¶Virgin Orbit flies again. After a Time Square publicity stunt showing off a mockup rocket, Virgin Orbit’s “Above the Clouds” mission air-launched successfully and delivered seven satellites: four DOD Space Test Program (STP) experiments (two 3U sats that will test cubesat rendezvous and docking, a NASA-sponsored 3U university cubesat, and a 3U AFRL sat testing a satellite black box recorder that can talk to the Globalstar network), two SatRevolution sats (one EO sat and one testing water-fueled thrusters), and one from Spire, added at the last minute. Spire’s satellite, the 3U Adler-1, was built for the Austrian Space Forum to study the space micro-debris environment with its deployable 0.3 m² piezoelectric array and short-range radar. Virgin Orbit has five additional launches planned for 2022, including two from England.
LauncherOne ignites after dropping away from Cosmic Girl, Virgin Orbit’s modified 747 carrier plane.
¶SpaceX’s bus route to LEO continues. On the same day as Virgin Orbit’s flight, SpaceX's Transporter-3 rideshare delivered 105 small satellites to LEO (slo-mo launch video) and its booster returned to complete a 10th flight and landing. “Remarkably, this single Falcon 9 rocket first stage has now launched 550 satellites into orbit, as well as one Cargo Dragon and one Crew Dragon. It has flown, on average, every two months since its first launch [in May 2020].” In an example of launch being fully commoditized, Spire had satellites on both Transporter-3 and Above the Clouds. The flight’s largest payload was the 170 kg Ukrainian Sich 2-1 EO satellite and its most numerous were Planet’s 44 SuperDoves and 8 Tevel amateur radio cubesats from Israeli students. Here’s a small sampling of the other payloads and their purposes: 1 Umbra, 2 ICEYE, and 2 Capella synthetic aperture radar sats; 4 Spire weather and ship tracking satellites, as well as ship tracking and ocean science sats from Unseenlabs, the Norwegian University of Science and Technology, and South Africa; 3 Kepler Communications data relay sats; German startup OroraTech’s first thermal infrared cubesat for wildfire spotting (in collaboration with Spire); IoT sats, including Dubai Electricity and Water Authority’s DEWA-SAT 1 and NuX-1 by NuSpace with a LoRaWAN IoT payload and other experimental components; and, Sen’s 16U Ultra HD video sat ETV-A1. There were also a whole bunch more. Delivery was organized via several aggregators and integrators: ISILaunch (66 sats), D-Orbit (6 sats launching from their ION satellite delivery vehicle), Exolaunch, and Spaceflight (3 sats, with 10 cubesats remanifested after their Sherpa tug was removed due to a chemical propulsion leak). Yet another busload of satellites is scheduled for delivery on Transporter-4 in April.
¶The Tonga eruption. The explosive news over the weekend was the sudden eruption of Tonga’s Hunga Tonga-Hunga Ha'apai submarine volcano, releasing a shockwave detectable around the world, a plume of ash 20 km into the atmosphere, and a 2 m local tsunami (and even a 0.6 m one as far away as California, causing minor flooding in Santa Cruz which was at high tide at the time). The explosion and atmospheric shockwave were caught by Japan’s geostationary Himawari 8 and NOAA's GOES-West, and the ashfall was seen after the fact by Maxar and Planet. Scott Manley has a solid review video on what is likely the most explosive eruption ever seen from space and the most powerful on the planet in 30 years. (That said, the 1883 Krakatau volcanic explosion was probably 10x larger.) Our thoughts are with the Tongan people affected by the tsunami and now choking ashfall.
See Hunga Tonga-Hunga Ha'apai’s visible shockwave and rapidly-expanding ash cloud in the lower right.
- The Wall (Geostationary Satellites near real-time animations)
- The earliest atmosphere on Mercury was likely generated by evaporation from its 2,400 K liquid magma oceans, but “the temperatures were likely to have been so high that the vapor was not composed of water, but rock.”
- Satellite Dashboard, a dashboard and visualizer for detecting potential orbital collisions (and close approaches) between geostationary satellites.
- More early evidence from pulsar timing observations supports an anticipated cosmic low-frequency gravitational wave background generated by binary supermassive black holes as they slowly spiral in toward each other throughout the Universe.
- Martian craters are typically named after towns around the world that have fewer than 100,000 residents to avoid political pressures. Somewhat relatedly, an article about Mary Blagg, born 1858, organized and collated the names of the Moon’s craters, of which only 33 out of ~1,600 are named after women.
- 🧵 Distant Retrograde Orbits (DROs) are a class of stable orbits of the smaller object in a two object system. These are important because most lunar orbits require significant station keeping, and therefore fuel. A 70,000 km x 110,000 km DRO will be used by Artemis I for the first time (although there is a possibility that Chang’e 5 could already be in a DRO). From Earth, a DRO would appear as an object circling the moon with a period of ~2 weeks. (See also near-rectilinear halo orbits, to be tested by CAPSTONE this year and later used by Gateway.)