Show notes
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



