Space Sunday: Ax-1 Artemis, ESA & a galaxy far, far, away

Crew Dragon Endeavour docked with the forward port on the US Harmony module at the ISS, and bearing the Axiom logo. Credit: NASA

The first entirely private sector mission to the International Space Station (ISS) lifted-off from the SpaceX Falcon launch facilities at Pad 39A, Kennedy Space Centre (KSC) on Friday April 8th, 2022, carrying a crew of four to the station aboard the Crew Dragon vehicle Endeavour.

The launch took place at 16:17 UTC, with the Falcon 9’s first stage making a flawless ascent prior to upper stage separation, then completing a boost-back manoeuvre and a successful return to Earth to land on one of the SpaceX autonomous drone ships. It marked the 5th successful flight for the core stage, which coincidentally was the same stage that launched the first all-private mission to Earth orbit – Inspiration4 (see: Space Sunday: Inspiration4 and Chinese flights) in September 2021.

Ax-1 has been seen by some as just another jolly jaunt into space by those who can afford it; however and in fairness, it is slightly more than that. Axiom Space was founded to create the world’s first commercial space station. While others have since entered this arena, Axiom has been granted access to the forward port of the ISS’ Harmony module, to which Axiom plans to dock the Axiom Orbital Segment; a complex that could grow to five pressurised modules after 2024.

Axiom’s plans for their space station (click for full size). Credit; Axiom Space

In order to help finance their plans, Axiom plan to offer a series of fare-paying flights to the ISS, with the 8-10 day Ax-1 being the first. However as a part of these flights, those paying for seats will also help Axiom pave the way towards their goal in bringing their first module to the ISS in 2024 and carry out a suite of selected on-orbit studies and experiments.

Commanding the mission is Michael López-Alegría, who was one of NASA’s most experienced astronauts prior to retiring in 2012. He holds the US record for the most EVAs undertaken by a NASA astronaut (10 totalling 67 hours and 40 minutes) and is also (and quite separately) licensed to officiate at wedding ceremonies. In 2017, he joined Axiom Space as their director of Business Development, and allowing him to regain his space flight status. Joining him on the mission are US entrepreneur  Larry Connor, Israeli businessman and former fighter pilot Eytan Stibbe and Canadian philanthropist and businessman Mark Pathy, each of whom paid an estimated US $55 million to join the mission.

The Ax-1 crew: from left – Larry Connor Mark Pathy Michael López-Alegría and Mark Pathy. Credit: Axiom Space / SpaceX
Endeavour took a gentle path up to the space station over a 20 hour flight; however, docking was delayed by some 45 minutes due to an issue with the video system used by the ISS crew to monitor docking operations.

Following post-docking checks, the hatches between Endeavour and the ISS were opened, and the Ax-1 team were welcomed aboard the station by the 7-person crew. During a brief ceremony-come-video press briefing, López-Alegría – who had become the first former astronaut to return to the ISS – presented his three fellow crew members with astronaut pins. Whilst not official US astronaut pins, those presented to Stibbe, Connors and Pathy have been designed by the Association of Space Explorers, which encompasses a lot of members from 38 different countries that have flown astronauts.

Alongside of their work in support of Axiom Space, the Ax-1 crew will take part in a multi-discipline science programme of some 25 different research experiments sponsored by the ISS U.S. National Laboratory in collaboration with the Mayo Clinic, the Cleveland Clinic, Canadian Space Agency, Montreal Children’s Hospital, Ramon Foundation (named for Ilan Ramon, the Israeli astronaut killed in the Space Shuttle Columbia disaster of 2003) and Israel Space Agency.

