SpaceX Starbase, Boca Chica, September 7th, 2021: to the left, Booster 4 stands on the launch table, the launch support tower standing over it. To the top right is Starship 20 sitting on sub-orbital pad B, with the lower half of Booster 3 (the upper tank section of which was cut off and removed in August. Credit: RGV Aerial Photography
SpaceX is continuing to move towards a first flight-test ready stack of its massive Super Heavy vehicle and a proof-of-concept Starship payload carrier – although there is still some way still to go before an actual launch attempt can be made.
Following the test stacking of Booster 4 and Starship 20 on the launch table back in August (see Space Sunday: the Ups and Downs of Space Vehicle Development), Booster 4 was rolled back to the production facilities at the company’s Starbase centre at Boca Chica, Texas, to undergo a number of revisions.
Chief among these has been modification to the vent valve system, nominally used to allow excesses gaseous oxygen and methane to be vented from the rocket’s tanks as it naturally “boils off” due to temperature differentials the vehicle experiences when fuelled ahead of a launch. In particular, the vents for the booster’s lower tank now have covers that direct any gas downwards along the rocket’s body, and the vents for the upper tank force the gas outwards and away from the rocket.
Booster 4 re-departs the production facilities at Starbase to drive the 1.5 km down the road to the launch facilities Credit: StarshipGazer.com
This suggests that SpaceX plan to use the release of gas from the tanks as a means to help control the orientation of the rocket during its descent back through the atmosphere in a manner similar to a more traditional reaction control system (RCS). If this proves to be successful, it means SpaceX have further reduced Super Heavy’s mass by avoiding the need for separate RCS systems and tankage.
Another issue with rockets is that as the fuel tanks empty they lose internal pressure, and this can interrupt the steady flow of propellants to the engines. To prevent this, most launch systems utilise a reserve of helium that can be fed into the tanks as the propellants are burnt, maintaining the necessary tank pressure. To remove the mass created by a helium system, SpaceX have opted to use the rarer option of autogenous pressurisation. This draws a small flow of heated propellants before they reach the engines, and feeds this flow – in gaseous form – back up the outside of the rocket via dedicated pipes to be returned to the fuel tanks to re-pressure them.
The new vent systems and the piping of the autogenous pressurisation feeds where clearly visible as Booster 4 was rolled back to the orbital launch facilities on Tuesday, September 7th, and hoisted back onto the launch table, with the speculation iit may remain there until the actual launch attempt.
Two views of Booster 4 showing the revised excess gas vents from the top of the lower tank tank and the autogenous pressurisation feed pipes, Also visible is the black mass of the QD Arm. Credit: What About It
When this will be is unclear; the operation to hoist the booster into position showed the launch table itself is still being completed, being wrapped in scaffolding. It’s also not clear how much of the necessary propellant and electrical feeds have been installed in the launch support tower – although the Quick Disconnect (QD) arm that actually feeds propellants into the starship vehicle and provide it and the booster with electrical power has been installed (with further additions to come). Similarly, the actual tank farm that will supply consumables – water, propellants, etc., – to the pad to enable launches.
Even so, SpaceX CEO Elon Musk has suggested an initial static fire test with Booster 4 could come within the next week. Even if the majority of the required plumbing, etc., is in place, this seems possibly ambitious, given that such a test will likely only come after at least one each of cryogenic propellant loading / pressurisation tests to ensure the system is ready for any static fire test.
How many static fire tests might be run is unclear; its unlikely that SpaceX will want to fire all 29 engines in the first test but will likely build up to it – perhaps starting with the three motors at the centre of vehicle, followed by a firing of all nine of the middle engines before progressing to firing all 29 engines. And it should be remembered any of these tests, from pressurisation through the engine firings, could result in the rocket sustaining damage or even being completely destroyed.
Booster 4 being gently lowered into the launch table ring mount at the Starbase orbital launch pad. Notes the amount of construction scaffolding still in place. Credit: Nic Ansuini / NASASpaceflight.com
After the August stack test, Starship 20 was moved from the the orbital launch pad to sub-orbital launch pad B, where it has been undergoing an extensive examination of its thermal protection system (TPS) designed to protect it during entry into the atmosphere. The tiles on this system appear to have suffered more than the anticipated amount of stress / damage due to it being lifted up onto the booster by its snout in order to be stacked on the booster, requiring a lot of them to be replaced and others refitted / re-aligned. This work is now drawing to a close, but does point to a need for the tile system to be more robust during vehicle moving / operations.
Most recently, the vehicle has been receiving the six Raptor motors that will power it. This has sparked speculation that once this work is complete, Starship 20 could be ready to start its cryogenic and fuel pressurisations tests ahead of static firing test – again, possibly the inner three first, then all six.
How it started and how it is going: two shots indicating the number of Starship 20 heat shield tiles that needed to be completely replaced (red tags) or which required refitting / realigning (green tags) following the operation to stack and remove the vehicle on its booster in August. Credit: NASASpaceflight.com
A final element key to any launch attempt (and the full booster static fire test) is the granting of permission and a licence by the Federal Aviation Administration, which appears to be rightly determined not to be rushed into giving the OK whilst it is still conducting an extensive review of the Starbase facilities and their overall suitability for Super Heavy / starship launches in the event of an accident (particularly after the airborne explosion of SN11in march 2021 resulted in debris falling to earth 8 km from the SpaceX facilities and close to a populated area).
