Astronomy Daily: Latest Space News

Show notes Six months after Artemis II swung around the far side of the Moon, NASA has published what the crew saw, said and sketched — including five faint impact flashes spotted during a 54-minute eclipse. Plus: two UCL papers that take apart the chemical evidence for hypernovae, Juno finds Jupiter's magnetodisk crumpled into ripples, and IISc simulations suggest magnetised white dwarfs could grow well past the Chandrasekhar limit. Skywatch: the crescent Moon meets Antares, Mercury and Venus favour the south, Mars leaves the Beehive, and Vesta at opposition. Artemis II Preliminary Lunar Science Report · Crew: Reid Wiseman, Victor Glover, Christina Koch (NASA) and Jeremy Hansen (CSA); lunar flyby 6 April 2026. · Five extremely faint impact flashes seen from ~74,000 km during a 54-minute eclipse behind the Moon; impactors estimated at no more than ~5 cm. · Crew-reported colours (blue = titanium-rich volcanic rock, brown = iron, green = glass); terminator observations as a proxy for south-pole lighting. · 'Hello, World' Earth image lit by moonlight; labelled southern Milky Way image (Crux, Carina, LMC). · Source: NASA Science, 'Artemis II: Sights & Sounds of Science', 7 Oct 2026 — science.nasa.gov/feature/artemis-ii-preliminary-lunar-science-report/ Hypernovae: the evidence that wasn't · Anmol Aggarwal & Ralph Schoenrich (Mullard Space Science Laboratory, UCL), two MNRAS papers; UCL release 5 Oct 2026. · Uneven ('stochastic') supernova enrichment explains three of four supposed hypernova-enriched stars; the fourth (silver- and uranium-rich halo giant) fits a neutron-star merger plus one ordinary supernova. · Source: ucl.ac.uk/news/2026/oct/ultra-powerful-star-explosions-might-not-have-occurred-after-all ; DOI 10.1093/mnras/stag610 Juno: Jupiter's rippling magnetodisk · Ruilong Guo (Shandong University) et al., Science China Earth Sciences 69(10), 2026; release 6 Oct 2026. · Repeated current-sheet crossings — four in ten minutes in one case — with reconnection signatures; a rotating, rippled sheet rather than a smooth flapping one. · Source: doi.org/10.1007/s11430-025-1870-9 White dwarfs beyond the Chandrasekhar limit · Zenia Zuraiq, Banibrata Mukhopadhyay (IISc) and collaborators incl. Christopher Tout, ApJL 2026; IISc release 9 Oct 2026. · Modified STARS code: a magnetised accreting white dwarf reaches ~2.4 solar masses vs ~1.4 without the field. · Source: iisc.ac.in/events/strong-magnetic-fields-could-allow-white-dwarfs-to-grow-beyond-the-chandrasekhar-limit/ Quick hit: Hera and MMX · ESA: Hera BRM-1, 93-minute braking burn early Thu 15 Oct; BRM-2 on 22 Oct. esa.int (Hera) · JAXA: MMX launch on H3 F10, 20 Oct 2026 04:41:03 JST from Tanegashima; samples to South Australia in 2031. Skywatch (computed for Sydney, LA, New York, London) · Tonight: crescent Moon near Antares — 1.3° from New York, 2.3° from LA and London (very low), 7° from Sydney. · Evening Mercury (24° up at sunset from Sydney) and Venus (heading to inferior conjunction ~24 Oct) favour the south. · Pre-dawn: Mars ~2° from the Beehive, Mars–Jupiter closing to ~1.2° on 16 Nov; Saturn in the evening; Southern Taurids; Vesta at opposition (mag 6.5, Cetus). · Solar safety: never view the Sun except through certified ISO 12312-2 filters.Become a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.

