Space Sunday: Artemis, Starship and Stirling

On Monday, March 4th, 2023, NASA announced the people selected to undertake the first crewed mission beyond the Earth’s orbit since Apollo 17 splashed down in the South Pacific Ocean on December 19th, 1972. The four individuals – three Americans and one Canadian  –  will undertake the first crewed flight of NASA’s Orion / Space Launch System (SLS) combination on an extended flight around the Earth and then out and around the Moon and back.

Along the way the Artemis 2 mission will tick of a number of firsts as it paves the way for the first of the planned Project Artemis missions to the surface of the Moon, which will commence with Artemis 3 in December 2025 / early 2026. For the crew, it will mark the first time a woman, a person of colour and a Canadian will fly beyond Earth’s orbit – and the mission will mark the Canadian’s first trip into space after a 14-year wait.

In announcing the crew, NASA Administrator Bill Nelson used words which echoed the words  (written by Ted Sorenson) spoken by John F. Kennedy in his September 12th, 1962 address at Rice University, Texas in which he rallied public support for the Apollo effort.

We choose to go to back to the Moon, and on to Mars. And we’re going to do it together, because in the 21st century, NASA explores the cosmos with international partners. We will unlock new knowledge and understanding. We’ve always dreamed about what more is ahead. Why? Because it’s in our DNA. It’s part of us. It’s who we are, as adventurers, as explorers, as frontiers people.

– NASA Administrator Bill Nelson, April 3rd, 2023

The four crew for the mission comprise:

• Mission Commander Captain Reid Wiseman, USN. A US Naval aviator and test pilot born in Baltimore, Maryland, he was selected as an Astronaut Candidate in 2009 and flew in space on Soyuz TMA-13M, completing 165 days in orbit on the International Space Station as a part of the Expedition 40/41
• Mission Pilot Captain Victor Glover, USN. Also a naval aviator, he was selected as an Astronaut Candidate in 2013, and flew the first operational flight of the SpaceX Crew Dragon to the ISS in 2020 as a part of the Expedition 64/65 crew. He was the first African-American to actually live and work on the ISS for an extended period (a total of 167days) rather than just visit it aboard the space shuttle.
• Mission specialist Christina Koch. An engineer from Michigan, Koch is the most experienced of the crew, having already spent less than 30 days shy of a a year in orbit as a part of Expeditions 59/60/61 crews. Like Glover, she was selected for training in the NASA Astronaut Corps in 2013. However, prior to that, she was a graduate of the NASA Academy programme, and worked extensively on various space-related projects with NASA, the NOAA and various universities.
• Canadian Jeremy Hansen, a colonel in the Canadian Air Force, is the the rookie of the crew – although he has extensive experience with NASA, the European Space Agency and the Canadian Space Agency. In 2013, Hansen served as cavenaut into the ESA CAVES training, and served as an aquanaut aboard the Aquarius underwater laboratory in 2014. His inclusion in the crew is in recognition o Canada’s longstanding support of, and partnership in, US space activities, which extends in the Project Artemis.

The four were initially selected by Joe Acaba, NASA’s Chief of the Astronaut Office, a role vacated by Wiseman so that he could have the opportunity to be selected for an Artemis mission. They were confirmed to the mission by NASA senior management, and the announcement featured a further Hollywood-trailer “trailer” video from NASA.

The flight itself is analogous to the Apollo 8 round-the-moon mission in 1968. Following launch, the Orion vehicle and crew will spend an extended period in Earth orbit, carrying out a series of vehicle checks and operational tests prior to making a free return around the Moon for a Pacific Ocean splash down after around a total of 10 days from launch. The mission will not launch earlier than November 2024.

Am I excited? Absolutely. But my real question is, are you excited? I see you and I ask that, because the one thing I’m most excited about is that we are going to carry your excitement, your aspirations, your dreams with us on this mission.

– Christina Koch

The three “driving principles” for Artemis 2 have been defined as: crew safety and survival; vehicle survival; and mission success. The mission success principle, the focus is on testing out the spacecraft subsystems, including in emergency and off-nominal conditions. There are additional flight test objectives the mission will attempt to carry out if time permits to help further reduce risk for later missions. One significant difference between Artemis 1 and Artemis 2 – outside of the latter carrying a crew – is that the Orion vehicle used for Artemis 1 was pushed to the limits, the vehicle going somewhat beyond the normal operations an Orion vehicle will experience during actual missions – the idea being to ensure the vehicle can survive the extreme end of its operational envelope.

With the announcement now out of the way, the Artemis 2 crew will commence formal training for the mission starting in June 2023 – the time between being given over to the four wrapping their other duties and work programmes so as to concentrate on the training and getting to know one another as crew and friends. Part of this training will extend to the famous WET-F tank at the Neutral Buoyancy Lab (NBL) in Houston, Texas.

This 12-metre deep pool is home to a full-scale mock-up of the external modules on the ISS, and is used to train astronauts for EVA work on the station’s exterior, and a part of which is being covered to offer a training environment to help crews train for the low-light conditions at the lunar south pole. It will be extensively used for the training of the Artemis 3 crew, but the Artemis 2 crew will help check the facilities out.