The ISS as of September 2021, showing the newly-arrived SpaceX CRS 23 resupply vehicle docked alongside the Crew Dragon Endeavour. At the far end of the station are the Russian modules: the recently-arrived Nuaka, Zvezda and Zarya, which has been found to have small fissures in its outer skin. Credit: NASA
Some sections of the tabloid media became excited this week about “cracks” being discovered “on the International Space Station”, with one or two predicting the end of the ISS is now nigh.
The cause of the reports was the announcement by Energia NPO, the company responsible for fabricating the Russian-built elements of the ISS, that “superficial fissures” have been found in the outer skin of the Zarya module.
The Zarya module imaged from the space shuttle Endeavour in December 1998, as the shuttle approach the module in preparation to attach the US Unity module. Credit: NASA
Zarya – also called the Functional Cargo Block (FCB) – was the first module of the ISS to be launched (November 1998), and was initially responsible for providing electrical power, storage, propulsion, and guidance to the ISS during the early years of assembly. However, as more specialised units, notably the Russian Zvezda module (attached to the aft end of Zarya), were launched, the role of the Zarya module has been gradually downgraded to the point where today it is primarily used for internal and external storage space.
Thus far, neither NASA nor Roscosmos have indicated whether or not the fissures have caused any internal pressurisation issues for the station. However, similar fissures – likely the result of exposure to extremes of temperature as the ISS passes between direct sunlight and the cold shadow of Earth and back every 45 minutes – were discovered on the Zvezda Module in 2019, and despite repairs in 2020 and 2021, they continue to be an annoyance.
Whether the Zarya fissures will become a similar issue can only be determined in time – but they are a reminder that while the ISS is not in imminent risk of a major failure, it is genuinely showing its age, particularly the three original modules – Zvezda, Zarya and Unity – all of which are at least 25 years old (including fabrication / construction time), and are potentially becoming increasingly vulnerable to fatigue. Such issues might also cause Russia to make further noises about withdrawing from the ISS after 2024, this time of the grounds of the station’s increasing age, so they can start work on their own space station.
The Accident – the Strangest Brown Dwarf
Brown Dwarfs are sometimes called “failed stars”, in that they have a mass that sits above the most massive gas giant planets we have so far discovered, but below that of the smallest stars. This leaves them incapable of achieving hydrogen fusion, hence the idea they have “failed” as stars. However, they are massive enough to give off considerable infra-red radiation, which tends to point to them being extremely old.
In reviewing data returned by the Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE), citizen scientist Dan Caselden has discovered the strangest brown dwarf to so far be discovered – so strange it has been given the nickname “The Accident”.
Located around 50 light years from Earth, it is officially called WISEA J153429.75-104303.3 and classified a Class Y substellar object – the oldest and coolest classification of such brown dwarfs. All of which is really not that interesting; astronomers have discovered many brown dwarfs in local space around our solar system over the last 30 years.
A comparison between a “typical” brown dwarf and other stellar and planetary objects. Credit: NASA
What is strange about The Accident is firstly, it is spinning about its axis at a speed of 200 kilometres a second (that’s 720,000 km/h)- 25% faster than the next fastest stellar object of its kind.
The second – and more intriguing – thing is that The Accident has the oddest brightness pattern of any brown dwarf. Due to their nature, these objects only give off light in the infra-red wavelengths, and The Accident’s output is – at least in part – at the end of that part of the spectrum that points to it being really old: perhaps 13 billion years old – almost as old as the galaxy itself (13.6 billion years. This extreme age is also supported by The Accident’s rotational speed, something that could only be achieved via thousands of encounters with massive stellar objects down the aeons.
But there’s a twist: The Accident is not consistent in its infra-red brightness, as it also “shines” in parts of the infra-red that indicate that it is a lot, lot, younger than the other data suggest, making the object an anomaly – and accident of nature, so to speak, hence its nickname. This difference in brightness has puzzled scientists, and has led to The Accident starting to get a lot of attention to determine what might be going on inside it.
Some of this attention is also devoted to studying it on the basis of its age – if it really is 13 billion years old, then it formed at a time when the galaxy was a very different place in terms of chemistry, a time when many elements we take for granted (carbon and methane being just two) simply could not exist. Thus, understanding its nature and composition could reveal more about the galaxy’s formation and birth. What’s more, that so strange an object should be found so relatively close to Earth suggests there could be many of these unusual brown dwarfs awaiting discovery.
Virgin Group Ups and Downs
Sir Richard Branson is having some ups and downs in his space endeavours.
The ups are with Virgin Orbit, the smallsat launching service that uses the LauncherOne rocket, lifted to altitude by a modified 747 before being launched, to place payloads of up to 300 KG to a Sun-synchronous orbit or 500 KG to low Earth orbit.
Following the first successful launch of a commercial payload to orbit at the end of June, the company has now passed a critical Federal Aviation Administration (FAA) environmental review that could allow it to use Andersen Air Force Base, on the island of Guam in the western Pacific Ocean, as a base for launch operations.