The coldest brown dwarf we know has weather. JWST watched water clouds thicken and thin on WISE 0855, a sunless world seven and a half light-years away — plus a star slowly eating a brown dwarf, ten minutes of X-rays after a half-second burst, a Soviet satellite breaking up over Western Australia, NASA's lunar cave hunt, and Mercury's best evening show of the year for the south. Stories Weather on a World Without a Sun Miles et al. used JWST NIRSpec to take a spectrum of WISE 0855 every 15 minutes for 11 hours. Carbon monoxide and phosphine rise and fall together as convection dredges deep gas upward, while patchy water clouds thicken and thin higher up — the first variable water clouds seen outside the Solar System. Source: University of Arizona release, 9 Oct 2026; arXiv:2609.20664 The Star That Eats Slowly ZTF J0440+2325: a red dwarf drawing gas from a 25-Jupiter-mass brown dwarf on an 87-minute orbit — the first confirmed stable mass transfer from a substellar object onto a star. Householder, Burdge et al., Nature Astronomy, 5 Oct 2026. Source: Nature Astronomy (2026); arXiv:2603.17039 Ten Minutes After Half a Second Einstein Probe caught ~560 s of soft X-rays after the 0.37 s GRB 250704B, at redshift 0.661 with no supernova — pointing to a compact-object merger and possibly a newborn magnetar. Science Bulletin, 2026. Source: DOI 10.1016/j.scib.2026.08.021; arXiv:2601.14137 A Dead Satellite Comes Apart Soviet weather satellite Meteor 2-7 (launched 1981) fragmented on 5 Oct at ~850 km, detected by LeoLabs' Western Australian radar. Cause unknown. Source: EarthSky, 9 Oct 2026; Space.com Quick hit: NASA Goes Caving on the Moon NASA's PRISM picks for the Moon Base program include GIMLI, which will probe the Marius Hills Pit for a lava tube, plus LEMS-SP and DISCO. Source: NASA RELEASE26-080, 30 Sept 2026 Skywatch Mercury at greatest eastern elongation — 24° up at sunset from Sydney vs 10° LA, 7.5° NY, 3° London. Crescent Moon near Venus and Mercury, Venus heading to inferior conjunction on the 24th, pre-dawn Mars and Jupiter for the north (Mars through the Beehive), Orionids 21–22 Oct. Source: Computed with PyEphem Sources · https://astrobiology.com/2026/10/09/first-detection-of-variable-water-clouds-outside-of-our-solar-system/ · https://arxiv.org/abs/2609.20664 · https://dspace.mit.edu/handle/1721.1/175765 · https://arxiv.org/abs/2603.17039 · https://www.arxiv.org/abs/2601.14137 · https://earthsky.org/?p=560313 · https://www.space.com/space-exploration/satellites/a-dead-soviet-satellite-just-broke-apart-in-orbit-again-experts-say-its-part-of-a-worrying-trend · https://nasa.gov/news-release/nasa-adds-new-science-investigations-for-moon-baseBecome a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.

Perseverance drove to the edge of an ancient Martian lake expecting a beach and found the inside of a volcano — rock that water has been through at least three separate times. Europe's Jupiter probe comes home on Monday night and crosses Australia in a fully dark sky. Two teams, using two completely different techniques, both find something hiding inside the most famous planetary system we have ever photographed — and an Australian instrument is in the middle of one of them. Plus: heavy water in an interstellar comet, and what it says about the star that made it. In this episode · LEAD — Three floods at the crater's edge. Candice Bedford (Purdue) and colleagues publish in Communications Earth & Environment: the Margin Unit at Jezero is igneous, not sedimentary, and records at least three distinct episodes of water — CO₂-rich groundwater making carbonate ridges, then silica associated with the lake, then a later hot-water event leaving fluorite veins. Habitability context, not a biosignature. · Juice returns. ESA confirms the third Earth gravity assist for 28 September — closest approach 11:45 UTC over the Indian Ocean, bending the trajectory ~20° and adding ~3.5 km/s. The spacecraft crosses Australia north-east to north-west 15–30 minutes earlier, in full darkness. · HR 8799. Two preprints in two weeks point at a fifth, inner planet — one from archival JWST aperture-masking data (~7 au, a few Jupiter masses), one