In this new paper we showed that interstellar objects can be captured as a byproduct of stars flying by each other in the Galaxy (no planets involved). It only works for strong-enough encounters, probably just a few for the Sun during its history. It means that all stars have (sparse) Oort clouds

Meg Schwamb@megschwamb.bsky.social · 2w ago

Capture of interstellar objects during stellar encounters - Raymond et al (in press) arxiv.org/abs/2607.18551

I fell asleep and forgot my June 15th tradition of reminding the world that something amazing may have happened on June 15, 2014 -- but no one on Earth saw it.. planetplanet.net/2014/06/04/s...

For #AsteroidDay, here is a good ol' poem about, well, asteroids! planetplanet.net/2020/06/30/a...

A nice write-up of a new paper by Nate Kaib and myself by @starstryder.space. The punchline: the orbits of long-period comets appear to hold a signature of the flyby of the star HD 7977, which happened 2.5 million years ago! phys.org/news/2026-06...

Ancient stellar flyby may still be steering long-period comets today

The Gaia mission has allowed researchers to understand the motions of stars like never before, even revealing possible interactions between our solar system and nearby stars. Planetary Science Institu...

phys.org

I never thought I'd get the chance to shake hands with the president and have a one-on-one chat -- for a solid 15 seconds, during which one subject of conversation was, indeed, my tie (thanks to Marisa for suggesting it!)

Left: the comet in Deep Impact (1998) Centre: the comet in Armageddon (1998) Right: an actual, real-life comet (2015)

@elizabethtasker.bsky.social made an amazing and amazingly clear all about sample return mission from asteroids. Well worth your time!

Elizabeth Tasker@elizabethtasker.bsky.social · 3mo ago

Hayabusa, Hayabusa2, and OSIRIS-REx: three missions 🛰️ to three different asteroids 🔭 that risked everything to bring a sample back to Earth 🧪. These are some of humanity's most difficult robotic missions. Why take on such audacious challenges? [🧵: 1/4]

I love this new paper about planets in AGN disks around supermassive black holes! arxiv.org/abs/2605.19241 Naturally, it also helps to motivate some of the crazy planetary systems I've built: planetplanet.net/2018/06/01/t...

Active Galactic Nucleus Tori: Potential Birthplace to Millions of Planets

The outer regions of AGN disks have temperatures similar to those of circumstellar disks, permitting dust condensation. Therefore, planet formation and growth could be active in these dust tori throug...

arxiv.org

For your Monday, here's one of the JWST Deep Field images. This is a portion of the sky about one-fifth the size of a full Moon. And it contains THOUSANDS of galaxies—some of which extend back to when the Universe was a couple of billion years old. The redder a galaxy, the farther away it is.

how have I never seen this Georgia O'Keefe painting called "Ladder to the Moon" 😭

This week in my "Planets in Science Fiction" class, I will be discussing the amazing short story "Nightfall" by Isaac Asimov and its insights into the nature of scientific bias. Also be sure to check out the incredible work of @planetplanet.bsky.social at planetplanet.net.

It's official. I just took over as the new director of the Laboratoire d'Astrophysique de Bordeaux (@labastrobordeaux)! It's a whole new gig -- wish me luck!

Laboratoire d'Astrophysique de Bordeaux | LAB@labastrobordeaux.bsky.social · 6mo ago

🚀 Nouveau chapitre au @labastrobordeaux.bsky.social ! @planetplanet.bsky.social et Benoît Lavraud prennent la direction par intérim Objectifs : exceller en instrumentation, renforcer la gouvernance et placer l’humain au cœur du labo To infinity and beyond! 🌌 astrophy.u-bordeaux.fr/transition-a...

My new paper with Nate Kaib explores what triggered the dynamical instability that took place among the giant planets in the young Solar System. We show that the flyby of a low-mass brown dwarf or free-floating planet could have done it (probability ~5%). ui.adsabs.harvard.edu/abs/2025arXi...

Last week, my son Zack shadowed me at my department for a week. I put him to work but I gave him a choice -- and he decided to simulate rings of planets and stars orbiting a black hole. And he wrote a blog post about it for your reading enjoyment (with gif!) planetplanet.net/2025/12/13/b...

About 100 billion humans have walked the Earth. About 100 billion stars roam the Milky Way galaxy. About 10,000 humans have ever been paid to study the stars (if anyone has better data let me know). So, modern astronomers are each lucky to the tune of 1 in 10 million!

If you live in France, a new documentary about 'Oumuamua comes out Thursday evening, starting at 9pm on the France 5. Replays on france.tv after I was scientific advisor (and I show up in several places), which was a great pleasure. www.francetvpro.fr/contenu-de-p...

