Astronomy Daily S05E148 — "Far Side" Thursday 23 July 2026 Starship gets a second shot at Flight 13 — with a schedule caveat worth knowing about. The first far-side lunar samples reveal that Earth has been quietly shielding the side of the Moon that faces us. Astronomers debate whether the lunar far side should be closed to industry. The Milky Way's only helium nova finally steps out from behind twenty-five years of dust. And the case that our entire galaxy once turned over. Plus a skywatch closer with a straightforward piece of advice about the Delta Aquariids: do not wait for the peak.
In this episode Starship Flight 13 ● Window opens 6:45pm EDT / 2245 GMT Thursday 23 July — 8:45am AEST and 10:45am NZST Friday 24 July. ● Schedule is not locked: Starbase road and beach closure notices point to further Pad 2 testing. ● The 16 July attempt aborted at T-0 when four of 33 Raptors missed start parameters; the limit is three. ● Two Raptors were removed and replaced before this attempt. ● First-ever Starship deployment of V3 Starlink satellites — 20 of them. ● Super Heavy splashes down in the Gulf at ~7 minutes; Ship targets the Indian Ocean off Western Australia at ~65 minutes. No catch attempts. Chang'e-6 and the solar wind ● Published in Nature Geoscience by a team at the Chinese Academy of Sciences' Institute of Geology and Geophysics. ● Based on 1,935 grams of regolith returned from the South Pole–Aitken basin on the lunar far side. ● First direct laboratory comparison of solar wind implantation between the near and far sides. ● Far-side soil records faster, deeper-penetrating particles; the neon isotope ratio sits below every near-side sample measured. ● About a quarter of the solar wind exposure at the Chang'e-5 near-side site involved wind decelerated by Earth's magnetosphere. The far-side site shows none. ● Opens the possibility of using lunar noble gases as a fossil record of Earth's magnetic field over deep time. The far side debate — NAM 2026 ● Held Tuesday 21 July at the RAS National Astronomy Meeting, University of Birmingham. Convened by Prof Martin Ward. ● For the motion: Prof Joe Silk (Johns Hopkins) and Dr Jonathan McDowell (Durham Space Research Centre). ● Against: Dr Nikita Chiu (Durham) and Dr Manuel Salvoldi (aerospace engineer and educator). ● For: the far side is the only radio-quiet site near Earth — critical for detecting the cosmic dark ages, and an exceptional platform for gravitational wave detection. ● Against: commercial investment is what makes lunar exploration sustainable, and governance can let science and industry coexist. ● Audience support for the motion rose from 68% to 76% across the debate. V445 Puppis ● Presented at NAM 2026 by John Mills, University of Warwick. ● The only confirmed helium nova in the Milky Way. Erupted in late 2000, then vanished behind its own dust for over twenty years. ● Now confirmed as a white dwarf accreting from a rare stripped helium star — only a few thousand such stars are thought to exist in the entire galaxy. ● Orbital period of 3.7 days, roughly double previous estimates. Mass transfer has resumed. ● Unexplained high-speed "bullets" of possibly oxygen-rich gas travelling up to 20 million mph (~9,000 km/s) — never seen in any other nova. ● Data from ESO's Very Large Telescope, Hubble, the Southern African Large Telescope and TESS. ● Helium novae may be one pathway to Type Ia supernovae, the standard candles used to measure cosmic expansion. The Milky Way disc flip ● Presented at NAM 2026 by Kirill Batrakov, Durham University. ● Based on 25 Milky Way-like galaxies in the Auriga simulation suite, followed across roughly 11 billion years. ● Galaxies with the most slowly rotating stellar haloes shared a...