from Gaia astrometry (2–3 au, 10–14 Jupiter masses). They do not obviously describe the same object. Neither is peer-reviewed. · 3I/ATLAS. A modelling paper explains the high deuterium-to-hydrogen ratio measured in March as consistent with formation around a low-metallicity — meaning old — star. · Quick hit: Starship Flight 14 still targeting 28 September; Crew-13 still 'no earlier than early October' on NASA's own page; Albania signs the Artemis Accords as the 73rd country. · Skywatch: the equinox as an instant rather than a date, the Juice pass over Australia, Venus and Mercury for the south, Mars and Jupiter before dawn for the north, and Saturn heading into opposition. Sources and further reading · Bedford, C. C. et al., 'Lake- and groundwater-associated alteration of the olivine-rich Margin unit in Jezero crater, Mars', Communications Earth & Environment (2026). DOI 10.1038/s43247-026-03997-9 · NASA/JPL, 'NASA Discovery Reveals Complex Water Systems on Early Mars', 21 September 2026. · ESA, 'Juice to fly past Earth for third gravity assist', 21 September 2026. · Nguyen, J. S. et al., 'A Candidate Innermost Fifth Planet In the HR 8799 System Revealed By JWST NIRISS Aperture Masking Interferometry', arXiv:2609.10507. · Lagrange, A.-M. et al., 'A fifth companion in the HR 8799 system revealed by Gaia', arXiv:2609.20996 (submitted to Nature Astronomy). · Furuya, K., Cordiner, M., Bockelée-Morvan, D. et al., arXiv:2609.12370. · NASA OIIR, 'NASA Welcomes Albania as Newest Artemis Accords Signatory', 21 September 2026. Skywatch figures computed in-session with PyEphem 4.2.1 for Sydney, Los Angeles, New York and London. Times are local unless marked UTC.Become a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.

SHOW NOTES Black hole jets follow one universal rule Adelle Goodwin (Curtin University / ICRAR, Forrest Research Foundation Fellow) and Andrew Mummery (Institute for Advanced Study, Princeton) show that supermassive black holes launch their outflows at the same critical accretion rate as stellar-mass black holes — about 2% of the Eddington limit — making accretion-outflow coupling scale-invariant across seven orders of magnitude in mass. Nature Astronomy, 17 September 2026. DOI: 10.1038/s41550-026-02951-1 JWST's Little Red Dots are black hole seeds caught mid-growth Sunmyon Chon, Shingo Hirano, Tomoaki Ishiyama, Seok-Jun Chang and Volker Springel ran fully cosmological radiation-hydrodynamic simulations on Japan's ATERUI III supercomputer and produced heavy black hole seeds of about a million solar masses, whose optically thick discs generate exactly the broad hydrogen emission seen in Little Red Dots. Nature 657, 621-625, 16 September 2026. DOI: 10.1038/s41586-026-10985-8 Earth's centre of mass moves about half as far as we thought Donald Argus, Felix Landerer and colleagues at NASA's Jet Propulsion Laboratory, with the University of Nevada, the University of Montana and the Helmholtz Centre for Geosciences, revise the annual oscillation between Earth's centre of mass and its centre of figure down from roughly 11 millimetres to about 4 to 5.5. Geophysical Journal International, ggag314. DOI: 10.1093/gji/ggag314 Two numbers explain the weather on a world 20 light-years away Merle Schrader and colleagues at Trinity College Dublin applied principal component analysis to one rotation of JWST spectroscopy of the brown dwarf SIMP 0136 and found two components — temperature and vertical cloud structure — account for all the detectable variability. Astronomy & Astrophysics, open access. DOI: 10.1051/0004-6361/202660109 The Sun goes blank With only active region AR4528 left on the Earth-facing disc and rotating out of view, the Sun was on the verge of its first spotless day since 24 February 2026 — which itself ended a 1,335-day run of continuous sunspot activity stretching back to June 2022. Skywatch: Venus at greatest brilliancy, first quarter Moon, Observe the Moon Night Venus reaches greatest brilliancy on 18 September at magnitude -4.8; the Moon reaches exact first quarter at 20:43 UTC the same day, setting up International Observe the Moon Night on Saturday 19 September. All times and altitudes in this