Space Sunday: Starliner, “dog doors” + more SpinLaunch & China

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The CST-100 Starliner sits just 10 metres off the ISS, its nose open to expose its docking mechanism and forted port May 20th, 2022. Credit: NASA

Boeing’s CST-100 Starliner finally lifted-off from Space Launch Complex 41 at the Cape Canaveral Sport Force station on Thursday, May 19th, sitting atop a United Launch Alliance (ULA) Atlas 5 booster, in what is a critical test flight for the system, one that involves a rendezvous and docking with the International Space Station (ISS).

Called Orbital Flight Test 2 (OFT-2), the uncrewed mission is the second attempt to fly a Starliner vehicle to a successful docking with ISS – seen as a critical precursor to Starliner vehicles carrying crews to / from the ISS. The first attempt, carried out in December 2019 failed to rendezvous with the ISS after a software issue caused the vehicle’s orbital manoeuvring and attitude control (OMAC) thrusters to misfire repeatedly, leaving the vehicle with insufficient propellant reserve to make the rendezvous once the issue had been controlled. However, the Starliner – christened Calypso, and now earmarked for the first CST-100 crewed flight – still completed the orbital tests for the mission successfully, and made a safe return to Earth.

CST-100 OFT-2 lifts-off from SLC-41 at Cape Canaveral Space Force station, May 19th, 2021. Credit: NASA

Following lift-off at 22:54 UTC, on May 19th, the Starliner vehicle (currently unnamed) reached an initial orbit successfully. However, at 31 minutes after launch, things went slightly awry. At this point one of the vehicles 12 main OMAC thrusters was due to fire for 45 seconds to place the Starliner on the correct trajectory to commence its “chase” to the space station.

However, one second after firing, the thruster shut down. This triggered an automatic firing of a second thruster, which ran for 25 seconds before shutting down, leaving a third thruster completing the burn. Whilst of concern, the initial two thruster failures were not sufficient to prevent the mission continuing, and both NASA and Boeing are reviewing data to determine what the problem is – and whether the two faulty thrusters are still capable of firing correctly – the main OMAC thrusters being needed to de-orbit the vehicle at the end of its flight.

Sunlight flashes off of the hull of the CST-100 Starliner as it chases the ISS. Credit: NASA

Despite these teething problems, the Starliner “caught up” with the ISS on Friday, May 20th, having successful completed a series of tests whilst closing on the ISS. At 20:36 on the 20th, the crew on the ISS caught their first sight of the Starliner. The capsule steadily closed on the station before completing two “flyarounds”, allowing the ISS crew to observe the vehicle’s overall condition ahead of docking.

Utilising self guidance, the capsule then closed to within 180 metres of the space station before coming to a stop and then moving away once more in an “approach and retreat manoeuvre” intended to test the vehicle’s ability to carry out precise manoeuvres in close proximity to the station. After this, it resumed its approach towards the Harmony module and its docking port, coming to within 10 metres of the station when it was ordered to stop when mission control confirmed it was a little off-centre relative to the docking port.

Another view of the Starliner approaching the Harmony module of the ISS, May 20th, 2022. Credit: NASA

This eventually required the vehicle to back away from the station, correct its alignment and make a second approach – which was again halted at 10 metres from the station. This proved to be the start of an irritating period of minor issues with the docking mechanism at the front of the vehicle which ultimately delayed docking by 90 minutes, Starliner finally connecting with the ISS at  00:28 GMT on Saturday, May 21st.

Following docking, a further series of testes on the vehicle were conducted, and the hatches between station and capsule were finally opened at 16:04 GMT, allowing astronauts Robert Hines and Kjell Lindgren connect ventilation systems and move camera systems into the capsule. They also greeted the capsule’s main occupant: Rosie the Rocketeer, a mannequin occupying the commander’s seat in the capsule and equipped with various instruments to test how orbital ascent (and return to Earth) affect those riding in the vehicle.

The Starliner docked against the extended docking arm of the Harmony module – the latter retracts to pull the capsule against the docking port. Credit: NASA
Also on the flight is a plush toy of Jebediah Kerman, one of the four original characters from the space game Kerbal Space. The first Kerbal to officially make it to space, “Jeb” is the mission’s “zero-g indicator” for the flight. His presence was kept secret by the ground control team, so that he might be discovered by the ISS crew on entering the vehicle – Kerbal Space is apparently very popular among Boeing and NASA staff.

The Starliner is set to remain docked with ISS for 4-5 days before departing for a return to Earth.  If declared a success post-analysis, OFT-2 should pave the way for the first crewed flight before the end of 2022. Called Crewed Flight Test, it will carry a crew of 3 (personnel still to be confirmed) to the ISS on a 10-day (ish) mission to the space station. That in turn should clear the way for operational flights with Starliner to start in early 2023.