Virgin Orbit has passed an FAA environmental review that could pave the way for the company to offer payload launchers out of the US territory of Guam in the western Pacific Ocean. Credit: Virgin Orbit
If final approval is granted – and the FAA do have reservations about Virgin Orbit being able to operate from such a remote location – the company plan to use Guam to make up to 25 air launches over a period of 5 years, possibly commencing before the end of 2021.
Following the success of the June launch, Branson noted that Virgin Orbit is to be capable of highly responsive launches from almost any point in the world. To this end, the company has already signed an agreement with Spaceport Cornwall (Newquay Airport) in the UK, and the Brazilian government has selected the company to provide launch services out of that country’s Alcântara Space Centre. These, together with Guam and their existing facilities at the Mojave Air and Space Port mean that Virgin Galactic may soon have four launch locations around the world from which it can reach a variety of orbital inclinations as required by customers.
VSS Unity drops clear of its air launcher, MSS Eve during the Unity 22 mission, ahead of engine ignition. Credit: Virgin Galactic
The down is with Virgin Galactic, the sub-orbital, tourist-focused service. Following its first successful passenger-carrying flight in July (see: Space Sunday: Unity 22 Flies), the FAA announced on September 2nd that the the sub-orbital VSS Unity is grounded, following a review of that flight, forcing a halt to the company’s operations.
The review has been triggered following an article appearing in The New Yorker magazine stating the pilots on VSS Unity ignored a warning triggered during the vehicle’s powered ascent that should have caused them to abort the flight and return the the ground. The warning indicated the vehicle was not climbing at a sufficiently steep angle to remain within it’s “entry glide cone” – the volume of space in which it can make a safe unpowered glide back to a successful runway landing at the end of the flight – during its return to Earth, and so could miss the runway entirely.
While the company has defined The New Yorker’s report as “inaccurate”, telemetry from the Unity 22 mission shows that the vehicle did exceed the limits of FAA-defined “protected airspace” for one minute and 41 seconds during the descent to landing, further justifying the FAA’s decision to order the grounding, preventing any further operations by Virgin Galactic for the next few weeks.
Virgin Galactic had been gearing-up for its next crewed flight for VSS Unity, a dedicated research flight for the Italian Air Force that would carry aloft Colonel Walter Villadei, Lt. Colonel Angelo Landolfi and aerospace engineer Pantaleone Carlucci, alongside Virgin Galactic’s chief astronaut instructor Beth Moses and pilots Michael Masucci and C.J. Sturckow when the ground of the spacecraft was announced. The mission will now not fly until the FAA concludes their review of the Unity 22 flight.
On August 28th, 2021, Astra Aerospace attempted to make the fourth launch of its Rocket 3 vehicle designed to place payloads of up to 150 kg to Sun-synchronous orbits 500 km altitude.
After two unsuccessful and one partially-successful flights of the launch system, it was hoped that this flight, carrying an instrumentation payload for the United States Space Force under the Space Test Program (and which was not designed to separate from the launch vehicle), would be a complete success.
Lift-off from Pacific Spaceport Complex – Alaska on Kodiak Island (high northern latitudes being ideal for polar orbital launches) came at 22:35 UTC, and it was immediately clear the rocket was having something of an existential moment, experimenting with moving sideways away from the launch pad, rather than upwards.
After almost 20 seconds of moving thus, the vehicle decided that “up” was perhaps the better option, and proceeded to climb into the sky, performing more-or-less perfectly through an ascent to 50 km altitude, successfully passing “max-Q” (the period when a launch vehicle experiences the maximum dynamic pressures across its frame) in the process and throttling to full power in a press for orbit.
Sadly, due to the post-lift-off incident, the vehicle had exceeded its range safety limits, risking passage over populated areas on mainland Alaska. The order with therefore given to shut down the first stage motors let it crash back into the sea.
Subsequent analysis of data suggests that one of the 5 Astra-built Delphin motors powering the rocket’s first stage failed at launch, likely resulting in off-centre thrust that caused the vehicle to strike one of its launch mounts, resulting in the sideways tilt and motion. However, despite the loss of the vehicle, the fact that it autonomously recovered to make a successful ascent to a point where, but for range safety concerns, it would likely have achieved a successful orbit, is seen as a remarkable testament to the rocket’s guidance and flight control systems.
Further launches will be pending a complete view of this flight.
Mars Updates
The Mars 2020 rover Perseverance is getting ready to make a second attempt to obtain rock samples for analysis and storage.
As I recently reported, a first attempt at sample gathering didn’t end successfully when it was discovered after-the-fact that the rock selected for the sample was made up of material too fine to be retained within the rover’s drill / sample mechanism following drilling.
Abandoning that attempt, the rover was directed to travel 455 metres to a small ridge dubbed “Citadelle”, where it will now attempt to gather a fresh sample. The area was selected as it appears to be able to withstand erosion by the Martian wind better than the surrounding ground, and has a number of interesting rock formations in it.
A look at the rock dubbed “Rochette” (image centre) at the “Citadelle” ridge that has been selected as the next target for an attempt by Perseverance to gather samples for analysis / caching. This image was captured on August 26th, 2021. Credit: NASA/JPL
In order to help ensure a sample has been collected post-drilling, a new step has been introduced into the process: once drilling has been completed, the arm and turret will be raised and positioned to allow the rover’s MastCam-Z cameras to image as a visual confirmation that there is material within it. Once confirmed, processing of the sample tube through to the rover’s on-board storage area will then be allowed.