segment were computed for Sydney, Los Angeles, New York and London. SKYWATCH — COMPUTED REFERENCE Computed in-session with PyEphem 4.2.1. Local times. Sydney on AEST (UTC+10); Los Angeles PDT; New York EDT; London BST. City Sunset Venus alt Venus sets Mercury Mars pre-dawn Sydney 17:45 39.2 deg 20:58 (3h13m) 16.4 deg (sets 1h20m) 20.4 deg Los Angeles 18:52 14.3 deg 20:10 (1h19m) 8.8 deg (sets 0h43m) 48.4 deg New York 18:56 10.3 deg 19:59 (1h03m) 7.0 deg (sets 0h38m) 46.1 deg London 19:04 3.6 deg 19:32 (0h28m) 3.9 deg (sets 0h26m) 40.6 deg · Venus greatest brilliancy: 18 September 2026, magnitude -4.8. Disc 39.6 arcsec, 26% illuminated. · By 22 September the disc has grown to 42.3 arcsec but the lit fraction has fallen to 22.7% — the two changes nearly cancel, which is why listings disagree on the date. The peak is genuinely flat. · Moon reaches exact first quarter 18 September at 20:43 UTC = 06:43 AEST Sat 19 Sep / 16:43 EDT Fri 18 / 13:43 PDT Fri 18 / 21:43 BST Fri 18. · Moon altitude at sunset: Sydney 81.6 deg (near overhead), Los Angeles 27.1 deg, New York 20.4 deg, London 9.4 deg. · International Observe the Moon Night: Saturday 19 September 2026. NASA event at the U.S. Space & Rocket Center, Huntsville, 5:30-8:00pm CST. · Pre-dawn Sat 19 Sep at nautical dawn — Jupiter: Los Angeles 26.4 deg, New York 25.1 deg, London 21.9 deg, Sydney 8.9 deg. · Mars-Jupiter separation: 22.9 deg on 18 Sep, 12.0 deg mid-October, 1.2 deg mid-November 2026. · Saturn is up essentially all night; sets 06:47 Sydney, 07:55 Los Angeles. Opposition 4 October 2026, disc 19.6 arcsec, rings approx 7 deg open. · September equinox: a single instant, 00:05:09 UTC on 23 September 2026 — evening of the 22nd in the Americas, mid-morning of the 23rd in Australia. · All figures computed in-session with PyEphem 4.2.1 for the four reference cities. Sydney is on AEST (UTC+10); daylight saving begins 4 October. Become a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.

First starlight from Roman, a shorter fuse on the Solar System, weapons in orbit, and a globular cluster hiding behind the dust Roman opens its eye — and finds it has twice as long to look NASA has activated the Nancy Grace Roman Space Telescope's Wide Field Instrument, a 300-megapixel infrared camera built around eighteen detectors, with a field of view at least a hundred times larger than Hubble's infrared field — a patch of sky bigger than the full Moon in a single exposure, at Hubble-comparable sharpness. The instrument reached its operating temperature of −143 °C on 11 September; detectors and the calibration system came up across the 11th and 12th; the element wheel turned in microgravity for the first time on the 12th; the focus mechanism was verified on the 13th. Roman then took its first starlight image — deliberately out of focus, and exactly as intended: a baseline diagnostic that proves the optical path is clear and every detector is live. Sharp science images are expected by early 2027. The Coronagraph Instrument has completed initial communications checkout from Caltech/IPAC and is running 30-day decontamination cycles at room temperature. Separately, NASA published the numbers from Roman's first mid-course correction: better than 99% accurate, using about 18 kg of a 200 kg propellant budget, on a spacecraft that launched lighter than its allowance. Jamie Dunn (Goddard): Roman has fuel for at least 22 years of potential science operations, against a design life of ten. Caveat kept on air: that is a fuel figure, not a funding or hardware figure. Why it matters: Roman's High-Latitude Time-Domain Survey measures cosmic expansion with Type Ia supernovae, and its High-Latitude Wide-Area Survey probes cosmic acceleration across more than 5,000 square degrees through weak lensing and galaxy clustering — two independent handles on the dark energy question that Monday's Australian-led supernova compilation sharpened but could not settle. A doubled mission means a longer lever arm in time, which in this measurement is everything. Caltech: the Solar System's dynamical fuse is far shorter than we thought Konstantin Batygin, Jim Fuller and Fred Adams (Caltech), 'Terminal instability