Lol’d at the NYT piece’s framing of SpaceX’s lunar lander as “riskiest”—something which is certainly true for Artemis III. But meanwhile SLS and Orion are what make Artemis I-IV launches cost >$4 billion *apiece*. That’s unsustainable—*riskily* so—and is why NASA went to SpaceX in the 1st place.

We've reached 6,000 confirmed exoplanets! I talked with @aussiastronomer.bsky.social about where things go from here. (A great graphic by @unamandita.bsky.social visualizes the amazing jumps in planet finds since the first ones were confirmed in the 1990s.)

Tomorrow! NASA HQ 3 PM. Free & open to the public.

Good thread.

So what I glean about this Mars announcement is that chemicals were found on Mars that on Earth are due to life, and no one knows any other way to make them on Mars. However, this is very far from knowing they *were* made by life. Reminds me of phosphine on Venus; "we don't know" doesn't mean life.

To sum up: we have 🪨 A cool rock from #Mars that may or may not hold evidence of ancient life 🛰️ An internal fight over whether NASA should spend its money on science or human exploration, and on what planet 🤔 A totally uncertain future for this amazing rock 🧪

If an exciting Mars rock isn't your cuppa, try this news from (much) farther afield. Now on @sciam.bsky.social: The best-yet measurement of gravitational waves from merging black holes confirms theories from Einstein and Hawking. By @clarakm.bsky.social. www.scientificamerican.com/article/best...

In the middle of the “second space race,” NASA scientists say we may be looking at the closest evidence yet of ancient life on Mars 🔭🧪 My story for @sciam.bsky.social with edits from @leebillings.bsky.social www.scientificamerican.com/article/is-t...

Fundamentally the #Mars announcement NASA is making today boils down to: there could have been some chemical reactions in these ancient rocks that could have been mediated by living organisms. The word "could" is doing a LOT of heavy lifting there. 🧪

Now on @sciam.bsky.social: The Mars rock that made headlines last year is still worth getting excited about. A new study says the case remains strong for potential biosignatures in the "Cheyava Falls" rock studied and sampled by the Perseverance rover. www.scientificamerican.com/article/is-t...

Today is the peak of Atlantic hurricane season. And yet, there's not even a hint of a hurricane anywhere in sight. What gives? Some cool weather stuff here: 🧪 www.scientificamerican.com/article/atla...

Did you know there was a play called Oxygen in 2001 taking jabs at the Nobel Prize Committee? Did you know CO2 is the Story of Everything? Our physics editor @leebillings.bsky.social talked to @peterbrannen.bsky.social about it earlier this summer! www.scientificamerican.com/article/carb...

If we’re going to find life, TRAPPIST-1e might be our best bet. By next year, we should know for sure if this alien planet has an atmosphere. But already there is excitement at hints this is not a barren world. Story by me in @sciam.bsky.social www.scientificamerican.com/article/jwst...

Now on @sciam.bsky.social: For the 1st time, we’ve seen hints of an atmosphere around a potentially habitable exoplanet. If confirmed, this would be a monumental discovery, opening a new era in the search for life beyond Earth. By @astrojonny.bsky.social. www.scientificamerican.com/article/jwst...

Now on @sciam.bsky.social: Is Golden Dome, Trump’s missile shield plan, destined to be a pillar of U.S. defense or a trillion-dollar boondoggle? Even the experts don’t know—which probably isn’t a good thing. Important story by @raminskibba.bsky.social. www.scientificamerican.com/article/u-s-...

So @peterbrannen.bsky.social's The Ends of the World was super great but even if I was unfamiliar with his writing I would buy his new book based on this quote alone 🧪

People. This book is SO GOOD. Truly -- I am about 70% the way through and the way Peter explains and synthesizes and expands and provides fresh perspective is truly stunning.

“Anyone who tells you they know what even 4° C of warming or more in a century will actually mean—or what that will look like on a planet gripped by ice ages for the past 3 million years—is full of shit. Especially if they’re an economist.” Wise words from @peterbrannen.bsky.social’s great book.

Now on @sciam.bsky.social: “Kaboom” is not the sound you want a rocket to make. Yet that’s the problem facing SpaceX’s Starship. Instead of going to space, it keeps going kaboom. Will its next test flight be different? Stay tuned. By @jetjocko.bsky.social. www.scientificamerican.com/article/why-...

Now on @sciam.bsky.social: Carbon dioxide may be the most important—and most misunderstood—molecule on Earth. @peterbrannen.bsky.social explains why in his brilliant, epic new book—and in this conversation with me. I hope you read both! www.scientificamerican.com/article/carb...

NEW: The White House wants to kill off Juno, NASA's mission to uncover Jupiter's secrets. Fortunately, its legacy is clear. Juno's a scientist, but also an artist: it revealed Jupiter as a living van Gogh painting hanging in the sky. Me @sciam.bsky.social www.scientificamerican.com/article/how-...

In one week my book about carbon comes out, and here's some nice things some nice people have said about it. If you feel moved to do so, the link below provides a means of purchase. Thank you, that is all. www.harpercollins.com/products/the...

I wrote a short article on my research in the history of VLBI for Physics Today this week :-) pubs.aip.org/physicstoday...

