The Great Water Mystery: Jezero Crater and the Hunt for Mars' Hidden History

Show notes Astronomers argue The Starry Night shows a real pre-dawn sky over Saint-Rémy around 22 July 1889; Roman enters science commissioning; Rubin's test camera and the Seagull Nebula; quick hits on Hera, Starship, Swift and Artemis; Skywatch with Venus at inferior conjunction. · Lead: The Night Van Gogh Saw · Roman Enters Science Commissioning · Rubin'S Test Camera And The Seagull · Quick Hits · Skywatch Sources · Kim et al., Scientific Reports — DOI 10.1038/s41598-026-73025-5 — https://doi.org/10.1038/s41598-026-73025-5 · EurekAlert — SLLAB release, 22 Oct 2026 — https://www.eurekalert.org/news-releases/1148245 · Science News — 'Was van Gogh's The Starry Night a flight of fancy or a real sky?' (Olson comment) — https://www.sciencenews.org/article/van-gogh-starry-night-real-sky-stars · Space.com — Starry Night depicts the sky on July 22, 1889 — https://www.space.com/astronomy/van-goghs-the-starry-night-depicts-the-sky-on-july-22-1889-researchers-find · Code and data — GitHub sllabinc/StarryNight; Zenodo 10.5281/zenodo.21175816 — https://doi.org/10.5281/zenodo.21175816 · NASA — Roman Space Telescope enters final commissioning phase — https://science.nasa.gov/blogs/roman/2026/10/22/nasas-roman-space-telescope-enters-final-commissioning-phase/ · NOIRLab — Seagull Nebula through Rubin's Commissioning Camera (noirlab2625) — https://noirlab.edu/public/news/noirlab2625/ · Universe Today — Even the Rubin's test camera produces stunning images — https://www.universetoday.com/articles/even-the-rubins-test-camera-produces-stunning-images · ESA — Brake! Time for ESA's Hera asteroid mission to go slow — https://www.esa.int/Space_Safety/Hera/Brake!_Time_for_ESA_s_Hera_asteroid_mission_to_go_slow · ESA Hera on X — https://x.com/ESA_Hera · New Space Economy — SpaceX targets November for Flight 15 — https://newspaceeconomy.ca/2026/10/21/spacex-targets-november-2026-for-starship-flight-15-and-its-first-stage-tower-catch/ · NASA — Recently published (Faster to Science letter) — https://www.nasa.gov/news/recently-published/ · IJR/AP — Swift expected to re-enter in early November — https://ijr.com/discover/science-2026-09-25-nasa-telescope-rescue-spacecraft-reenters-mission-fails-3e6b8d19 · EarthSky — Sun news, 22 Oct 2026 — https://earthsky.org/sun/sun-news-activity-solar-flare-cme-aurora-updates/ · Skywatch ephemerides computed in-session with PyEphem for Sydney, Los Angeles, New York, London and Saint-Rémy (1889)

Show notes Last November the Sun produced its strongest radiation storm in almost twenty years, and this time scientists were ready: neutron monitors from Cornwall to Shetland, sensors on transatlantic airliners, and weather balloons launched within the hour. A new Space Weather paper shows just how patchy the storm was, with one Shetland balloon passing aviation warning thresholds while others saw nothing. Also: a marsquake proves Valles Marineris is still tectonically active, a near-synchronised binary powers the Kepler field's most violent superflares, suspected Chinese rocket debris lands in a Borneo plantation, a correction on NASA's Artemis briefing, Hera's second braking burn, and a both-hemispheres skywatch with Venus at inferior conjunction, Mercury for the south, and the Moon with Saturn. Sources · Baird et al., Space Weather (DOI) — https://doi.org/10.1029/2026SW005279 · University of Surrey release, 20 Oct 2026 — https://www.surrey.ac.uk/news/rare-solar-radiation-storm-gives-scientists-clearest-picture-yet-flight-risks · NICT — ICAO space weather centres (ACFJ) — https://swc.nict.go.jp/en/knowledge/icao.html · Song et al., Nature Communications — https://www.nature.com/articles/s41467-026-78193-6 · Columbia/phys.org — Valles Marineris — https://phys.org/news/2026-10-giant-canyon-mars-tectonically-today.html · Kővári et al., arXiv 2610.11799 — https://arxiv.org/abs/2610.11799 · Konkoly Observatory release via phys.org — https://phys.org/news/2026-10-astronomers-uncover-powerful-stellar-flares.html · AFP via phys.org — Indonesia debris — https://phys.org/news/2026-10-indonesia-probes-chinese-rocket-fragment.html · CGTN — Zhuque-2E launch 14 Oct — https://news.cgtn.com/news/2026-10-14/China-s-Zhuque-2E-rocket-launches-10-satellites-into-space-1ReYXyOhz5C/share_amp.html · ESA — Hera braking manoeuvres — https://www.esa.int/Space_Safety/Hera/Brake!_Time_for_ESA_s_Hera_asteroid_mission_to_go_slow · NASA — Artemis update advisory — https://nasa.gov/news-release/nasa-to-discuss-artemis-acceleration-status-of-upcoming-moon-missions