of the Solar System triggered by stochastic solar mass loss', arXiv:2609.12494, posted 11 September and accepted to the Astrophysical Journal Letters. The standard estimate for how long the giant planets hold their architecture — about 10¹⁸ years — assumes the dying Sun sheds mass smoothly. Observations of white-dwarf recoil indicate mass is instead lost in discrete, independently directed ejections, so planetary orbits take a random walk. In simulations, roughly 40% of systems are disrupted or violently scattered before white dwarf formation and about 90% within ~3 billion years after, cutting the outer Solar System's dynamical lifetime to around a gigayear past white dwarf formation. Framed on air as a prediction to test — planetary systems around old white dwarfs should be rarer and more chaotic — with the granularity of the mass loss named as the number to go and measure. The United States says, for the first time, that it has weapons in orbit Secretary of the Air Force Troy Meink, speaking on the opening day of the Air & Space Forces Association's Air, Space & Cyber Conference at National Harbor, Maryland on Monday 14 September: the United States now has 'on-orbit space control weapons capable of defending the joint force against hostile adversary actions'. It is the first public US acknowledgement of offensive capability in orbit. No systems, numbers, locations or timelines were disclosed. A Space Force spokesperson defined space control as employing 'kinetic and non-kinetic means to affect adversary capabilities through disruption, degradation and even destruction, if necessary'. Gen. Douglas Schiess, Chief of Space Operations, said the following day that 'it was time' to talk about it, citing Chinese and Russian anti-satellite advances. Covered factually, with both the deterrence and the arms-control readings presented, and with orbital debris as the physical consequence that outlasts any dispute. Australian context: Operation Olympic Defender and Defence Space Command. Rubin finds a globular cluster hiding behind the dust Aashay Pai, William Cerny, Andrew Pace, Alex Drlica-Wagner and colleagues, 'Rubin Observatory Reveals a Dust-Shrouded Halo Globular Cluster in Ophiuchus', arXiv:2609.15872, posted 14 September. Rubin-GC1 was found in Rubin's Early Data Preview 2 — not the survey proper — in the direction of the galactic bulge, behind heavy dust and a crowded foreground. It sits about 31 kiloparsecs away, roughly 100,000 light-years, out in the Milky Way's halo. Half-light radius ~5 pc, absolute magnitude ≈ −2.4, placing it in the faint tail of the globular cluster luminosity function; age ≈ 9.2 billion years; moderately metal-poor. Gaia DR3 proper motions and phase-space modelling point to an origin in the Sagittarius dwarf spheroidal — an accreted cluster, not one of our own. Spectroscopy is the confirming next step. Reusable framing, now used four times in a month: catalogues are detection limits, not censuses. Quick hit — Starship Flight 14 has a firm date SpaceX has published and the FAA has cleared Flight 14 for Tuesday 22 September, a 75-minute window opening 08:15 EDT / 12:15 UTC (22:15 AEST on the 22nd). This is the first orbital attempt: six orbits at about 275 km, then a Pacific splashdown west of Chile roughly ten hours after launch. The payload is 26 Starlink V3 satellites — the first flight of the next-generation satellites designed for Starship — three of them carrying cameras to photograph the ship's heat shield during re-entry. Super Heavy splashes down in the Gulf about seven minutes after liftoff. No tower catches on this flight, for either stage, confirming the correction we carried on 12 September. Skywatch — both hemispheres Tonight: a five-day-old waxing crescent Moon beside Antares — 2.5° apart and 60° up from Sydney, 5.5° apart and 18° up from Los Angeles, nearly 7° apart and 12° up from New York. The September ecliptic tilt again. Friday 18 September: Venus at greatest brilliancy, about magnitude −4.8 — brightest not when fullest but when the product of a thinning crescent (~26% lit) and a swelling disc (~39 arcsec) peaks. Steadied binoculars will show the crescent. Venus sets ~3h15m after the Sun from Sydney, ~1h20m from Los Angeles, ~1h05m from New York; northern listeners should look low in the west 20–45 minutes after sunset with a clear horizon. Mercury is a southern-only bonus at magnitude −0.4 but only 16° from the Sun: 15° up at sunset from Sydney, 3° from London. Saturn rises within about an hour of sunset everywhere and is up all night, heading for opposition on 4 October with the rings ~7° open. First quarter falls on 18 September at 20:43 UTC, setting up International Observe the Moon Night on Saturday 19 September — timed near first quarter because that is when the terminator throws long shadows. Pre-dawn belongs to the north: Mars 45–47° up at nautical dawn from Los Angeles and New York against 20° from Sydney, with Jupiter below it, and the pair closing to about 2° by mid-November. Zodiacal light returns after the 26th — false dusk in the west from the south, false dawn in the east from the north. The September equinox is a single instant, 00:05 UTC on 23 September: the evening of the 22nd in the Americas, mid-morning on the 23rd in Australia. Eye safety: never sweep the daytime sky with binoculars or a telescope while hunting Venus. Block the Sun behind a building or wall first. Eclipse glasses must carry the ISO 12312-2 certification and be undamaged, and are for looking at the Sun only. Never use optics on the Sun without proper solar filtration fitted at the front. Sources and further reading · NASA Roman blog — 'NASA Activates Roman's Primary Instrument, Checks Out Coronagraph' (15 Sept 2026) · NASA Roman blog — 'Fuel Savings Double Potential Lifetime for NASA's Roman Mission' (14 Sept 2026) · NASA — Roman Core Community Surveys · arXiv:2609.12494 — Batygin, Fuller & Adams, 'Terminal instability of the Solar System triggered by stochastic solar mass loss' (accepted, ApJL) · arXiv:2609.15872 — Pai et al., 'Rubin Observatory Reveals a Dust-Shrouded Halo Globular Cluster in Ophiuchus' · AFA Air, Space & Cyber Conference 2026 — remarks by Secretary of the Air Force Troy Meink, 14 September 2026 · SpaceX — Starship Flight 14 mission page · Astronomy Daily S05E193 — 'The Universe Changes Its Mind' (the dark energy lead this episode calls back to) · Astronomy Daily S05E187 — stellar streams (Nora Shipp co-author callback)Become a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.

Today's episode — The Weekend Wrap, Saturday 12 September 2026: OUR LEAD: A SMALLER MERCURY Mercury has been contracting for four and a half billion years as its huge iron core cools, and it writes the record on its own surface — in long lobe-fronted cliffs called lobate scarps, where one slab of crust has ridden up over another. Add up all that shortening and you get the total contraction. The trouble was that the surface record always gave a smaller number than thermal models predicted. New work led by Gaku Nishiyama at the German Aerospace Center in Berlin, published in Geophysical Research Letters and released by the American Geophysical Union on 10 September, explains the gap — and the explanation is beautifully simple. Impact debris buries the cliffs. Using MESSENGER imagery reworked with stereophotogrammetry, the team showed that the rougher the terrain, the fewer shortening structures you can find per unit area. Since faults don't know what the surface above them looks like, that correlation isn't geology — it's a detection limit. Correct for it and Mercury's total loss of diameter rises by 10–30%, from a range topping out near 16 km to as much as 23 km. That points to a larger metal core, fewer light elements in it, or a hotter start — and it closes the long-standing mismatch with the physics. BepiColombo is about ten weeks from gravity capture at Mercury, carrying a far better laser altimeter and a much less eccentric orbit. If Nishiyama is right, it should find the missing small scarps in exactly the rough ground where today's maps look suspiciously empty. Some of that data will come home through ESA's New Norcia station in Western Australia, run in partnership with CSIRO. THE WEEK THAT WAS · Monday — Isar Aerospace's Spectrum reached orbit from Andøya Spaceport in Norway on 5 