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/protonmail Become a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click Here This episode includes AI-generated content.