Curiosity’s “Dog Door” and InSight’s Demise

Parts of the Internet have been all agog over the last few days, after NASA Tweeted images on May 18th captured by the Mars Science Laboratory rover Curiosity, labelled (perhaps a little unfortunately) as a “door shaped fracture” that offers (again, unfortunate wording) “a doorway into the ancient past” – terms that were taken just a little too literally by some.

A mosaic of 113 images captured by the MastCam system on NASA’s Curiosity rover captures the face of “East Cliff” on May 7th, 2022, (mission sol 3,466). The fissure of “Dog Door can be seen over to the upper left. This mosaic has been colour and light adjusted to give the same conditions as if the feature was being viewed on Earth. Credit: NASA/JPL

The images were part of a series captured by the rover on May 7th, during a survey of a sedimentary mound of rock layers dubbed “East Cliff”, and sitting on the flank of “Mount Sharp”, the 5-km high mound of material at the centre of Gale Crater. During the processing of 133 images taken of “East Cliff” using the rover’s MastCam, the science team noted an interesting fissure within the upper, most weathered layers of the mound.

Looking to be rectangular in shape, the fissure does appear to be door-like – although not one any human is going to be walking through, given it is just 29.1 cm tall and the maximum width of the feature in just 38.9cm (sizes which prompted NASA to call the feature a “dog door” as it is closer in dimensions to the front opening on a kennel).

A further mosaic from Curiosity taken on May 7th, 2022, showing the “Dog Door” fissure more centred (and circled) in the image. Again, the image has been colour / light adjusted for Earth lighting. Credit: NASA/JPL

However, while the fissure is real, it’s door-like appearance is the result of two key factors: the angle at which sunlight is striking the mound, which casts the back of the fissure into shadow, giving the impression it is some form of entrance; and the also pareidolia – the tendency for the human brain to try and interpret strange sights and objects by trying to perceive them as something familiar – in this case a door.

Such fissures are not actually uncommon within geological features like East Cliff, both here on Earth and on Mars. They are caused by the intersection of multiple vertical (from weathering under the influence of water / wind) with horizontal layering of rock such that the most exposed part of the result lattice break away, forming a shallow fissure with regular-looking sides.

An anaglyph close-up of the “Dog Door” with annotations indicating the approximate width, height, and depth of the open fissure. Credit: NASA/JPL

And the comment about being a “doorway into the past”? That’s simply a reference to the fact that the collapse that formed the fissure offers the opportunity to perhaps examine rocks that haven’t been so exposed to the ambient surface conditions of Mars and may have had a degree of protection from harsher solar radiation, and so might reveal further chemical / mineral clues to the ancient past of “Mount Sharp”.

It has also been announced that NASA’s InSight Lander mission, which has been operating on Mars since November 2018, but which tends to get overlooked in favour of the “sexier” rover missions, may be coming to an end as soon as mid-July 2022.

InSight, which I covered in-depth at its May 2018 launch (see: Space Sunday: insight on InSight, May 2018) has been carrying out studies into the interior of Mars, including the study of “Marquakes” that appear to take place deep within the planet. However, it has been suffering from a significant decrease in available power as a result of dust accumulation on the pair of 2.2 metre diameter solar arrays.

Comparative images showing how dust accumulated on InSight’s sollar arrays. On the left, one of the arrays 10 days after landing, looking fairly clean. On the right, the same array after just under 4 months on Mars. Credit: NASA/JPL

As I reported in 2021, such was the dust build up on the arrays, the electrical power generation on the lander has been reduced to just one-tenth of the 4.6 kilowatt-hours the arrays generated during the initial days of Mars operations, and is now insufficient to continue to meet the needs of all systems on the lander.

Because of this, the decision has been taken to start powering-down non-essential systems and instruments, the intention to leave only the seismometer positions on the surface of Mars working, together with the camera system mounted on the lander’s robot arm (which will be oriented to focus on the seismometer before the arm is shut down), and the lander’s communication system.

However, even with the reduction in power usage this will achieve, the mission team believe that power production levels will drop below the minimum required to keep the seismometer functioning by mid-to-late July; although sufficient power will still be generated to power the communications system through until possibly the end of 2022.

Despite being overlooked at times, InSight has far surpassed its planned 2-year primary mission, and has yielded a lot of information about the processes at work deep within Mars.

SpinLaunch Update

In November 2021, I wrote about Spinlaunch, a company that plans to use a 100-metre diameter vacuum accelerator to propel payloads of up to 200 kg on the first leg of their journey to orbit.