September, the first vehicle ever to do it from Western European soil, carrying five university cubesats. · Tuesday — giant-impact simulations including temperature-dependent rock strength can produce an intact Moon in about five hours rather than a slowly accreting debris disc. A sensitivity result, not a new origin story. · Wednesday — Hubble and Webb together found 27 previously unknown trans-Neptunian objects down to about 5 km, and the small ones keep the colours of their birth population rather than looking like collision fragments. · Thursday — 109 localised fast radio bursts were used to measure how far galactic feedback has smoothed the clumpiness of matter, finding more cool gas in big haloes than X-ray surveys see. · Friday — population synthesis suggests magnetars are roughly half of all neutron stars at birth, not one in a hundred, which doubles the Galactic supernova rate and makes magnetar central engines affordable. ALSO IN THIS EPISODE · The Sun's superflare potential — new work from the Max Planck Institute for Solar System Research with the University of Colorado, released 10 September. Scaling the 300 strongest modern solar flares against the size of their active regions, then applying that relation to the giant sunspot group of 1947 — the largest in four centuries of observation — gives a region with enough stored magnetic energy to power a superflare. Potential, not prediction: the caveats are covered properly on air. · Rocket Lab has filed a protest with the US Government Accountability Office over NASA's ~$700M Mars Telecommunications Network award to Blue Origin, on eligibility and technical-evaluation grounds. A GAO decision is due around mid-December. · Starship Flight 14 has slipped to no earlier than 18 September — and the tower catch of the ship is deferred to a later flight, which corrects how we framed it earlier this month. SKYWATCH — BOTH HEMISPHERES · The Moon and Venus about half a degree apart in front of Spica on the evenings of 13–14 September — Southern Hemisphere observers get the better geometry. · Venus reaches greatest brilliancy on 18 September at magnitude −4.8. · SN 2026aaiv, a Type Ia supernova in NGC 7331 in Pegasus, around magnitude 12 — the week's best observing target, and far easier from North America than from Sydney. · Saturn building towards its 4 October opposition, with Dione and Tethys events in the small hours for northern telescope owners. · Mars passing 6° south of Pollux pre-dawn on 18 September. · The zodiacal light — an evening object in the west from the Southern Hemisphere, a pre-dawn object in the east from the Northern. Best chance until early October. · Eye safety: never point binoculars or a telescope near the Sun when hunting daylight Venus or twilight Mercury. Solar filters must be certified to ISO 12312-2, fitted over the front of the instrument, and inspected every time. Links & sources · Mercury contraction — Geophysical Research Letters: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2026GL124067 · Mercury contraction — AGU Newsroom release: https://news.agu.org/press-release/mercury-is-shrinking-more-than-we-thought · Superflares — Max Planck Institute for Solar System Research: https://www.mps.mpg.de/news · Superflares — release summary: https://www.eurekalert.org/news-releases/1143231 · Rocket Lab GAO protest: https://www.space.com/space-exploration/missions/rocket-lab-protests-nasas-decision-to-award-blue-origin-usd700-million-mars-orbiter-contract · Starship Flight 14 schedule: https://www.spacelaunchschedule.com/launch/starship-flight-14/ · SN 2026aaiv in NGC 7331: https://www.rochesterastronomy.org/sn2026/sn2026aaiv.html · Magnetar fraction — Nature Astronomy: https://www.nature.com/natastron/articles?year=2026 · Sky this week: https://www.astronomy.com/the-sky-this-week/the-sky-this-week-from-september-11-to-18-2026/ · ESA deep space ground stations: https://www.esa.int/Enabling_Support/Operations/New_era_for_New_Norcia_deep_space_antenna More at astronomydaily.io — full back catalogue, news feed, newsletter sign-up and listener contact form. Follow us: @AstroDailyPodBecome a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.

