¶Artemis I is back at the pad. After over a decade and somewhere between $20 and $30 billion, the first Space Launch System—the rocket for Artemis I—is now at pad 39B and ‘go’ for launch, potentially as soon as the 29th. Artemis I will send an uncrewed Orion capsule into lunar orbit (for about 40 days) and then back to Earth. The mission will shake down the full SLS ground support and launch system, the Interim Cryogenic Propulsion Stage, and the Orion capsule, demonstrating the latter’s ability to survive 32,000 km/hr lunar re-entry velocities and its crew readiness for Artemis II. This is effectively following an accelerated version of the Apollo program where Apollo 4-10 proved out parts of the Saturn V/Lunar Module/Command and Service Module system and their flight profile. It also carries numerous space radiation environment sensors (some in the form of anatomically correct torsos) from multiple space agencies to evaluate the effects of radiation on future astronauts. Post Orion separation, the Interim Cryogenic Propulsion Stage will deploy 10 small spacecraft, most of which we’ve written about before. These are really exciting solar sailing, lunar airbag flip-landing, ice probing, and bio-analyzing missions, and it’s a shame that NASA hasn’t allowed them to be re-charged after Artemis I’s delays, threatening their chances of survival… of course, they likely cost dramatically less than even one of SLS’s disposable $146M engines. It feels like we harp on SLS’s cost a lot, but at $4.1B per launch, we kind of have to (especially since SLS was in part envisioned as a more cost-effective launch vehicle than Shuttle, which ended up costing ~$1.64B/launch).
¶Skyrora test fired the 2nd stage of their orbital rocket. Last week, the UK hosted its most significant integrated propulsion test since the Black Arrow and Blue Streak programs of the late ‘60s and early ‘70s. This successful test puts Skyrora and their eponymous rocket on pace for a first orbital launch attempt sometime in 2023 from the SaxaVord Space Centre in northern Scotland—where they’ll be in a race with ABL Space Systems and Orbex for the first ground-based orbital launch from British soil. (Virgin Orbit’s Cosmic Girl will likely air-launch a Welsh-built satellite near Spaceport Cornwall sooner.) The UK’s lack of a domestic space vehicle for the past 50 years has grown more painful since Brexit, highlighted by partially-state-owned OneWeb’s struggles to find launch providers. The Skyrora XL will compete in the small launch market, carrying 315 kg payloads to SSO. One of Skyrora’s unique features is that their 70 kN Skyforce engines can burn upcycled, plastic-derived ‘Ecosene’, reducing the carbon footprint of Skyrora’s rockets significantly (if you’re wondering what kind of climate impact rockets have, Tim Dodd has an explainer video). Skyrora is following the pattern of Astra and others with modular ground support equipment to allow responsive launch from multiple locations worldwide.
| ¶(Short) Papers|
- Aubrites, a group of igneous meteorites, the first of which was found in 1836 near Nyons, France, may actually be pieces of a proto-Mercury shattered during the early evolution of our solar system. The cataclysmic event would have scattered these odd, achondritic debris and left the smaller, deeply-scarred Mercury that we see today (paper). We may have to wait for an as-yet-unplanned future Mercury sample return mission to know for sure, though.
- Ganymede’s concentric system of tectonic troughs may be the largest impact structure identified so far in the solar system, consistent with an ancient 150 km-radius impactor—which must’ve been one hell of a show.
- After last year’s 20-ton Chinese CZ-5B rocket stage passed over NYC, Michael Byers at the University of British Columbia decided to analyze the risk of death from falling debris. His model predicts a 10% chance of space debris killing someone on Earth during the next decade (paper) unless countries and companies more actively control their deorbiting stages. The uncontrolled re-entry of another Long March 5B first stage which carried the Wentian module to orbit a few weeks ago isn’t boding well for progress here.
- Magnetic effects from solar storms may cause whales to become confused and stranded (paper).
- Loeb et al want to scrape a magnet along the ocean floor of the 10km by 10km area where an interstellar meteor may have fallen in 2014 (paper). Meanwhile, others would like to look for interstellar impact craters on the Moon (paper).
- Tiny grains of dust may hop around the surface of asteroids via “electrostatic lofting”, even achieving escape velocity from very small bodies, leaving the low-dust, boulder-strewn surfaces that we’ve seen on Ryugu and Bennu (paper).
| A timelapse photo of dust grains undergoing "electrostatic lofting" in a vacuum chamber, as may happen on the surface of small solar system bodies. (Credit: IMPACT Lab).|
- Aerial fish bombing.
- An image of black hole M87*’s actual photon ring has been teased out of Event Horizon Telescope data. Phil Plait has an explanation, with videos. (This is an image of an object that is 45 million times smaller than the full Moon in the sky!) 🤯
- And, here’s NASA’s sonification of M87. (NASA also released another sonification, that time of the black hole at the center of the Perseus Galaxy Cluster, back in May.)
- We’re sharing these retrofuturistic NASA Space Tourism Posters again because they’re great.
- VIPER, NASA’s 2024 CLPS rover, will look for water and other volatiles in shadowed lunar south pole craters. Moon Monday recently included a good summary of the ambitious mission: “With temperatures during major investigations well below -180 degrees Celsius, a rocky terrain riddled with steep slopes, a near-horizon Sun causing long, moving shadows that the solar-powered rover needs to keep avoiding or face a freeze, NASA is sending VIPER to lunar hell. To get its job done under such extreme circumstances, VIPER is being designed to traverse 15-degree inclines with ease, and even 25 to 30 degree slopes if need be. VIPER should be capable of driving sideways, diagonally, or move in any direction without changing where its [sic] heading to keep its solar panels pointed at the Sun. If VIPER gets stuck in fluffy soil, it should be able to lift each of its wheels independently to dig into and sweep along the surface—a bit like swimming or inch-worming—to get out of it.” The rover has, so far, aced its tests.