Show notes The Milky Way's disc settled in two stages; metal-rich gas around Sgr A*; two mirror-image simulated universes; shadows in the Orion Bar; quick hits on Hera, Uzbekistan and Artemis; Orionid-night skywatch. Sources · IAC — Milky Way's disc formed in two very distinct stages — https://www.iac.es/en/outreach/news/research-iac-reveals-milky-ways-disc-formed-two-very-distinct-stages · Mirabal et al. — ApJL 1010 L38 — https://doi.org/10.3847/2041-8213/aeb0a3 · McGill — Gas around Milky Way's central black hole is rich in metals — https://www.mcgill.ca/newsroom/channels/news/gas-around-milky-ways-central-black-hole-rich-metals-study-finds-375101 · Ford et al. — AJ (DOI) — http://doi.org/10.3847/1538-3881/ae994d · Ford et al. — arXiv 2605.13995 — https://arxiv.org/abs/2605.13995 · Argonne — Aurora powers two of the largest cosmological simulations — https://www.anl.gov/article/argonnes-aurora-supercomputer-powers-two-of-the-largest-cosmological-simulations-to-date · UDE — New 3D model reveals hidden chemistry of stellar nurseries — https://www.uni-due.de/2026-10-16-publication-aa-brandt-gaches-3d-model-en · Gaches et al. — A&A 714 A295 — https://doi.org/10.1051/0004-6361/202660769 · ESA — Finding Hera's way: Flight Dynamics team in action — https://www.esa.int/Space_Safety/Hera/Finding_Hera_s_way_Flight_Dynamics_team_in_action · Kun.uz — Uzbekistan joins Artemis Accords — https://kun.uz/en/news/2026/10/19/uzbekistan-joins-artemis-accords-on-peaceful-space-exploration · NASA — To discuss Artemis acceleration, status of upcoming Moon missions — https://nasa.gov/news-release/nasa-to-discuss-artemis-acceleration-status-of-upcoming-moon-missions · The Planetary Society — Night sky, October 2026 — https://www.planetary.org/night-sky/night-sky-what-to-see-this-month

Show notes The Moon Is Still Shrinking Watters, Banks, Nypaver and Robinson (Planetary Science Journal, 14 Oct 2026) map more than 10,000 young thrust faults — ~8,900 lobate scarps and 2,000+ small mare ridges — with LRO's camera. Together they record about 42–46 m of radial contraction over the last ~400–800 million years, at most ~11 cm per million years. That's less than thermal models predict, pointing to a thick, porous, insulating megaregolith (or a strong elastic lithosphere) that delayed faulting. The ~4 MPa stress matches Apollo shallow-moonquake stress drops, so faults may still be growing today — relevant to siting lunar bases. A Soil Map for Mars University of Sydney PhD student Daniel Irving and Prof. Alex McBratney (Catena 275) classify almost 800 million Martian locations into 10 realms, 100 assemblages and 2,000 forms of 'areths', mapping 92% of the planet. Top candidate for plant growth, Nohibareth (score 0.93; ~72% clay, pH 6.8), covers 0.14% of the surface around Tharsis, Arabia Terra and Elysium. Candidates for study, not greenhouse sites; perchlorate and nitrogen not yet included. Euclid Finds Its First Comet ESA's Euclid discovered C/2026 S1 (Euclid) in Deep Field North images from 16–24 September, flagged by Mikko Pöntinen's moving-object software and confirmed by the Minor Planet Center on 8 October. ~1.3 billion km away on a steep, thousands-of-years orbit. Uranus and Neptune: Cousins, Not Twins Briand, Hue, Mousis, Cavalié et al. (A&A 714, A364) use upper-tropospheric carbon monoxide, including ALMA data, to infer deep oxygen: Uranus ~47–177× protosolar, Neptune ~182–342×. Contrasting C/O ratios suggest Neptune's building blocks formed closer to the Sun. Accepted version online since late August. Quick hits MMX launched 04:41:03 JST 20 Oct on H3 F10; separation ~71 min 13 s; JAXA confirms the spacecraft is operating normally. Roman's Wide Field Instrument focused to 63 nm RMS against ~90 nm required. Artemis II heat shield: 9 char-loss spots vs 103 on Artemis I. Hera's BRM-2 burn Thursday 22 October. Skywatch Orionids peak 21–22 Oct — watch between moonset and dawn (moonset Thu morning: 03:38 Sydney, 03:22 LA, 03:12 NY, 02:49 London). Mercury 16.5° up at civil dusk from Sydney. Venus at inferior conjunction ~24 Oct. Moon ~6° from Saturn 24 Oct. Full Moon 26 Oct 04:11 UTC. UK clocks go back 25 Oct, US on 1 Nov. Always use ISO 12312-2 certified filters for any solar viewing. Sources · Watters et al. — Thrust Faulting and the Late-stage Contraction of the Moon (PSJ, 14 Oct 2026) — https://doi.org/10.3847/PSJ/ae9eae · Smithsonian NASM — New Study Reveals How Much the Moon Is Shrinking — https://airandspace.si.edu/newsroom/press-releases/new-study-reveals-how-much-moon-shrinking · University of Sydney — Sydney student creates first map of Martian soils — https://www.sydney.edu.au/news-opinion/news/2026/10/16/sydney-student-creates-first-map-of-martian-soils.html · McBratney, Irving et al. — Areths and PPACS (Catena 275) — https://doi.org/10.1016/j.catena.2026.110649 · ESA — Euclid discovers new comet — https://www.esa.int/Science_Exploration/Space_Science/Euclid/Euclid_discovers_new_comet · SwRI — New ideas about origins of Uranus, Neptune — https://www.swri.org/newsroom/press-releases/swri-staff-contribute-new-ideas-about-origins-of-uranus-neptune · Briand et al. — Contrasting C/O ratios in Uranus and Neptune (A&A 714, A364) — https://doi.org/10.1051/0004-6361/202660770 · JAXA — Launch result of MMX aboard H3 F10 — https://global.jaxa.jp/press/2026/10/20261020-1_e.html · NASA — Roman team checks out main instrument, sharpens focus — https://science.nasa.gov/missions/roman-space-telescope/ · NASA — Rigorous analysis confirms Artemis II heat shield performance — https://www.nasa.gov/missions/artemis/artemis-2/rigorous-analysis-confirms-nasas-artemis-ii-heat-shield-performance/