The Axiom Ax-1 crew (to the rear) with their ISS colleagues, around them in the foreground – counter-clockwise from right: NASA astronaut Tom Marshburn (holding the microphone) ; Roscosmos cosmonaut Oleg Artemyev (in the blue, centre); NASA astronaut Kayla Barron; cosmonauts Sergey Korsakov and Denis Matveev (floating); and upside down NASA astronauts Raja Chari and ESA astronaut Matthias Maurer. Credit: NASA

As a fully private mission to the ISS, Ax-1 not only features a non-government crew launched aboard a private sector space vehicle and rocket, it is also being managed through the SpaceX flight control centre, Hawthorne, California and Axiom’s own mission control centre in Houston, Texas.

Artemis WDR: Further Issues and Delay

The Wet Dress Rehearsal for the Artemis 1 Space Launch System (SLS) vehicle at KSC’s Pad 39B continues to hit niggling problems, with a resumption of testing now pushed back until April 12th.

As I noted in my previous Space Sunday report, while it had been hoped this full test of a launch countdown procedure, including fuelling the massive rocket’s liquid propellant tanks, could be completed in a 3-day period between April 1st and April 3rd, the test ran into a series of issues that caused efforts to be scrubbed on two occasions.

The issues were now with the rocket itself, which performed flawless during the tests up until the scrubs were each called, but with support systems within the vehicle’s mobile launch tower. However, after the second set of issues on April 3rd caused a scrub, the plan had been to investigate and correct the issue in time to resume the countdown on April 4th and complete the tests ahead of the launch of the SpaceX / Axiom Ax-1 mission reported above – a launch that had already been postponed from April 3rd.

Artemis 1 and its mobile launch platform on Pad 39B at Kennedy Space Centre. Credit: NASA

As the investigations took longer than planned, on April 4th, the decision was taken to stand down WDR operations to allow the Ax-1 to go ahead, and to resume the tests on April 9th. But on April 7th, during a check on the rocket’s systems, engineers found a problem when trying to maintain helium purge pressure in the Interim Cryogenic Propulsion Stage (ICPS), the upper stage of the rocket itself.

The ICPS is based on the second stage of the Delta 4 launch vehicle. It uses a single RL10 engine to propelled the payload carrying section of the rocket – although it will be replaced by the more powerful and purpose-built Exploration Upper Stage from the third SLS flight (Artemis 4) onwards. This particular ICPS was one of the first to be completed, and had been in storage for several years awaiting the completion of the Artemis 1 core stage and boosters.

The Artemis 1 ICPS at Kennedy Space Centre, prior to its integration with the rest of the SLS rocket. Credit: NASA

The issue was traced to a check valve intended to prevent helium – used to purge propellant lines and drain propellant – from escaping the rocket., the valve failing to function as intended. To allow time for a possible fix for the problem to be developed and attempted, the decision was taken to push test resumption by to April 12th. Unfortunately, by April 9th, it became clear that the valve would need to be replaced; but rather than cancel the WDR completely, NASA has decided to complete the test as planned on the 12th – but to only perform a “minimum fill” of the ICPS tanks;  enough to prove the propellant loading system works. This, with a full load of the core stage tanks is seen as sufficient for the WDR to be completed.

Replacing the check valve will be carried out once the rocket has been returned to KSC’s Vehicle Assembly Building as a part of the post-WDR checks. However, this means that any chance of Artemis 1 making the hoped-for May launch window is now out of the question, whilst NASA is confident replacing the valve will correct the issue, it is also unlikely the turn-around can be completed in time for the rocket to make the June 6th through 16th launch window, potentially making July the earliest Artemis 1 launch opportunity.

NASA and China Plan, ESA Rehearses

While the United States and China are deep into the planning for a resumption of human missions to the Moon, the European Space Agency (ESA) is already carrying out human-controlled landings on the Moon – if only of the simulated variety.

Side-lit by the sun, its heavily cratered surface mired in shadow, the lunar South Pole – destination for both the US-led Artemis programme and China’s Moon ambition – represents a highly challenging lunar landing target. Western plans call for a largely automated landing system. However, as proven as early as Apollo 11, having a human in the loop and capable of taking over control can be a vital aspect of any flight.

