” (a modified Starship hull) sitting in Earth orbit, and frequently refuelled by between 4 and 8 additional Starship vehicles – and the Orion MPCV for transporting a crew of 4 forth and back between Earth and the Moon. Credit: NASA / NASA OIG

It terms of the development of the Human Landing System (HLS), required to get crews to / from the surface of the Moon, the report follows what has been noted in Space Sunday: the 4-year development time frame is simply unrealistic. In particular, the report notes that even in partnerships such as the Commercial Crew Programme, NASA tends to require around 8.5 years to develop a new spaceflight capability – more than double that allocated for HLS (in fact, NASA / SpaceX believed Crew Dragon could be developed and ready for operation in 6 years – it took 10). It also indicates that while a reliance on a single vehicle design / contractors (currently SpaceX) reduces costs, it also places further risk on the entire programme time fame and operations.

Further, the OIG report states that realistically, the first flight of the first Space Launch System (SLS) rocket is unlikely to take place until mid-2022; somewhat later than NASA is still projecting (early 2022). It goes on to point of that given the delays on Artemis 1, it is unlikely that the Artemis 2 mission scheduled for 2023 and which will fly a crew around the Moon and back to Earth in a manner akin to Apollo 8 is unlikely to be ready until mid-2024, simply because NASA plan to re-use elements from the Artemis 1 Orion vehicle in the Artemis 2 Orion, and these will need a comprehensive post-flight examination and refurbishment.

Artemis 3 (2): The report shows the rendezvous with the HLS for the surface mission (2 crew), and leaps ahead to future missions and the establishment of the Lunar Gateway station. What is left unclear is whether the HLS vehicle will be reused (returning it to be refuelled) or simply abandoned (marking it as a waste). Credit: NASA / NASA OIG

Beyond this, the report also raises concerns whether the space suit required for lunar operations – the Exploration Extravehicular Mobility Unit (xEMU) – will actually be ready for operations in 2025, issues in technical development, and in NASA flip-flopping between in-house and commercial contract development of the suit being pointed to as reasons for the delays.

The biggest critique in the report, however, is related to costs. The OIG report notes that at current levels of expenditure, Artemis will cost US $93 billion by 2025/26, with the first four Artemis SLS / Orion launches (Artemis 1 through 4) alone costing US $4.1 each – and this estimate does not include the development of the actual HLS system or the costs to launch / operate it.

NASA OIG estimates the Space Launch system will cost US $4.1 billion per launch for the 1st four flights, with total Artemis development and infrastructure costs (excluding HLS) being some US $93 billion by 2026. Credit: NASA

To reduce these costs, OIG suggests looking to alternate launch vehicles  to deliver crews to lunar orbit, but NASA management has already rejected such ideas and had refuted OIG’s cost analysis and call for most closely accounting for expenditure. However, it has accepted the report’s other concerns; although it will take time to see if this translates into any form of re-assessment of the programme as a whole.

Continue reading “Space Sunday: Debris, Artemis delays, SpaceX Plans” →