MMX: A Round Trip to Phobos JAXA's Martian Moons eXploration mission launched on schedule on H3 Flight No. 10 at 04:41:03 JST on 20 October 2026 (19:41 UTC 19 Oct; 06:41 AEDT Tue; 15:41 EDT / 12:41 PDT / 20:41 BST Mon). Mars orbit August 2027, Phobos quasi-satellite orbit from September 2027, Idefix rover (CNES/DLR) release early 2029, landing and sampling 2030, and at least 10 g of Phobos returned in 2031 to South Australia. Eleven science instruments including NASA's MEGANE. The aim: settle whether Phobos and Deimos are captured asteroids or debris from a giant impact on Mars. Half a Giant Mirror ESO reports that nearly 500 of the ELT's primary-mirror segments are now at Paranal — more than half of the 931 being made (798 plus 133 spares for continual recoating). Safran Reosc is finishing a segment a day and the last one is in production. The ELT is more than 75% complete, with first observations with scientific instruments planned for late 2030. The Window That Closes Carr, Cen and colleagues (Nature Astronomy, 15 Oct 2026) used Hubble/COS spectra of six matched local starbursts to show ionising light escapes most in the first few million years, before supernova-driven winds load the outflow with neutral gas and shut it down. Escape fractions fall from ~21% (mean age ~2.7 Myr) to under 0.4% (~5.4 Myr). Preprint first posted October 2025. The Treble Clef Rises Again Botteon et al. (A&A; NASA/Chandra release 14 Oct) show VLSS J0318.9+5755, behind the Milky Way's plane, is a radio phoenix in a merging cluster at z ≈ 0.117: an old black-hole outburst re-lit by a cluster collision a few hundred million years ago. Spectral index above 4 between 400 and 650 MHz; electrons ~190–200 Myr old. Preprint from July. Quick hits Hera's 93-minute BRM-1 confirmed within parameters; BRM-2 on Thursday 22 October. Sentinel-3C's first images and altimetry. Swift: no NASA re-entry date yet. Skywatch Full Moon 26 Oct 04:11 UTC. Orionids peak 21–22 Oct: go after moonset (03:38 Sydney, 03:22 LA, 03:12 NY, 02:49 London on the 22nd). Mercury 17° up at civil dusk from Sydney (21 Oct). Venus inferior conjunction ~24 Oct. Moon ~6° from Saturn ~24 Oct. Mars–Jupiter 10.8° → 8.0° pre-dawn. Always use ISO 12312-2 certified filters for any solar viewing. Sources · JAXA — MMX launch on H3 F10 — https://mmx-news.isas.jaxa.jp/?p=2753 · ESA — Mars moon lander set to launch on 19 October — https://www.esa.int/Science_Exploration/Space_Science/Mars_moon_lander_set_to_launch_on_19_October · Australian Space Agency — MMX sample return — https://www.space.gov.au/node/950 · ESO ann26009 — More than half of the ELT's giant mirror is now in Chile — https://www.eso.org/public/announcements/ann26009/ · Carr et al. — arXiv 2510.21197 (Nature Astronomy, 15 Oct 2026) — https://arxiv.org/abs/2510.21197 · NASA — Chandra breaks down Treble Clef's galaxy cluster collision — https://science.nasa.gov/missions/chandra/nasas-chandra-breaks-down-treble-clefs-galaxy-cluster-collision/ · Botteon et al. — arXiv 2607.06659 — https://arxiv.org/abs/2607.06659 · ESA — Sentinel-3C returns its first views of Earth — https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-3/Sentinel-3C_returns_its_first_views_of_Earth · ESA Hera on X — BRM-1 confirmed — https://x.com/ESA_Hera · NASA — Lessons learned from the Swift boost mission — https://science.nasa.gov/missions/swift/nasa-highlights-lessons-learned-from-swift-boost-mission/