Thus, the European Human-In-the-Loop Flight Vehicle Engineering Technology Study (H-FVETS has been initiated to evaluate how best to integrate human oversight into lunar landing operations.

The study uses a unique motion control simulator developed by the German Aerospace Centre (Deutsches Zentrum für Luft- und Raumfahrt; DLR) which has been adapted through software and the inclusion of a prototype lander flight deck. This allows astronauts to participate in various simulated Moon landing scenarios and experience how a lander vehicle behaves during critical flight phases and where and how a flight crew can quickly and effectively intervene where required.

The motion control simulator system at DLR Cologne, Germany, (left) operating as lunar lander simulator for testing human integration with flight systems. The big screen in the background shows the progress of a simulated lander. Credit: DLR

One such scenario involved the lander descending towards a location littered with boulders that might damage / topple it were it to land among them. ESA astronaut Roberto Vittori was able to take over the descent, take over control of the simulator and guide it a safer landing zone. In another, the autopilot experienced a technical fault, requiring Vittori to completely take over manual control of his “vehicle” and pilot it to a safe landing.

It was a beautiful run. The system offers an intuitive feel controlling a vehicle, and the simulator is an incredible machine, probably one of the best I have experienced. These experiments are showing that Europe can play a key role in the future of exploration.

– ESA astronaut Roberto Vittori

While the overall design of the Artemis Human Landing System (HLS) flight control systems have yet to be finalised, the ESA H-FVETS provides a means to identify the requirements of a dynamic flight control system that allows astronauts to rapidly respond to a developing situation during a descent to or ascent from the lunar surface.

And Now, the Most Distant Galaxy

In my previous Space Sunday update, I reported on the most distant individual star in the universe we have so far observed. Now comes news that astronomers have located the most distant galaxy yet found.

Referred to as galaxy candidate HD1, it is a “mere” 13.5 billion years old – meaning it formed just 300 million years after the big bang. Previously, the record for the oldest galaxy observed from Earth was GN-z11, some 13.4 billion years old.  In terms of their proper distance, GN-z11 is some 32 billion light years distant, and HD1 32.2 billion light years.

Finding HD1 took the combined talents of an international team of astronomers from multiple research centres lead by the Institute for Cosmic Ray Research at the University of Tokyo.  The discovery was made possible thanks to 1,200 hours of observation time conducted by multiple telescopes and observatories worldwide. These included the Subaru Telescope and the UK Infrared Telescope at the Mauna Kea Observatory in Hawaii; the Spitzer Space Telescope in orbit and the Visible and Infrared Survey Telescope for Astronomy (VISTA) telescope at the Paranal Observatory in Chile.

It was very hard work to find HD1 out of more than 700,000 objects. HD1’s red colour matched the expected characteristics of a galaxy 13.5 billion light-years away surprisingly well, giving me a little bit of goose bumps when I found it.

– Yuichi Harikane, assistant professor of astrophysics ICRR

A three-color image of HD1, the most distant galaxy candidate to date yet discovered, created using data from the VISTA telescope. The red shift demonstrates its extreme distance, and it – together with GN-z11, may alter our understanding of just how soon after the big bang galaxies first formed. Credit: Harikane et al

Observational information on HD1 is still limited, meaning its physical properties are not yet well-constrained. For instance, scientists are not yet certain if its brightness results from it being a very active star-forming galaxy or an active black hole. Either possibility presents exciting opportunities for future observations with next-generation telescopes. HD1 was selected as a target for the cycle 1 observations with the James Webb Space Telescope (JWST).

Beyond potentially establishing a new distance record, the possibility that HD1 is an early galaxy has considerable implications for astronomers and cosmologists. Basically, it would demonstrate that bright objects already existed in the Universe just 300 million years after the Big Bang. This is inconsistent with current models of galaxy formation and cosmic evolution, which theorize that the first galaxies didn’t emerge until roughly one billion years after the Big Bang.