Today's episode — S05E180, Saturday August 29, 2026, The Weekend Wrap: Main story: The Nancy Grace Roman Space Telescope launches tomorrow, Sunday August 30, with a primary window opening 7:26am EDT (11:26 UTC / 9:26pm AEST Sunday night in Sydney) on a SpaceX Falcon Heavy from LC-39A, Kennedy Space Center; backup window Monday August 31 at 7:22am EDT. Total ascent to spacecraft deployment is about 31 minutes 31 seconds, with Falcon Heavy's side boosters landing back at Cape Canaveral roughly 7 minutes 40 seconds after liftoff. Named for NASA's first chief astronomer Nancy Grace Roman (the "mother of Hubble"), the telescope shares Hubble's 2.4-metre primary mirror but pairs it with a Wide Field Instrument boasting a field of view roughly 100 times larger at similar resolution. Its major science campaigns: the High Latitude Wide Area Survey, mapping ~2 billion galaxies to probe dark matter and dark energy; a companion supernova time-domain survey; and the Galactic Bulge Time Domain Survey, a gravitational-microlensing exoplanet hunt expected to find on the order of 100,000 new worlds, including free-floating rogue planets. A Coronagraph Instrument will demonstrate direct exoplanet imaging technology. After deployment, Roman heads for the Sun-Earth L2 point (~1.5 million km out), a month-long cruise followed by months of commissioning. The mission closes out three threads covered this week: its clearance for launch nine months early (S05E176), its Cold War spy-satellite origin story (S05E178), and its narrow escape from budget cancellation (S05E179). The week in review: ● Chang'e-7's delay, revisited: Monday's episode (S05E175) reported China's Chang'e-7 lunar south pole mission scrubbing on August 24 due to Tropical Storm Narra, with the next window estimated at about a month out. Since then, reporting has split — some outlets still cite a mid-September window, while others report a slip to February or March 2027, citing the mission's roughly 100-days-per-year favorable lighting geometry at Shackleton Crater. China's Manned Space Agency has not issued a firm new date as of this recording; we're flagging the uncertainty rather than picking a side. ● Betelgeuse's bubbling surface: ALMA's most detailed image yet of the red supergiant's actual surface shows a corrugated, hot-spotted texture, with one hot spot persisting for over seven years — possibly stirred by a newly confirmed companion star (S05E177). ● Diamond rain, decoded: A Lawrence Livermore experiment recreated Neptune- and Uranus-like interior pressures, settling a 20-year dispute over diamond's melting point and pointing toward roughly triple the energy gain in certain fusion reactor configurations (S05E178). ● The space-mirror fight: US startup Reflect Orbital has FCC approval for its first demonstration mirror satellite; a new peer-reviewed study (Kocifaj, Bakos & Kundracik) finds the planned full-scale mirrors would appear roughly 40 times brighter than the full Moon to anyone in their beam — "worse than big cities like London," per Princeton's Gáspár Bakos (S05E179). ● Starship's Ship 40 is actually heading home: hours after Friday's episode aired, Ship 40 was loaded onto the heavy-lift vessel Forte and departed Christmas Island on the ~20,000km voyage back to Starbase, Texas, expected to take several weeks. Flight 14 remains targeted no-earlier-than September 15, with Booster 21's static-fire testing now complete. Links & sources: ● Space.com — What time will SpaceX launch NASA's Roman Space Telescope on Aug. 30? (Full mission timeline) ● NASA Science — Roman Launch Countdown ● Engadget — How to watch the Nancy Grace Roman Space Telescope's launch ● Scientific American — China delays ambitious Chang'e 7 moon mission until 2027 ● SpaceNews — China delays Chang'e-7 lunar south pole landing mission launch ● CGTN — Explainer: Why Chang'e-7 can't simply launch a few days later ● Space.com — The bubbling surface of doomed supergiant star Betelgeuse has been revealed like never before ● ScienceDaily — Scientists crushed diamond beyond Neptune-like pressures — and solved a 20-year mystery ● Gizmodo — Scientists recreate the melting "diamond rain" of Neptune and Uranus. It may help fusion power ● Space.com — Massive space mirrors could be 40 times brighter than the full moon, astronomers warn ● ABC News (Australia) — SpaceX rocket begins journey back to Texas from Christmas Island ● NASASpaceFlight.com — Ship 40 arrives at Christmas Island, plans return to Starbase Follow us: @AstroDailyPodBecome a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support.Sponsor Details:Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.astronomydaily.io/nordvpn. You'll be glad you did!Get the best secure and private email on the planet. Stop your Government, google and who knows who else spying on every email you write. Do what we did and use ProtonMail. They beleive in privacy and there are no ads in their business model...yet they still provide a free forever service. Check them out and get out special deal at www.astronomydaily.io/protonmailBecome a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click HereThis episode includes AI-generated content.