Nor has the first “empty” tube been an entire waste – it now contains a sample of pristine Martian atmosphere, something the mission had intended to collect at some point, and so it will form a part of a sample cache of tubes the rover will at some point deposit on the surface of Mars in anticipation of collection by a future sample return mission.
While atop Citadelle, Perseverance will use its subsurface radar, called RIMFAX – the Radar Imager for Mars’ Subsurface Experiment – to peer at rock layers below it. The top of the ridge will also provide a great vantage point to look for other potential rock targets in the area.
NASA has also confirmed the next mission to Mars, due to be launched in 2024. In keeping with the agency’s approach to alternating surface missions with orbital missions, it has approved the ESCAPADE mission of twin satellites for launch in 2024.
Led by the University of Berkeley, California, the Escape and Plasma Acceleration and Dynamics Explorers mission is a relatively low-cost (under US $80 million including launch costs) attempt to put two small satellites, dubbed “Red” and “Blue” into orbit around Mars to further study the Martian atmosphere and its interactions with the solar wind.
An artist’s impression of the ESCAPADE satellites approaching Mars. Credit: NASA
The satellites will be launched using two Rocket Lab Electron rockets, with the company’s Photon satellite bus used to protect / power them during a low-energy, 11-month cruise to Mars. This marks a significant increase in Photon’s capabilities, the bus originally having been designed to support the launch of satellites into Earth or cislunar orbits. As such, the mission is seen as a “high risk” venture – but as the team behind ESCAPADE note, most missions to Mars come with a price tag of US $800 million or more, and roughly a 90-95% chance of success in reaching Mars / Mars orbit. ESCAPADE is estimated as having an 80% chance of success in doing the same – but at one-tenth the cost, thus making the increased risk in using Rocket Lab systems worth the effort.
Once in orbit, the mission will collect data that could help reconstruct the climate history of Mars and determine how and when it lost its atmosphere. ESCAPADE also will study the ionosphere of Mars, which can interfere with radio communications on the surface and between Earth and Mars colonists. Finally, with simultaneous two-point observations of the solar wind and Mars’s ionosphere and magnetosphere, ESCAPADE will provide a “stereo” picture of this highly dynamic plasma environment in the planet’s upper atmosphere.
And when it comes to human missions to Mars, a new study from the University of California Los Angeles proposes a novel way of reducing the impact of radiation during the journey to / from Mars: by launching during periods of high solar activity, notably the periods immediately following that of solar maximum, when the Sun is at its most active. While launching missions during periods of high solar radiation to reduce the risk of radiation exposure might sound counter-intuitive, there is some logical to the idea.
Simply put, interplanetary missions face two radiation risks – solar, which can be reasonably well mitigated against in a variety of ways (but not entirely avoided or made “safe”) and galactic cosmic rays (GCRs), which are considerably harder to deal with, and more devastating in their impact. However, during periods of high solar activity, the more energetic solar radiation actually deflects GCRs away from the solar system. So the UCLA study suggests that by launching crewed missions in the years immediately following a period of solar maximum could massively reduce exposure to GCRs without significantly increasing the risk from solar radiation.
Just how practical it would be to restrict missions to Mars to certain time frames within the Sun’s 11-year cycle is debatable. If we are to practically explore and possibly establish a permanent presence on Mars, missions will need to be a lot more frequent; so more practical research into things like garment materials, materials used in space vehicle design, etc., that could help mitigate both primary and secondary radiation would likely be far more practical. However, the bright spot in the UCLA study does suggest that if missions are kept to below 4 years duration, then radiation exposure could be seen as “acceptable” – and currently, the more favoured “opposition” class of mission of 2.5 to 3 years duration falls inside that limit.
A view across Gale Crater from “Mount Sharp”, captured by the Mastcam on NASA’s Curiosity rover on July 3rd, 2021, Sol 3,167 for the mission). The dark band of rippled material in the middle-ground of the image is a dune field of volcanic sand. Credit: NASA/JPL
It’s now nine years since NASA’s Mars Science Laboratory rover Curiosity arrived on the Red Planet. To celebrate, the rover is about to enter a new phase of exploration as it continues to climb the slopes of “Mount Sharp” (more correctly, Aeolis Mons), the 5 km high mound that rises from the centre of Gale Crater.
Through July and August, the rover has been passing through a “transitional field” between a region on the mound that is dominated by the presence of clay minerals and one dominated by sulphates. While doubt has recently be cast on how large a role water has played in the crater’s (and particular “Mount Sharp’s”) formation, the change from clay minerals to sulphates is nevertheless important, as it marks a point where very different processes were at work on Mars as a result of the planet’s changing climate.
The rocks here will begin to tell us how this once-wet planet changed into the dry Mars of today, and how long habitable environments persisted even after that happened.
– Abigail Fraeman, MSL deputy project scientist
This is an area the MSL science team have been anxious to reach; roughly 460 metres above the crater floor where the rover landed in August 2012, it has been a target for Curiosity since before the rover arrived on Mars, as it could hold the key to the impact of climate change elsewhere on Mars where it is thought water may once have been present.
