Sarah Hörst

@planetdr.bsky.social

Professor of planetary science at Johns Hopkins. Titan’s biggest fan. Pomeranian wrangler. Runner. Love many, trust few, always paddle your own canoe. She/her. sarahhorst.com Planetdr.26 on signal

Oh wow: ESA announces it has a positive detection of the SpaceX Falcon 9 upper stage booster impacting the moon! I still haven't seen any images of a flash, but that's not surprising. It was faint. Here, they saw evidence of gas (vaporized material) in the impact plume by taking spectra.

ESO@eso.org · 4h ago

Earlier today, the discarded upper stage of a Falcon 9 rocket impacted on the Moon. As part of a coordinated observing campaign, our Very Large Telescope detected spectral lines of sodium and lithium gas in the impact plume lasting for 5-10 minutes after impact. 🔭 🧪 📷 ESO/C. Schmidt et al. 1/4

Ralph Lorenz—Huygens showed that Titan can be wet, even at low latitudes. As Dragonfly flies across Titan, the odds it’ll land in mud are low (<1%), and if so, the stickiness will be again to sticky wheat dough (and Dragonfly could still takeoff). #AOGS2026

A photograph of a sketch in my notebook summarizing Ralph Lorenz’s talk at AOGS2026. The pen and pencil sketch shows two spacecraft on the surface of Titan: Huygens and Dragonfly (loosely to scale). The two grey spacecraft sit on a rock littered orange surface with a yellow hazy sky behind them. Next to Hogan’s, I have a zoom in the regular showing how the acoustic sensor suggested that the soil was damp, with liquid sweating out of it. On the right, I show a little insect of some reel, analog dunes, which very rarely can have intradune lakes form in particular particularly rainy seasons. Situations such as this are predicted to be very rare for Titan, but the Dragonfly mission is planned to handle it.

The new #OMB rules would transform funding decisions. I don't know where I would be without #NSF funding. Thanks @agu.org for providing a way to submit comments about the latest set of disastrous OMB rule changes. Deadline Aug 24th #resist agu.quorum.us/campaign/dvw...

Submit your comment now to help stop NSF from implementing harmful grantmaking changes

A new proposed rule would rewrite the terms of U.S. science at NSF. Submit a comment today to fight back.

agu.quorum.us

🚨URGENT ADVOCACY ACTION - We can pause OMB's harmful rewrite of grant rules that insert political appointees into the funding process, but only if enough of us speak up THIS WEEK. 🚨 This is our best shot before senators leave for August recess. Send your letter: www.planetary.org/advocacy-act...

Advocacy Action Center

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If you are an expert on air quality and have 10-15 minutes to talk to me today or tomorrow about important things journalists should know while reporting on wildfires and smoke, my DMs are open, or you can email me at karen at OpenNews dot org.

Almost 11 years ago my Dad died unexpectedly. A dear friend and colleague immediately took my calendar away from me. She told me I could have one thing and she was canceling everything else.

Just as I was finishing my last row for the evening, my circular knitting needles just catastrophically failed in a way that had never occurred to me to worry about. No wonder I have trust issues

So my only advice is if one must use it, and some people are forced to do so...then treat it like a cop when it asks you ANY question. And don't answer it. Feel free to ignore it, or tell it not to ask you personal Qs. You won't hurt feelings after all.