France TV - Replay et Direct tv des chaînes France Télévisions (ex Pluzz)

Retrouvez toutes les vidéos, articles et podcasts des programmes des chaînes de France Télévisions.

france.tv

I just realized that a couple weeks ago was the fifth anniversary of the release of my astronomy poem book: Black Holes, Stars, Earth and Mars. www.amazon.com/dp/B08LFZZWGZ

Black Holes, Stars, Earth and Mars: Astronomy poems for all ages

Black Holes, Stars, Earth and Mars: Astronomy poems for all ages [Raymond, Sean, Raymond, Owen, Tyson, Neil deGrasse] on Amazon.com. *FREE* shipping on qualifying offers. Black Holes, Stars, Earth and Mars: Astronomy poems for all ages

amazon.com

Here's a new article I wrote for @nautil.us about a new result hinting that variations in the cosmic ray flux hitting the Earth, which itself varies as the Sun oscillates vertically within the Galaxy, have a strong link to the diversity of microplankton. nautil.us/could-the-su...

Could the Sun’s Orbit Shape Evolution?

Could the Sun’s Orbit Shape Evolution? The connection between our massive star and the tiniest microplankton.

nautil.us

nautil.us/the-nautilus...

The Nautilus Reading List About the Cosmos

The Nautilus Reading List About the Cosmos: Our writers have read a universe of books on the cosmos. Here are their favorites.

nautil.us

New animation of the ultimate engineered solar system for a talk I'm giving tomorrow at a sci-fi convention in Lithuania. It has 400 rocky planets in the habitable zone of a single Sun-like star It's perfectly stable (I simulated it out to about a billion years) planetplanet.net/2017/05/03/t...

AAS members are on the Hill today to #SaveNASAScience and advocate for sustained funding for NASA, NSF, and our nation's other science agencies! Help us amplify their voices by calling and writing to your Congressional offices today: aas.org/action-alert...

In my new @nautil.us article, I use a lot of recent research to argue that rocky exoplanets on eccentric orbits are often very good candidates for life. (At least, eccentric/inclined orbits should not be used as a negative for habitability) nautil.us/wild-orbits-...

Wild Orbits Prime Planets for Life

Looking for habitable worlds? Check the ones with extreme swings.

nautil.us

Here's something new and weird -- eccentric rings of co-orbital planets. They are stable indefinitely, from an orbital point of view. Could they actually form and exist? planetplanet.net/2025/09/02/e...

Flashback to 2012 when I ate the Sun (Photo from the top of Vulcano in Sicily)

Imagine the complicated and precious genius of the girl who made this embroidery sampler in 1811 The Solar System, sampler, unknown maker, 1811, England. Museum no. T.92-1939. Victoria and Albert Museum, London.

Sigh. sites.psu.edu/astrowright/...

HST Has Conclusively Shown that Avi Loeb is Wrong About 3I/ATLAS

The recent JWST observations have firmly shown that 3I/ATLAS is a comet—an interesting and anomalous one in some ways, but definitely not a spacecraft. This has not stopped Avi Loeb from continuing to...

sites.psu.edu

Still can't get over @deschscoveries.bsky.social parodying Loeb, and Loeb straight-up playing out the parody a 3 days later. Is Desch a clairvoyant, or did Loeb read this mockery of him and think—hey, that's actually a great idea!—and just plagiarize him?!

My complaints have not yet been resolved. medium.com/@steve.desch...

There’s No “I” in Team. But There Is One in “ALIENS”

Yelling “Tarantulas!” in a crowded movie theater has its time and place. If you’re enduring Madame Web, everyone will be relieved you…

medium.com

Loeb’s bad science flies out faster than any one of us should have to deal with it. For a nice explanation of what’s wrong with many of his claims I have not addressed, see @hectorsocas.bsky.social ’s work here: tinieblasyestrellas.blogspot.com/2025/08/3iat...

3I/ATLAS. A cat on my balcony

(En español  aquí )  S ummary      Recently, a new interstellar object passing through our solar system has been discovered: 3I/ATLAS. Thi...

tinieblasyestrellas.blogspot.com

Today, *every* living prior leader of NASA's science directorate have released a joint letter condemning the proposed cuts to NASA science. These individuals every administration from Reagan to Biden, and all believe these cuts are insanely destructive: www.planetary.org/press-releas...

Every living NASA science chief unites in opposition to unprecedented…

The entire past leadership of NASA’s science activities have released a joint statement condemning the proposed 47% cuts proposed to the agency’s science…

planetary.org