The Orbital Index

Starliner’s Crew Flight Test. After 14 years of development on a program that was supposed to take seven, Boeing’s Starliner crew capsule is about to carry crew for its first time. This test flight to the ISS, helmed by two experienced NASA astronauts, could launch on its ULA Atlas V as soon as May 6th. The capsule can host up to seven astronauts, but will regularly fly with four NASA-affiliated crew members. Boeing has suggested that it will sell a fifth seat on Starliner to commercial entities, diverging from SpaceX’s pattern of selling fully commercial flights (e.g., to Axiom and through the Polaris program). Starliner underwent two uncrewed test flights in 2019 and 2022 but encountered software, clock, valve, flammable tape, and parachute issues. At least it wasn’t a cost-plus contract, so Boeing’s failure to deliver resulted in $1.5B in losses for the company instead of for taxpayers. If successful, Starliner will join Crew Dragon, its frenemy in NASA’s Commercial Crew Program (who received $2.6 billion in 2014 vs Boeing’s $4.2 billion but has been flying astronauts to the ISS for 4 years now), in routinely carrying crew to the ISS once per year. (Meanwhile, Crew Dragon, which has been doing double duty, will likely revert to the originally intended cadence of launching to the ISS annually for the CCP program as well.)

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Eris on the pad down under. Private Australian company Gilmour Space raised their three-stage, solid-fuel-with-liquid-oxidizer hybrid Eris rocket on a pad at a commercial launch site in North Queensland. Eris will be Australia’s first domestically-produced orbital rocket to attempt launch (a modified US Redstone rocket launched Australia’s first satellite from the country in 1967, and the UK's Black Arrow launched from the same range in 1971). Eris is 25 meters tall and can carry 300 kg to SSO, similar to Electron. Its third-stage regeneratively cooled, kerolox Phoenix engine is 3D printed. It could launch as soon as later this week.

Starship fuel transfer on track for 2025 demo. NASA shared that Starship’s Flight 3 intertank cryogenic fluid transfer (CFT) was “successful by all accounts,” although data is continuing to be reviewed. The Flight 3 CFT test was the completion of a 2020 Tipping Point award that funded the development of a 10-ton transfer demonstration of cryogenic liquid oxygen from Starship’s header tank (~23 t) to its main tank (~1,000 t). Hurdles for this transfer included unknown on-orbit fluid temps, fluid settling in zero-g, and temperature management of transfer lines. SpaceX’s CFT award is part of a larger effort by NASA to improve the state-of-the-art around cryogenic fluid management in space, which includes other projects like cryocooler development, radio frequency mass gauges (one was recently tested on IM-1), cryo-couplers (previously funded through another SpaceX Tipping Point award), thermal management coatings (originally discovered through a NIAC award), and liquefaction. All of these technologies will be necessary for long-term cryogenic fluid transfers and storage, a requisite for complex lunar and Martian mission profiles. Up next for SpaceX is a Starship-to-Starship transfer, currently targeted for some time in 2025. For this demonstration—a core step in enabling Starship’s ability to venture past LEO—a “target” Starship will launch to orbit, followed several weeks later by a “chaser” Ship, which will approach the target, dock, and transfer liquid to the target, with both then performing deorbit burns. SpaceX still has significant technology left to develop to flight readiness for this mission, including hot gas thrusters, relative navigation and docking systems, and CFT quick disconnects. Starship is currently on track to launch for the fourth time at the end of May, although the company still needs to submit its Flight 3 mishap investigation report to the FAA (this has previously happened relatively close to launch).

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• 63 years ago today, on a 15-minute suborbital flight, Alan Shepard became the first American in space.
• The Artemis generation of Moon Trees have found homes after 2,000 seeds from a diverse array of species (sycamores, sweet gums, loblolly pines, and giant sequoias) were flown around the Moon during Artemis I. This carries on the legacy of Moon Trees from Apollo 14, an experiment/publicity stunt that was almost forgotten until Dave Williams, head of NASA’s Space Science Data Coordinated Archive, started an online database to catalog 120+ known Moon Trees across the US. 
• Space Capital’s SPACE IQ Space Investment Quarterly report for Q1 2024 shows investments of $6.5B, up 33% from the previous quarter, weighted toward later-stage deals. Meanwhile, McKinsey and the World Economic Forum say the space economy might grow to be $1.8T by 2035.
• Relatedly, BryceTech’s Smallsats by the Numbers 2024 report has some interesting details on the 2,860 smallsats launched in 2023 (representing 63% of humanity’s upmass for the year): They were 79% comms (vast majority Starlink), 13% EO, 7% tech demos, and 1% science.
• A 3D global climate model shows that there is a knife-edge balance between a habitable world and a Venusian hell. A slight rise of the Sun’s luminosity, enough to warm the Earth by a global average temperature of just a few tens of degrees (so fortunately way more than is threatened by anthropogenic climate change anytime soon), would start a runaway greenhouse process involving the buildup of water vapor in the atmosphere (paper). “There is a critical threshold for this amount of water vapor, beyond which the planet cannot cool down anymore. From there, everything gets carried away until the oceans end up getting fully evaporated and the temperature reaches several hundred degrees.”
• Reentry looks like the hardcore KSP that we’ve (maybe) always wanted.
• Fun (seemingly coincidental) fact: If you add the masses of Mercury, Venus, Mars, and the Moon, the result is almost exactly the mass of the Earth.
• China’s Moon atlas is the most detailed ever created.