The transition between environments comes as Curiosity celebrates nine years of operations on Mars. To mark this NASA recently released a video of images captured by the rover during July, as it approached the transitional area. Because it is currently winter within Gale Crater, a time when the amount of dust in the tenuous Martian atmosphere is especially low, the images used in the video are exceptional clear and detailed images that even reveal the crater walls in detail, even though they are over 70 km away.
Another rover with cause to celebrate is China’s Zhurong rover, currently operating on Utopia Planitia. Somewhat smaller than the NASA rover, Zhurong arrived on Mars at the start of an initial 90-sol (92 day)mission are a part of China’s TIanwen 1 interplanetary mission. Since its arrival, the rover has been moving south from its lander vehicle, carrying out a range of science operations.
China has perhaps not been as pro-active as NASA in their social media output on the mission, but Zhurong has performed exceptional well, returning some 10 gigabytes of data to mission control on Earth whilst travelling almost a kilometre, visiting other elements of the mission along the way, such and the backshell and parachute that protected it through entry into the the Martian atmosphere and helped to decelerate in its descent ready for landing. So well, in fact that the China National Space Administration (CNSA) has announced the mission is to be extended through a second 90-sol period.
The rover has most recently reached an area believed to have once been the shoreline of ancient coastal waters in the region, marking it as a particular area of scientific interest. In particular, the rover is being directed to drive to a feature described as a “groove” just over 1.6 km from its current position.
Hopefully, by providing data on this area for our scientists, we can get a deeper understanding of the geology of Mars, and then even see if we can find evidence of the existence of an ancient ocean in Utopia Planitia. If it is possible for us to see from the top to the bottom [of the groove], or if there are disparities of rock types and compositions, we could learn about what has happened in its geological history. So, this is what we’re going to focus on in the near future
– Liu Jianjun, chief designer of the Tianwen 1 ground application system
A recent image release by CNSA via CCTV (China state television) show the view make along Zhurong’s route south, captured by the rover’s black and white navigation cameras. Credit: CNA / CCTV
Meanwhile, in Jezero Crater, NASA’s ingenuity Mars helicopter drone has completed its 12th – and most challenging – flight.
On August 16th, 2021, the helicopter took off on a reconnaissance flight again in support of the Mars 2020 rover Perseverance. The flight was one of the longest to date, with Ingenuity covering over 450 metres and lasted 169 seconds over terrain, dubbed “Séítah South”, regarded as “risky” due to its varied nature.
Flying over Séítah South carries substantial risk because of the varied terrain. When we choose to accept the risks associated with such a flight, it is because of the correspondingly high rewards. Knowing that we have the opportunity to help the Perseverance team with science planning by providing unique aerial footage is all the motivation needed.
– From the Ingenuity flight log
The flight saw the helicopter return to the “round trip” approach seen in initial flights, travelling out over a region where, if it had been forced to make an emergency landing, could have resulted in it suffering damage or loss, and then back again. The route was selected so as to allow Ingenuity recorded the terrain in sufficient stereoscopic detail that mission planners might determine a route into the terrain for Perseverance. and have the rover drive itself safely to specific points of interest.
Taking the rover into “Séítah South” is regarded as riskier than flying Ingenuity over it, but the region is also full of intriguing rocks that the science team believe the risk is worth the potential returns.
During the 12th flight of NASA’s Ingenuity helicopter, the craft overflew an area of rough terrain called “Séítah South”, and while manoeuvring, the helicopter managed to capture an image of the Mars 2020 rover Perseverance from a distance of around 1/2 a kilometre, NASA later released this enlarged image of the rover as seen by Ingenuity. Credit: NASA/JPL
Currently, Mars is approaching a period of solar conjunction – meaning it is on the far side of the Sun relative to Earth, and about to pass “behind” the Sun as seen from Earth, and event that happens once every two years. During this period, and the time leading up to it an immediately after it, ionized gas radiating out from the Sun’s corona can interfere with radio signals between Earth and vehicles operating on the surface of Mars or in orbit around it, increasing the risk of miscommunications and possible damage to, or loss off, those vehicles.
To avoid this, the fleet of spacecraft currently in orbit around Mars from the USA, UAE, Europe and China will be order to enter “safe” modes during the first two weeks of October, shutting down all major operations until such time as communications can be safely resumed. At the same time, the rovers active on the surface of Mars will switch to autonomous modes of operation, reducing their science operations until such time and full communication between them and the orbits spacecraft and the spacecraft and Earth can be re-established.
Things have been getting a little rocky – pardon the pun – for the US rover missions on Mars of late.
On August 5th (Sol 164 for the mission) the Mars 2020 mission had been expected to recover its first sample from within Jezero Crater, some of which would be subject to analysis and the rest held for future deposit on the surface of Mars to be retrieved by a future NASA / ESA sample-return mission.
All seemed to go well with the operation – Perseverance deployed its robot arm and used the drill to cut some 7cm into the selected target rock, dubbed “Paver Rock”, a part of the “Crater Floor Fractured Rough” region of the crater floor. However, data received by mission managers after the drilling operation have been completed revealed the tube to be empty.
Gathering samples with Perseverance is a lot more complicated that with Curiosity. In particular, rather than the drill gathering a sample within itself, it is designed to hold a sample tube, which has to be delivered into the bit, and then removed from it and transferred into the rover’s body. Following the drilling operation, part of the process involves extending a probe into the sample tube to confirm it contains material – and it was lack of any return from this probe that alerted the mission time that the sample attempt may have failed.
