Issue No. 260

The Orbital Index

Issue No. 260 | Mar 13, 2024

🚀 🌍 🛰

Queqiao-2. China’s 1.2 metric ton Queqiao-2 lunar orbiter is scheduled to launch this month (currently 3/20), having recently arrived at the launch pad. The communication and navigation satellite wields a 4.2-meter parabolic antenna to relay comms from Chang’e-6, -7, and -8, as well as the future International Lunar Research Station (ILRS). Its predecessor, Queqiao-1, is a relay satellite in a halo orbit around Earth-Moon L2, supporting the ongoing, and quite successful, lunar farside Chang’e 4 mission. Queqiao-2 will instead enter a more stable, inclined, elliptical frozen orbit which loiters over the Moon’s south pole (24-hr period for Chang’e-6, moving it to a 12-hr orbit for CE-7 and CE-8). Due to the orbit’s stability and the spacecraft’s fuel supply, it is expected to have an >8-year lifespan. China is offering its communications services to other countries as well. The mission will deploy two experimental CubeSats, Tiandu-1 (61 kg) and Tiandu-2 (15 kg), to test lunar navigation and comms technologies including satellite-to-ground laser ranging and inter-satellite microwave ranging. Queqiao-2 also carries its own scientific payloads: an extreme ultraviolet camera, a neutral atom imager, and a very long baseline interferometry (VLBI) experiment.

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PY4. A four-cubesat swarm of PyCube-powered spacecraft launched on Transporter-10 last week. Developed by Carnegie Mellon’s Robotic Exploration Lab with funding from NASA AMES, this mission seeks to demonstrate spacecraft-to-spacecraft ranging, in-orbit navigation, and coordinated simultaneous multi-point radiation measurements—all with low size, weight, power, and cost. These spacecraft, each just 1.5U, are built on top of PyCubed which offers a rad-tested avionics board for a mere $250. To simplify software development, the entire PyCubed system is programmable in Python (hence the name) and runs in MicroPython, a real-time interpreter that is specifically designed for low-power, embedded systems. PY4 is also saving cost and space by forgoing reaction wheels and propulsion, relying solely on magnetorquers for 3-axis attitude control. The mission also has a stretch goal of differential drag maneuvering, which would be an impressive feat given the under-actuated pointing mechanisms. PY4 is the third mission to use the PyCubed platform, with previous flight heritage found on the V-3RX mission and on a suborbital test flight in a commercial high-altitude balloon. With contact already established, PY4 is well on its way to breaking ground in rapid turn-around swarm technology while also proving the merits of the platform’s cost and space efficiency. — by Orbital Index Assistant Editor Sarajane Crawford, who works on CubeSats in Colorado and spends the rest of her time outside.

PY4’s 1.5U CubeSats awaiting flight in NASA’s Small Spacecraft Technology Lab.

Chang’e-6: the first lunar farside sample return. Under the national Chinese Lunar Exploration Program (widely known as Chang’e or CE), the CE-6 sample return mission is progressing towards its launch, potentially as soon as early May. CE-6 is the first of three missions in the program’s final Phase IV which aims to culminate with the establishment of a research station near the Moon’s south pole. To date, the Chang’e program’s seven missions have boasted a 100% success rate. Nearly identical to CE-5, the ~8.2-ton CE-6 space probe consists of an orbiter, return capsule, lander, and ascender. Within a 48-hour period after landing, up to 2 kg of regolith from a depth of up to 2 meters will be collected, transferred to the ascent vehicle, and propelled into lunar orbit. From there, rendezvous with the orbiter stage and sample transfer to the Earth return and reentry module will follow. CE-6 will communicate via its dedicated relay satellite Queqiao-2 (item above). The candidate CE-6 landing site is near the southern edge of the 3.9-billion-year-old Apollo impact crater within the South Pole-Aitken (SPA) basin (map below). CE-5 returned the youngest lunar sample ever collected with material from its 1.731-kg Oceanus Procellarum collection site, estimated to be ~2 billion years old. It is likely that the CE-6 sample will include SPA ejecta materials including lower crust or possibly mantle, as well as basaltic material of different ages. Successfully returned samples will provide insights into the evolution and composition of the lunar farside. International payloads for the mission were solicited in April 2019, and four were selected: ICECUBE-Q, a cubesat developed in Pakistan; Detection of Outgassing Radon (DORN) from France; Negative Ions on Lunar Surface (NILS) from Sweden; and, the INstrument for landing-Roving laser Retroreflector Investigations (INRRI) which was developed by Italy and is similar to the one flown on Schiaparelli.

Chang’E-6 will attempt to collect the first lunar farside samples, landing in the South-Pole-Aitken basin. Credit: CNSA, CSA

News in brief. NASA will receive $24.875B in FY 2024, 8.5% less than requested and 2% below what was received in 2023 Crew-7 is home after 6 months in spaceStarship IFT-3 is targeting a launch attempt tomorrow, on Pi Day, with a planned splashdown in the Indian Ocean—SpaceX hopes to reach orbit, test in-space fuel transfer, open Starship’s payload door, and perform an in-space engine re-ignition SpaceX launched three Falcon 9s in 20 hours (imagine what Starship cadence could look like in 10 years!) Iridium is acquiring Satelles for $115M, a GPS backup provider that uses satellites in LEO to generate PNT solutions Blue Origin is projecting a first Blue Moon launch in 2025 New Glenn completed initial cryogenic testing at LC-36 As an alternative to bankruptcy, co-founders Chris Kemp and Adam London took Astra private for $0.50/share, down 99% from its peak valuation Kurs Orbital, an Italy-based satellite rendezvous, docking, and servicing startup founded by the former head of Ukraine’s space agency, closed a $4M seed round The most massive object ever tossed overboard from the ISS (a three-ton hunk of old nickel-hydrogen batteries) mostly burned up in the Earth’s atmosphere after being jettisoned from the station three years ago Stratolaunch’s massive aircraft Roc took its first flight with a real release payload: the Talon-A vehicle, which came close to reaching its intended hypersonic speed Lumen Orbit, a new Seattle-based startup raised $2.4M to develop a VLEO constellation that will process data in space to reduce downlink times JPL finished building the CADRE trio of moon rovers that will fly on IM’s third lunar mission next year.

The trio of Moon-bound rovers from JPL’s CADRE demonstration showcasing their ability to drive autonomously as a team without explicit commands from the engineers in the clean room.

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A fully stacked Starship (B10 & S28) stands tall ahead of the monster rocket’s third flight test, set to take off in the coming days (streamed in low quality only on X/Twitter, unfortunately).

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