This would be achieved by placing the payloads and their rocket inside a ballistic projectile (total mass: 11.2 tonnes) which would then be spun-up to a speed of 8,000 km/h with the drum-like accelerator before releasing it along a guidance tube (think gun barrel) and out into the atmosphere to be hurtled to a altitude of 61 km, where the projectile splits open to release the rocket, which can ignite its motors and power its way to orbit.

The Spinlaunch prototype accelerator shown in scale to the statue of liberty. Credit: SpinLaunch
This may sound crazy – and there are a lot of issues / questions around the full-size implementation of the system – however, since October 2021, SpinLaunch has been carrying out increasingly ambitious sub-orbital tests using a 1/3rd scale accelerator operating at 20% of the full-scale system to launch projectiles (“simulators”) on ballistic flights to offer both a proof of concept for the idea and to gather essential data on its overall feasibility.

As a part of these tests, on April 22nd, 2022, Spinlaunch for the first time carried out a test launch of a simulator equipped with a camera system. The resultant video is impressive, showing the launch accelerator dwindling in size below the projectile as it climbs into the atmosphere at 1,600 km/h before starting its tumble back to Earth, where the video cuts out.

However, before watching the video be warned: a longitudinal spin is imparted to the simulator to help with stabilising it in flight (again akin to a bullet being stabilised by the rifling in a gun barrel), and this spinning might induce a sense of motion sickness in the sensitive.

The exact height reached by the projectile simulator has not been confirmed by SpinLaunch, but given the curve of the Earth can be seen, it would seem likely that the simulator reached several kilometres in attitude.

There is still a long way to go before SpinLaunch is close to being ready to start full-scale operations (and much to be proved before they do), but such has been their progress to date, NASA has signed-on to the project with the intent to fly at least one payload of their own on a sub-orbital launch so that they might gather data on system and payload performance.

More from China

May has been a busy month for announcements by China concerning its space ambitions. In the previous Space Sunday update, I covered the most recent news on China’s upcoming space telescope. It is just one of three initiatives to gain update / confirmation.

The first part of May saw a series of television interviews with CCTV, the state television network, Huang Zhen the chief designer at the China National Space Administration (CNSA) gave the first official confirmation of the multi-facetted work being put into developing a permanent human presence on the Moon.

In particular, the interviews gave the first official confirmation of China’s Manned Lunar Deep Space Exploration Project Office (MLDSEP), tasked with developing the technologies required to establish a permanent presence on the Moon – and to enhance those technologies, where relevant, for future crewed mission to Mars.

The interviews also touched upon – if only superficially – various aspects of the work MLDSEP is engaged upon. These include: the development of Earth-based training facilities for lunar hardware and operations; design and development on lunar hardware including: crewed lander vehicles, pressurised rover vehicles, payload landers, and what appears to be a lunar orbital space station similar in nature to NASA’s Gateway station, together with research into and research into in-situ resource utilisation capabilities to provide air, water, and building materials to support an expanding lunar presence.

A general graphic displayed by China state television during interviews with CNSA chief designer Huang Zhen, showing some of the lunar hardware CNSA are developing for human operations on the Moon. Credit: CNSA / CCTV

Then, on May 13th, another of China’s chief designers – Zhang Rongqiao, responsible for China’s highly successful Mars orbiter / lander / rover mission, Tianwen 1 – confirmed his team are deep into developing Tianwen-2, a decade-long two-phase, mission of enormous ambition.

The first phase of the mission, lasting 2 years, will see the vehicle launches and rendezvous  with asteroid 469219 Kamo’oalewa, a quasi-satellite of Earth occupying a solar orbit close to our own..On arrival, Tianwen-2 will first perform a “touch and go” flyby similar to those used by Japan’s Hayabusa 2 and NASA’s OSIRIS-Rex, to gather samples from the surface of the asteroid.

Assuming a suitable location can be found; the vehicle will then attempt to anchor itself to the asteroid using a set of robot arms, and then drill into the asteroid to obtain a core sample. Tianwen-2 will then return to Earth and use the planet’s gravity to slingshot it on its way to its next target, but not before it has dropped off the samples from 469219 Kamo’oalewa for recovery and study.

The slingshot manoeuvre will set the vehicle on a 7-year journey to 311P/PanSTARRS, a so-called “active asteroid”, because it has properties seen within both asteroids and comets. Once there, it will orbit and analyse the asteroid for at least a year (possibly longer, depending on propellant reserves) using a range of cameras and spectrometers to glean insights into questions such as the mystery of the source of Earth’s water. Data gathered will be communicated back to Earth, although Tianwen-2 will not itself be returning. No images have been released as yet to show the proposed design of Tianwen-2.

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