This enhanced-colour image from the Mastcam-Z instrument aboard NASA’s Perseverance rover shows sample tube inside the coring bit after the Aug. 6 coring activity was completed. The bronze-coloured outer-ring is the coring bit. The lighter-coloured inner-ring is the open end of the sample tube. Credits: NASA/JPL
The lack of data lead to checks on the sample gathering systems, and a detailed examination of the bore hole and the detritus around it using two of the other instruments on the turret – SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) and Watson (Wide Angle Topographic Sensor for Operations and eNgineering). These examinations revealed something unexpected and a first for sample gathering operations on Mars.
In short, SHERLOC and WATSON revealed that as the drill bit cut into the rock, it produced a powder so fine, it could not be held within the the sample tube inside the drill bit, and as the bit was withdrawn the gathered material simply fell back out, joining excess material within the hole and the detritus surrounding it.
As a result, the mission team have opted not to make a second attempt at sample gathering with the current target rock. Instead, the rover is to be directed on to its next target, a rock formation in the “South Seitah” region of Jezero Crater, which it will reach in early September.
This image taken by NASA’s Perseverance rover on Aug. 6th, 2021, shows the hole drilled in a Martian rock as a part of the rover’s first attempt to collect a sample. It was taken by one of the rover’s hazard cameras. Credit: NASA/JPL
Meanwhile, half a world away, Curiosity is celebrating the ninth anniversary of its arrival on Mars. The first of NASA’s nuclear-powered Mars, Curiosity has been continuing its journey of discovery within Gale Crater, although some of the findings made as a result of the data gathered have recently been subject to new evaluation by the University of Hong Kong, leading to some interesting conclusions.
In has long been presumed that the major factor in the formation of Gale crater’s landforms has been water in the form of a series of shallow lakes that laid down sedimentary clays and similar over time, with wind playing a much later role in things, such as sculpting “Mount Sharp”, the large mound at the centre of the crater – and discoveries made by the rover throughout its sojourn through the crater and up “Mount Sharp” have tended to support this view. However, the UHK study suggests that the roles may have been reversed – that while the crater was once the home of water, the dominant factor in the development of the landscape within the crater was in fact the wind.
A view across Gale Crater, as captured by the Mastcam system on NASA’s MSL rover Curiosity
The conclusion was reached after an extensive study of Curiosity’s findings in the search for elements considered “mobile” – which are indicative of water being present in their deposit, and elements that are “immobile”, which are not water soluble, and which are generally formed in dry regions, where winds play a significant role. The UHK study, led by Dr. Jiacheng Liu suggests that immobile elements exist in much higher concentrations at high levels in the rock than would be the case if water had been present during their formation.
This doesn’t mean the crater was never the home of a lake; rather, Dr. Lui suggest that Curiosity has been studying overlays much of the evidence for the ancient lakes, and was largely form by wind action depositing layers of material over time, which were then compressed into layer and then further sculpted by the wind, rather than water-based sedimentation later sculpted by winds. He also suggests that the “mobile” elements the rover has found may not be the result of water-base depositing within the crater, but were rather created elsewhere on Mars, and again carried into the crater by windows a dust storms.
If correct, this is important because while it does challenge the idea that water did play a role early in the history of Gale Crater, it does tend to confirm the idea wind and atmosphere played an equally important role in its history, which in turn always for a more varied picture of the geological history of the surface of Mars to be built up, one potentially far more diverse and active then previously believed. to be the case.
Boeing Returns Starliner to Factory for Fixes
Boeing’s CST-100 Starliner, designed to transport crews to and from the International Space Station (ISS) from US soil, now looks like it wouldn’t be able to complete its second test flight until 2022.
The flight – called OFT-2 for “orbital flight test 2” had been due to lift-off on August 3rd. However, as I reported last time around, the launch was postponed after it was discovered valves designed to control the vehicle’s thruster system has all fused in their “closed” position, resulting in the launch attempt being cancelled and the orbiter and its Atlas 5 being rolled back to the Vertical Integration Facility at Cape Canaveral Space Force Station, where Boeing hoped to effect repairs.
Boeing technicians attempt to repair valves in the propulsion system on the CST-100 Starliner in the Vertical Integration Facility at Cape Canaveral Space Force Station. The valve issues have now forced an extended delay to the vehicle’s OFT-2 mission. Credit: Boeing
While 9 of the 13 valves were fixed, four remained stuck, and it was discovered the cause of the problem appeared to be nitrogen tetroxide (NTO), used as thruster propellant, permeating Teflon seals in the valves to react with moisture, creating nitric acid that fused the valves shut. This, and the four remaining stuck valves prompted Boeing to announce that the capsule would be returned to their facilities where a more extensive review of the situation can be carried out, both to repair the remaining valves and determine why the NTO permeated the valve seals – something not seen in testing, and hoe moisture accessed the valves.
It is not clear how long this review will take, or whether it will require further changes to be made to the flight test vehicle to prevent any recurrence. However, the launch schedule at Canaveral Space Force Station means there a very few slots into which a further attempt at launch could be slipped before the end of the year, and Boeing have been talking in the review taking “several months” to complete.
