Issue No. 130

A shorter issue this week because Ben is on vacation in the Adirondacks. ⛰🛶🥾

The Orbital Index

Issue No. 130 | Aug 18, 2021

🚀 🌍 🛰

Lucy. You may picture asteroids as mostly living in the belt between Mars and Jupiter. However, two other clusters of asteroids lead and trail Jupiter in its orbit, grouped around the giant planet’s L4 and L5 points—these are known as the Jupiter Trojans, and they contain as many 1 km+ asteroids as the main belt. Whether these objects were captured during the formation of the solar system, or during Jupiter’s disruption of the giant planets’ orbits some 600 million years later as postulated by the Nice model, they are very old and represent preserved material similar in composition to the outer planets. NASA’s upcoming Lucy mission plans to visit up to 7 of these trojan asteroids, along with one asteroid in the main belt, during its 12-year mission to study the evolution of the giant planets. Fittingly, Lucy is named for the 3.2 million year old fossilized proto-human skeleton which taught us much about our own evolution. Lucy, the spacecraft, carries a high-resolution camera, spectrometers, and will measure the masses of objects its passes via precise measurements of the Doppler shift of its radio signals at Earth to figure out how flybys change its velocity (paper). 🤯 Lucy’s flight plan is complex: two gravity assists from Earth (in 2022 and 2024), a flyby of the main-belt asteroid in 2025 (fittingly named Donaldjohanson after the discoverer of the Lucy fossil), arrival at the L4 Trojans in 2027 to study four objects (some of which are binary systems), then another Earth flyby and a slingshot to the L5 Trojans to visit another binary system in 2033. A mission extension is possible beyond 2033 as the spacecraft orbits between the L4 and L5 clouds every six years.

Lucy is scheduled to launch on Oct. 16, 2021 on a ULA Atlas V.

The Orbital Index is made possible through generous sponsorship by:


News in brief. TASS, Russia’s state-owned media outlet, accused NASA astronaut Serena Auñón-Chancellor of suffering a mental breakdown and drilling a hole in an ISS-attached Soyuz capsule (Russian article) back in 2018—NASA has denied this, and the accusation appears to be a complete fabrication designed to save face after the recent Nauka incident Nine of the 13 stuck valves on Boeing’s Starliner are now opening, but fixing the seemingly ill-fated spacecraft will likely take months Perseverance’s first sampling failed because the rock was too crumbly, but its tools will likely be fine on other rocks Firefly is hoping to attempt a first orbital launch next month The upper stage of an Indian GSLV rocket failed, causing the loss of the EOS-03 geostationary Earth imaging satellite Venus was popular last week—Solar Orbiter flew by on the 9th and BepiColombo flew by the next day on its very complex path to Mercury Varda (the space manufacturing startup that raised $46 million last week) will be using Rocket Lab’s Photon buses for their first three spacecraft Beijing-based InterSpace Explore is developing private cargo services for the Chinese space station South Korean conglomerate Hanwha has made a $300M investment in OneWeb It looks likely that on March 18th, space debris hit Yunhai-1-02, producing 37 trackable objects, but potentially leaving the craft still controllable (!)—this is the first major confirmed orbital collision in a decade Measat-3 will be moved to a graveyard orbit after it ran out of fuel two years earlier than expected  A Vega rocket launched a high-resolution Earth observation satellite and four spectrum and space weather monitoring CubeSats ● Not content with salty infographics, Blue Origin is now suing NASA over their selection of SpaceX for the HLS contract—frankly, we feel bad for the talented Blue Origin employees who mostly do not agree with Bezos’s extremely combative approach.




  • Why does Mercury have such a big iron core, relative to the size of the planet? New modeling shows that the Sun's magnetic field drew iron towards the inner solar system as the protoplanetary disk was forming into planets. The proportion of iron in each planet’s core is proportional to the strength of the magnetic field at that distance from the Sun (paper). 🤯 Related: perhaps we should build a Mercury lander?
  • JPL’s plan for the next Mars helicopter.
  • Last week we mentioned NASA’s upcoming year-long Mars analog mission (for which you can apply). The mission will be housed in ‘Mars Dune Alpha’, a 3D-printed structure by a company called ICON which has also made the first commercially available 3D-printed homes in the US.
  • The Great Salt Lake is drying up. 😬
  • SuperBIT is a 0.5m wide-field optical telescope hanging from a 532,000 cubic meter superpressure helium balloon that can float at an altitude of 40km for years. Above 95% of the atmosphere, it will image the sky continuously at night and recharge batteries during the day. For $5m, it’s a real steal. “As demonstrated by numerous test flights, the survey data generated by SuperBIT is expected to have similar quality and data collection efficiency as the Hubble Space Telescope”, but will cost some 1,000x less. Version two could have a 1.5m aperture.
  • A talk at last week’s SmallSat conference by Siegfried Janson had some interesting tidbits. First, with over 1,735 Starlink satellites now in orbit weighing ~260 kg each, they collectively represent more mass than the ISS and generate at least 17 MW of power. Second, he noted that Planet Labs’ SuperDoves have multispectral capabilities that would only have been possible in a bus-sized satellite just 10 years ago. Third, he pointed out that Super-GEO (orbital space beyond GEO) has LEO-like radiation levels above 60,000 km and can see half the planet at a time—perhaps we should be finding uses for COTS smallsats in this region of orbital space. Finally, he also stressed that we should be designing upper-stages and satellites specifically for repurposing and reuse, not just demisability.
  • Compete to build machine learning algorithms that are able to map floodwater using Sentinel-1’s global SAR imagery.
  • Carlos Niederstrasser’s annual survey of small launch vehicles now has 48 vehicles under development with payload capacities under one metric ton, up from 30 in 2015. It seems abundantly clear that not all of them will make money.

Similar to sunbeams, but slightly longer, these 36,000 light-year long rays are likely caused by dust partially blocking the light from a supermassive black hole’s accretion disk

© 2024 The Orbital Index. All rights reserved.

Powered by Hydejack v8.4.0