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The Orbital Index

Issue No. 258 | Feb 28, 2024

🚀 🌍 🛰

IM-1 lands on the Moon, joins the tipsy club. The first successful non-governmental lander in lunar history, and the US’s first lunar lander in 52 years, touched down on February 22nd near Malapert A crater close to the Moon’s south pole, within 1.5 km of its target. Odysseus was also the first spacecraft to use cryogenic (in this case, methalox) propulsion in deep space. It appears to have tipped over due to 2 m/s horizontal velocity at landing, joining SLIM in a run of recent landers discovering that that last step of a lunar landing is a doozy. In its current orientation, the vehicle’s high-gain antenna isn’t pointed at the Earth and solar panel exposure is limited, limiting data downlink, but systems appear to be otherwise functional and data is slowly being received, with a few landing images recently released. The final stage of landing wasn’t the only bump along IM-1’s ride. While in orbit, a malfunction of the vehicle’s laser rangefinders was noticed fortuitously when its orbit was slightly off and the rangefinder was enabled for orbit determination, only to discover that a pre-flight safety switch hadn’t been flipped to enable the system—here’s Scott Manley’s video on the subject. A last minute software update, just two hours before landing, switched the spacecraft to use a secondary NASA Doppler LiDAR package originally intended only as a demo—we imagine that software update, which IM estimated would have normally taken 30 days to develop, was a bit stressful to roll out. EagleCam unfortunately wasn’t released during landing due to the rangefinding circumstances, but may still be ejected. Onboard IM-1 are NASA’s first six CLPS payloads (c.f. Issue 255) to reach the Moon, which included the very handy LiDAR package and ROLSES, a radio astronomy experiment—see Issue 110 for a dive into the quickly-expanding world of lunar radio astronomy that this will hopefully enable. Non-NASA payloads included a material sample from… checks notes…  a Columbia Sportswear jacket to test if it could insulate propellant tanks, two digital data archives, ILOA’s cameras (c.f. Issue 256), and artist Jeff Koons’s artwork called “Moon Phases”, which appears to be on the side now resting on the lunar surface. (Perhaps it’s their status as a public company, but communications from Intuitive Machines have had nowhere near the depth and timeliness of those from Astrobotic.)

Odysseus over the Moon on February 21st before its mostly-successful landing on the 22nd.

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Tianwen-4. After Tianwen-3 (China’s Martian sample collection mission targeting a 2028 launch and 2031 return to Earth), CNSA is envisioning Tianwen-4, a mission to Callisto, the rest of the Jovian system, and Uranus. This ambitious composite mission could launch in 2029 and arrive at Jupiter, after a number of Venus and Earth gravity assists, in 2035. Before entering first Jupiter and then Callisto orbit, a separate Uranus probe would be released for a 2045 flyby (currently it would be only humanity’s second visit to the ice giant planet). Callisto is the outermost Galilean moon, one of the largest and most cratered objects in the solar system. Having a large number of craters generally indicates an ancient surface, and therefore an object that may teach us a lot about our solar system’s past dynamics. Calisto may also have a subsurface ocean. The moon’s radiation environment is easier on spacecraft than those of Ganymede, Europa, and Io which are all within Jupiter’s intense inner radiation field. Because of all these aspects, we’re excited that Tianwen-4 may even carry a Callisto impactor. Related: Galileo discovered his four namesake moons 414 years ago last month, the first moons seen beyond the Earth-Moon system which redefined how we think of our place in the Universe.

SLIM survives the lunar night. The wrong-side-up Japanese lander, which had been hibernating through the two-week-long, -130 °C lunar night and the following week of unfavorable illumination angles (due to its aforementioned tipsy state), has somewhat surprisingly responded to commands from JAXA. The mission was not originally designed to survive the frigid night time temperatures. However, in a bit of situational irony, the agency had to shut the lander down again almost immediately due to overheating of the communications equipment in the 100 °C+ lunar mid-day. Despite this temporary set back, it appears that the lander may get a longer lease on life to study its environs, including its lovingly-canine-named pet rocks. JAXA was able to snap another picture of the lunar surface while SLIM was active and plans to fill in gaps in previous data with its new lease on life. Related: SLIM’s survival also gives some hope of a post-lunar-night Odysseus revival, although the even colder environment near the lunar poles makes that less likely—heading into night, yesterday may be the last contact with the Moon’s first commercial lander.

A new image from SLIM’s navigation camera after hibernating through the lunar night. 

News in brief. The ISRO will send an Ingenuity-like helicopter named Marble (aka Martian Boundary Layer Explorer) on the successor to their Mangalyaan Mars mission Northwood Space, a startup founded by ex-Disney star Bridgit Mendler, debuted with $6M in initial funding to produce flexible, cheap, rapidly-produced ground stations Blue Origin is looking like the likely buyer of ULA — not really the best option from a competition standpointAustralian launch startup Gilmour Space raised a $36M Series D to develop their three-stage Eris rocket The UN’s Committee on the Peaceful Uses of Outer Space will start addressing concerns about the effects of satellite constellations on Earth-based astronomical imagery China launched a classified military satellite to GEO The US issued warnings to Russia against deploying a rumored nuclear-capable anti-satellite weapon Vast plans to bid on NASA’s fifth and sixth private astronaut missions to the ISS as they continue to develop their Haven-1 space station Chinese rocket engine startup Space Circling raised a $13.9M Series A A Falcon 9 launched its heaviest payload (17.5 tons) to date in a reusable configuration Portuguese startup Connected raised a $2M pre-seed to fly their 2U IoT antenna on a small commercial satellite, with the goal of eventually developing a 5G network leveraging empty payload space on satellites ESA’s second European Remote Sensing (ERS-2) satellite re-entered after 30 years in orbit The cause of Firefly’s Alpha launch mishap on Dec 22nd was determined as a GNC software bug that prevented the sending of thruster pulse commands during its second engine burn Varda Spac’s miniature drug lab successfully rentered at hypersonic speeds (~Mach 25) and landed in the Utah desert, marking the first time a commercial company has landed an orbital spacecraft on U.S. soil.

Winnebago-1, Varda Space’s in-space manufacturing capsule, blowing in the wind upon landing at a US military training site in the Utah desert.

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A massive dust storm near Olympus Mons on Mars, captured by CNSA’s Tianwen-1 (paper) and processed by Andrea Luck.