Rocky NASA / Roscosomos Relations Continue
In 2018, the IISS suffered a small-scale loss of pressure. It was not the first such event, and it never put the crew at risk. However, investigations into the cause eventually uncovered a small hole in the skin of the orbital compartment of Soyuz MS-09 crew vehicle docked at the station. This hole was subsequently repaired by the cosmonauts on the ISS, and the vehicle ultimately made a successful return to Earth.
The cause of the hole – around 2mm across – has never been fully explained, although it seemed to many it was likely the result of a error being made during the vehicle’s assembly. However, not long after the situation, Roscosmos head Dmitry Rogozin started to point fingers, suggesting the hole was the result of attempted sabotage by one of the non-Russian crew then aboard the ISS. This claim has now resurfaced.
Dr. Serena Auñón-Chancellor – accused by a “High ranking official” at Roscosmos of attempting to sabotage Soyuz HS-09 in 2018, the accusation seen as a means of deflecting attention away from criticism of the recent “Nauka incident”. Credit: NASA
On Thursday, August 12th, Tass published an article quoting a “high ranking official” at Roscosmos – possibly Rogozin himself – that the hole on MS-09 was the result of attempted sabotage – and the report pointed a finger at the only woman on the crew at that time: NASA astronaut Dr. Serena Auñón-Chancellor, who was serving as the Expedition 56 Flight Engineer.
To give credence to the claim, the report breaks with a long-standing NASA protocol of not commenting on astronaut health issues by revealing that on her return to Earth, Dr. Auñón-Chancellor had to be treated for a blood clot in a vein in her neck; the insinuation here being that the condition caused her to have a breakdown whilst on the station, resulting in her sabotaging the Soyuz in order to force a return to Earth. Auñón-Chancellor has denied the claim, and has been joined by NASA senior management from Administrator Bill Neilson on down in rebutting the Tass report.
Serena is an extremely well-respected crew member who has served her country and made invaluable contributions to the agency, and I stand behind Serena — we all stand behind Serena and her professional conduct and I did not find this accusation credible.
Kathy Lueders, NASA Associate Administrator, Human Exploration and Operations Mission Directorate.
Soyuz MS-09 docked with the ISS in 2018. The hole piercing the hull lay within the circular orbital module / airlock, circled. Credit: NASA
Overall, the accusation would appear to be a retaliation for continued criticism over the recent “Nauka incident”, which a newly-docked Russian module at the station fire its thrusters to push the station into a slow rotation that took some time to correct (see here and here for more), and likely the result of a failure on the part of Russian ground controllers to correctly “safe” the module’s propulsion systems.
However, whether intended as a deflection or not, the the article stands in stark contrast to recent US claims that the Russian / American space partnership is healthy. And if the comments did come from Rogozin, they will be the latest in a series of remarks he has made in his two tenures in leading Roscosmos that appear to be intentionally aimed at straining US / Russian relations.
In 2014, Rogozin threatened an end to Russian cooperation on the ISS as a result of annoyance with US management of the station, and in 2020, he summarily rejected an invitation by America for Russia to join the Artemis programme, indicating Russia would rather work in partnership with China. More recently, he has suggested that Russia could abandon the ISS altogether after 2024, and instead concentrate on a new space station – and that as part of this, Roscosmos might repurpose one of the modules they are fabricating for the ISS to form the core of their new station, allowing it to commence operations “by 2030”.
NASA Lunar Spacesuits “Won’t be Ready” for 2024
The Exploration Extravehicular Mobility Unit (xEMU) spacesuits that NASA astronauts will need to walk on the Moon won’t be ready form operational use until 2025, further ending any idea of a US return to the Moon by the end of 2024.
The new suit has been in development since 2007, but has encountered a number of design challenges over the years, as well as encountering technical and funding issues. To date, just over one-third of the funds needed to develop the suit have been awarded to NASA, and in 2020 it had to undergo a complete redesign in order to remove a further 10 K from its overall mass.
A mock-up of the Exploration Extravehicular Mobility Unit (xEMU) lunar spacesuit being revealed in 2019. The actual suits won’t be ready for use on a lunar landing mission until 2025. Credit: NASA/Joel Kowsky
With the impact of the CIVID pandemic also impacting work on the suit, the NASA IG reports that in practical terms the suit cannot be ready for lunar use until early-to-mid 2025.
And the suit isn’t the only element of the Artemis programme unlikely to meet the 2024 deadline; as reported in these pages, it is highly unlikely the Human Landing System (HLS), the vehicle that will deliver crews to the surface on the Moon and return them to orbit, will be ready within the next three years, whilst the Space Launch System – required to launch crew-carrying Orion vehicles to the Moon – is seeing its test flights slip back in their project time frames.
SpaceX Boca Chica: A giant crane gets ready to lift Starship S20 some 90 metres into the air so it can be stacked onto Super Heavy Booster 4, Friday, August 6th. Credit: BocaChicaGal / NASASpaceflight.com
SpaceX has been stepping up the pace of work at its Boca Chica Starbase facility, home of the Starship and Super Heavy booster development programme, in recent weeks.
Towards the end of July, the company started transferring personnel from its headquarters in Hawthorne, California to Starbase in what was seen as a start of gearing-up for flight activities out of Boca Chica. This operation came alongside continuing construction work at Starbase and the initial testing of the prototype B3 Super Heavy booster, which included a static-fire test of three Raptor sea-level engines. Since then, the pace of developments at Boca Chica has been dramatic – particularly in the last week and a half.