Brain-reading devices are the coolest thing ever and they just crossed a rubicon - rather than relying on users to attempt to speak words, this decoder can translate "inner speech" 🧪 by @dodecalemma.bsky.social for @sciam.bsky.social www.scientificamerican.com/article/new-...

The U.S. planetary science community is sounding the alarm about plans to discard a nuclear technology that has powered dozens of NASA missions over the past 50 years

Now on @sciam.bsky.social: While the Trump administration is ordering NASA to build a lunar nuclear reactor, it's also proposing cuts that'd end NASA's nuclear-powered exploration of the solar system. Will Congress push back? By @hannah-richter.bsky.social www.scientificamerican.com/article/trum...

This is a shocking executive order that undermines the very idea of open inquiry. It turns federal grants into dispensations, subject to arbitrary and capricious withdrawal should the recipient say or believe the wrong things. www.whitehouse.gov/presidential...

So pleased to see these results published and get the attention they deserve! For the nerds, I do encourage you to read the Beichman paper, section 2 AND all the way to the end, as it details the technical challenges involved in performing these observations. Because holy sh*t, it was HARD 🔭

As I figured would happen, I'm seeing a lot of headlines and posts saying JWST saw a planet around Alpha Centauri. But that's not the case: it saw a blob of light that MIGHT be a planet. It's not confirmed. It'll likely be next year before we know. badastronomy.beehiiv.com/p/a-planet-f...

Now on @sciam.bsky.social: Brutal budget cuts for NASA could halt space missions, hinder climate research, and cede U.S. sci-tech leadership to other nations. At least, that's what John Grunsfeld—and every other living former NASA science chief—says. www.scientificamerican.com/podcast/epis...

The marketing for Avatar 3 is going nuts this year

Now on @sciam.bsky.social: Using JWST, astronomers have spotted what seems to be a gas giant planet in the habitable zone of Alpha Centauri A, the nearest sunlike star to our solar system. This is *huge* if true. By @meghanbartels.bsky.social. www.scientificamerican.com/article/jwst...

this work saved millions of lives in 2021, won the Nobel Prize in 2023, and is cancelled in 2025

From deep oceans to distant galaxies, every Scientific American cover is an invitation to explore. Now show us where curiosity takes you! 🤳 Enter the #SciAmInTheWild photo contest 🎁 Prizes include gadgets and gear to elevate your next adventure ⚠️ Terms & Conditions apply: sciam.com/180contest

Now on @sciam.bsky.social: Has JWST spied ancient light from primordial black holes? By @conorfeehly.bsky.social. www.scientificamerican.com/article/the-...

Now on @sciam.bsky.social: NASA’s new plan for a nuclear reactor on the Moon could be a lunar land grab. www.scientificamerican.com/article/nasa...

Fun little freelance thing: I have a website now! Please be gentle, I haven't built a website since the MySpace era marinakoren.com

arxiv.org/abs/2507.21402 Yeah, not possible.

Folks should be following @drjovian.bsky.social for a play by play of the #HWO25 conference this week!

If you want know all things #HabitableWorldsObservatory then follow @drjovian.bsky.social for the next two days as she posts from the #HWO25 meeting in Washington DC. Thanks Jo for keeping us posted ☺️

Theres a conference in Washington DC this week bringing together experts & enthusiasts for the Habitable Worlds Obsevatory, the proposed next-gen flagship mission for NASA. Follow along with the #HWO25 hashtag! 🔭🧪

Thrilled to be here in DC for the duration of the #HWO25 conference. Eager to learn more about this next chapter of astronomy, astrophysics, and astrobiology! If you want to chat about the project with this ink-stained wretch, ping me here or find me in person.

Now on @sciam.bsky.social, from @philplait.bsky.social: The sky is falling—from another star. There's no "Chicken Little" nonsense here, though—this is legit: Some fraction of the meteors that streak thru Earth's skies are from beyond the solar system! www.scientificamerican.com/article/inte...

‘Arsenic Life’ Microbe Study Retracted after 15 Years of Controversy A controversial arsenic microbe study unveiled 15 years ago has been retracted. The study’s authors are crying foul www.scientificamerican.com/article/arse...

This was going to be such a cool project, bummed to see it disappear: 🧪

Now on @sciam.bsky.social, by @nadiadrake.bsky.social: The U.S. has axed CMB-S4, its boldest cosmology experiment in generations. Tight budgets and crumbling infrastructure helped doom the project, which was meant to test cosmic inflation. RIP. www.scientificamerican.com/article/u-s-...

Wild! Scientists turned the world's largest X-ray laser on superheated gold and found that it had reached 33,000 degrees Fahrenheit without melting. The discovery seems to upend longstanding predictions of thermodynamics. www.scientificamerican.com/article/phys...

Really enjoyed this conversation with Lee about the benefits and risks of commercial space travel! Relatedly, I am now fascinated with the issue of space trash...

While we're posting fresh space vids, I've gotta give a shout to this excellent @wired.com Q&A with NASA astrobiologist @drfunkyspoon.bsky.social fielding all the internet's burning queries about alien life. Watch it! www.youtube.com/watch?v=1r_p...

What's the deal with private spaceflight? What are the pros & cons? Is it turning space into a playground for the ultra-wealthy, or are there benefits for all? Check out my chat with @cnn.com's @claresduffy.bsky.social on her "Terms of Service" podcast to find out: www.youtube.com/watch?v=iXnv...