More focused training will be on Orion operations, covering every aspect of the mission from pre-launch to post-splashdown and vehicle egress, together with a refinement of the overall mission parameters, spacecraft system performance checks, guidance system calibrations, etc.

SpaceX Re-Stacks Starhip as Expectations of a Launch Increase

SpaceX has completed re-stacking the first Starship / Super Heavy booster combination intended for launch, which has been taken by some to mean that the Federal Aviation Administration (FAA) is close to being ready to grant a launch licence for the attempt.

As I reported in my previous Space Sunday update, Booster 7 was returned to the orbital launch mount after both had undergone further upgrades. Following stacking, the booster went through a full propellant load test prior to Ship 24, the starship vehicle that will make the first sub-orbital launch attempt atop Booster 7, being returned to the orbital launch site at Boca Chica, Texas prior to being raised and stacked on the booster, allowing further propellant load tests to be carried out.

Excitement over the launch grew when it was noted that the FAA issued maritime and air traffic advisories for April 10th covering both the Gulf of Mexico and Hawai’i, with back-up dates of April 11th and 12th. However, these were later revised for a potential launch date of April 17th – with the FAA noting that the inclusion of any dates in its advisories did not indicate that a launch licence had, or was about to be, granted.

Space journalist Eric Berger, taking to Twitter, further dampened expectations by pointing out it is possible the FAA might actually seek an injunction against any launch attempt pending SpaceX demonstrating it has taken the required steps to protect the surrounding wetlands environment from contaminated water run-off from the launch site – although he also noted that if there are no environmental objections, it is possible the FAA will grant a licence before month-end.

The first flight will see Booster 7 attempt to lift Ship 24 into a sub-orbital trajectory before it performs a burn-back and attempts a soft splashdown in the Gulf of Mexico. Ship 24. meanwhile will continue on in what appears to be a transatmospheric Earth orbit, meaning it will fly enough to test its thermal protection system through re-entry into the denser atmosphere, but without the need to re-ignite its engines to perform a de-orbit burn beforehand. Once within the atmosphere, the vehicle will attempt a powered soft splashdown off the coast of Hawai’i.

Overall, the flight realistically has less than a 50% chance of overall success given this is a first attempt to launch a recover a brand new orbital launch system. Even if the flight achieves all of its stated goals and both the booster and the starship survive, SpaceX have a long way to go before the system is shown to by either reliable or capable of meeting stated goals – something I hope to return to in a future Space Sunday special.

Short Updates

Virgin Orbit Files for Bankruptcy

Following on from my previous Space Sunday update, Virgin Orbit has filed for Chapter 11 bankruptcy April 4th, having failed to secure two financing deals and having burned through more than US $1 billion.

Commonly known as “reorganisation bankruptcy”, Chapter 11allows the company to continue basic operations while it looks for a buyer. Virgin Investments Limited (VIL), which is also part of billionaire Richard Branson’s Virgin Group and owns 75% of Virgin Orbit, will provide an further US $31.6 million (on top of the US $65 million already given) to keep the company afloat until it can be sold. Or that is the plan: use of the funds for maintaining the company is now down to the Delaware courts, where the bankruptcy filing will be heard (Virgin Orbit being registered in Delaware).

Selling the company may prove difficult; once valued at $ 3.7 billion following floatation on the New York Stock Exchange, the company’s value has collapsed to US $65 million by the time of court filing, and its shares plummeted by a further 24% following the announcement, leaving it with minimal cash-in-hand and limited assets against its US $1 billion deficit.

China Tests a Stirling Engine in Orbit

China continues to demonstrate it has very serious aspirations when it comes to space exploration. The country has already developed a successful family of launch vehicles, completed its Tiangong-3 space station, landed robotic missions on the Moon and Mars, and has announced plans to establish it own lunar base by the end of this decade and to send crewed missions to the vicinity of Mars by 2033.

Now the China National Space Agency (CNSA) has indicated it has successfully tested a Stirling thermoelectric converter in orbit; the first successful verification of the technology in space.

More formally referred  to a closed-cycle regenerative heat engine, with a permanent gaseous working fluid. The system works in a similar manner to hydroelectric dams generate power, a Stirling unit converts heat into electrical energy through a series of piston-driven magnets. These pistons rely on a fuel source to generate heat, pushing the magnets back and forth through a coil of wire, generating electrical current. The system is more efficient than solar-powered systems and conventional batteries, as well as being .far more compact and comparatively lightweight.

As such, it’s a technology well suited to the challenges of space exploration, especially where long-duration stays and missions to locations in deep space are concerned. When coupled with a small nuclear reactor as a power source, a Stirling engine could provide extensive electrical power on Mars or in the south polar regions of the Moon where sunlight is rare. Which is why NASA is also researching the technology as part of its Kilopower Reactor Using Sterling Technology (KRUSTY) experiment – the aim being to provide compact, relatively lightweight, nuclear-powered units to provide electrical power on the Moon and Mars.

The unit tested by China was developed by the Lanzhou Institute of Physics at the China Academy of Space Technology (CAST) and transported to the Tiangong space station by the Shenzou-15 crew, who installed it in the Mengtian lab module. In all three in-orbit experiments were carried out during which the unit produced a stable power output, serving as a proof-of-concept demonstration.