Two shots of the 70-metre tall Booster 4 departing the SpaceX high bay on its way to the launch facilities. Note the fixed (non-folding) grid fins that will be used to steer operational Super Heavy boosters to back to Earth, and in the background of the picture on the left, the lower tank section of starship S20. Credit: Elon Musk
In that time, the first flight-capable Super Heavy booster was moved down to the launch facilities, whilst Starship 20 (SpaceX has dropped the “SN” designation), the vehicle that will sly with it in an attempt to reach orbit later this year, completed its major assembly, stacking the two cylindrical tank sections one atop the other an onto the vehicle’s engine skirt, and then adding the upper ring sections and nose cone.
This work included the installation of two of the news aft aerodynamic fins that are around 20% smaller than those used on earlier test vehicles, offering a reduction in mass, and the installation of six Raptor motors – 3 sea-level engines (believed to be the three motors used in the Booster 3 static fire test) and three fixed vacuum engines – although all six may have only been installed for testing purposes.
Starship 20 departs the Starbase production area en route to the launch facilities, GSE tank 3 following behind, destined for the fuel farm. Credit: BocaChicaGal / NASASpaceflight.com
At the same time, the massive 370-tonne launch table – the ring of hydraulic clamps, actuators, bolt mounts, etc., that will hold a booster/starship combination securely on the launch pad, was hoisted up on to the ring of the launch platform’s legs and installed. This paved the way for the 70-metre tall, 9-metre wide Booster 4, complete with a contingent of 29 Raptor motors – 20 fixed in a ring around the rocket’s circumference, and 9 centre motors that can be gimballed to provide directional thrust – to be hoisted up onto the launch platform and secured into the launch table.
Then, on Thursday, August 5th, in a move that almost caught people off-guard, SpaceX proceeded to roll-out Starship 20 from the production site and transport it to the launch facilities.
The base of Booster 4 showing the central cluster of 9 Raptor engines and the outer ring of 20. Credit: SpaceX
This prompted a lot of speculation amongst starship fans that the launch could be coming in days – something that just wasn’t going to be the case. The fact that the vehicle lacked a full complement of heat shield tiles, the launch facilities aren’t complete, nor is the consumable feed feed, and so on, all make it clear the system is still months from any launch. Plus, the FAA environment assessment hasn’t been completed, so SpaceX don’t have federal clearance to attempt an orbital launch.
Apparently, there had been plans to use cranes to perform a “test stacking” of S20 in top of B4, but these were scrapped for the day due strong wind gusts. Instead, attention turned to mounting the aforementioned missing heat shield tiles to S20.
The Starbase orbital facilities: to the top right: the orbital launch platform and support tower with Booster 4 and Starship S20 waiting to be lifted. Top lift, , the tank farm with the newly-delivered GSE 3 tank awaiting its turn to be lifted into place. Credit: RGV Aerial PhotographyHowever, on Friday, August 6th, S20 was raised some 95 metres into the air and then gently lowered onto the reinforced interconnect at the top of the Super Heavy. In doing so, the two vehicles became the largest launch system ever raised – 120 metres tall from engine bells to tip of the nose cone (that’s around 10ft shy of 400 ft). With the launch table taken into account, the stack of vehicles rose some 140 metres above the ground.
Work on the stack then paused while, close by, GSE tank 3 was also hoisted aloft and moved into position on its mounting ring at the tank farm, where it will later be sheathed by a grey cryogenic cooling sleeve. With this work done, the massive “Frankencrane” that has been assembling the launch support tower, once more lifted S20 aloft and then lowered it back onto its autonomous transport so it could be rolled back to the production facilities to undergo further work.
Starliner: No Go for Launch
The long-awaited launch of the Boeing CST-100 Starliner vehicle on its uncrewed second Orbital Flight Test (OFT-2) has been indefinitely delayed n a further blow to the troubled programme.
Scheduled to lift-off on Tuesday, August 3rd, the launch was scrubbed after the Boeing launch team received warning of “unexpected valve position indications” within the capsule’s propulsion system. Initially, it had been hoped that a further attempt could be made on Wednesday, August 4th. However, Further checks on the vehicle, Boeing announced a suspension of all launch attempts, and that the vehicle would be rolled back to its service structure to allow further checks to be made on the vehicle.
The OFT-2 Starliner capsule on its Atlas 5 booster prior to the mission being indefinitely postponed. Credit: NASA/Aubrey Gemignani
Designed to partner the SpaceX Crew Dragon – already operational – in ferrying crews to and from the International Space Station (ISS), Starliner first flew on an uncrewed mission in December 2019 in what was supposed to be a final check-out prior to commencing crewed operations. However shortly after the vehicle reached orbit it suffered a software glitch that caused repeated incorrect firings of its manoeuvring motors, leaving it with insufficient fuel to make a rendezvous and docking with the ISS. Hence the need for the OFT-2 flight.
That this has now been postponed following 18 months of reviews and changes to both systems on the vehicle and the procedures used in readying it for flight, is nothing short of embarrassing for Boeing and NASA alike – the CST-100 contract being the most expensive in the Commercial Crew Programme.
Inara Pey: Living in a Modemworld 