Phil Plait
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Phil Plait
@philplait.bsky.social
Bad Astronomer (formerly @BadAstronomer), SciCommer, Dork. Crash Course Astronomy guy. He/him. Newsletter: badastronomy.beehiiv.com

I'm self-employed so my opinions do in fact represent my company's.
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Wanna know where all my stuff is? about.me/philplait

My book Under Alien Skies: underalienskies.com

My newsletter (Monday issues are free!): badastronomy.beehiiv.com

My fave post here on BlueSky: bsky.app/profile/phil...
Reposted by Phil Plait
We have lost a giant. Rest in peace, Joel.
In memoriam: UC Santa Cruz honors the passing of physicist and cosmologist Joel Primack, co-developer of the cold dark matter theory and a leader in linking science with public policy.

Please join us in honoring the life of a dedicated mentor and truly seminal scientist: bit.ly/4rDCZ7e
In Memoriam: Joel Primack
Distinguished emeritus professor was a towering figure in theoretical physics and cosmology, a visionary educator, dedicated mentor, and passionate advocate for the role of science in society
bit.ly
December 4, 2025 at 2:54 AM
Pretty cool halo around the Moon in Virginia just now. Ice crystals high up in the atmosphere bend the light to form the ring and can also break it up into colors like a rainbow, though the colors are usually faint. That's a hens and chicks plant lit by the Moon in the foreground, BTW.
December 4, 2025 at 2:50 AM
I'm sure it's just coincidence that Marisa keeps breaking these stories and then when the major outlets cover it hours or days later they don't link to her.
hey @nytimes.com i had the scoop on this story hours ago. add a reference in your story to my name and outlet. thanks.

www.nytimes.com/2025/12/03/u...
Trump Renames Institute of Peace for Himself
www.nytimes.com
December 4, 2025 at 2:44 AM
Yeah, I'm in. Look at that cast! Plus Gary has some game.
I'm bored today so I decided it's time to announce the secret project.
SECRET PROJECT REVEALED
YouTube video by Gary Whitta
youtu.be
December 4, 2025 at 2:42 AM
Interesting. Even though Behn lost yesterday in Tennessee, she saw a huge swing blue in that district, losing by far less than you'd expect for a +22 Trump area. Any Republican in a less than +15 point district should be very nervous about keeping their job. Voting for ACA extention would help.
BREAKING: All House Democrats have signed our discharge petition to extend the ACA tax credits.

That makes 214.

We can protect health care and lower costs — if only 4 Republicans will join us.
December 3, 2025 at 5:32 PM
My friend Kiki does solid work, and her group does too. Endorsed.
This is a critical moment for science & society. Make a difference in someone’s life today. Support the growing community of professional science communicators… our voices for science.

Help ASC by donating today.

www.associationofsciencecommunicators.org/donate/
December 2, 2025 at 9:34 PM
Over 300 times the mass of Earth and over a thousand times the volume. Just so's you know.
2017-04-03 Hubble Jupiter Portrait (Modified) - From Ian Regan - https://flic.kr/p/TqYPXv
December 2, 2025 at 6:24 PM
Paid subscribers to my newsletter can read about a dinky star with a huge planet, and why that's so weird.

Oh, did I mention that signing up now gives you a 20% discount and that this makes a great gift for a nerdy friend? Well, I just did then.

badastronomy.beehiiv.com/p/what-is-th...

🔭🧪
What is this tiny star doing with such a big planet?
A red dwarf is sporting a jovian planet, and that’s pretty weird
badastronomy.beehiiv.com
December 2, 2025 at 5:35 PM
Tennesseans of District 7! GO VOTE! Flip this seat blue!
Today's the day, Tennessee! Cast your vote for Aftyn Behn for Congress, and then join us in getting out the vote at our all-day phonebank. Every vote counts in the push to restore sanity to science policy, and send Aftyn to Congress!

Sign up for a session at tr.ee/TN07-electionday
December 2, 2025 at 2:16 PM
'tis the season
The original "Planet of the Apes" is a Christmas movie. In the first ten minutes alone it has like 2,000 Christmases.
December 2, 2025 at 2:02 PM
Morgan was an advocate for people with AIDS when it was still heavily stigmatized. She's a wonderful person.
#WorldAIDSDay We’ve lost do many friends & relatives to AIDS. Today we remember their talent & beauty & kindness. I was honored to be Rock Hudson’s date to a Lifetime Achievement Award. A gracious & lovely gentleman. We’ve lost so many, but also made so much progress #BeKind #ReachOut 💔
December 2, 2025 at 1:50 PM
Oh, is it Cyber Monday? Well, you can get a subscription to my Bad Astronomy Newsletter for a discounted price of $48/year, and/or give it as a gift subscription too. That's only about 30 cents per issue!

The whole universe, for pennies a week. 😀

badastronomy.beehiiv.com/p/holiday-sa...
December 1, 2025 at 6:06 PM
Reposted by Phil Plait
All of America is watching. Tennessee has a chance to set the example — it's time to fight for science and sanity in Congress! On election eve, join us for a phonebank with Rep. Kelly Morrison to talk to voters in support of Aftyn Behn.

It's the final stretch! Sign up at tr.ee/final-sprint
December 1, 2025 at 4:30 PM
This is a staggering cool JWST image of one of the most terrifying star systems I have ever seen. Apep is a monster… *three* monsters, actually, and blasting out radiation and dust and junk at speeds to freeze the soul.

Read all about it!

badastronomy.beehiiv.com/p/a-ridiculo...

🔭 🧪
A ridiculously jaw-dropping JWST image of a fantastically terrifying star system
Apep consists of three immense and immensely powerful stars blasting out a fierce dusty wind
badastronomy.beehiiv.com
December 1, 2025 at 4:08 PM
That's a gorgeous shot and criminally defamed by satellites.
Look at this image (and thread - use the translate service).

This one reads along the lines of:

"..Comet C/2025 A6 (Lemmon) without cleaning.

In just 15 minutes of acquisition, we counted 1,659 satellite trails (about 400 individual ones).

Words cannot describe the pollution of near space."

🔭
3/4. En esta imagen se muestra el mismo campo estelar del Cometa C/2025 A6 (Lemmon) sin limpiar.

En solo 15 minutos de adquisición, contamos 1659 trazas de satélites (unos 400 individuales).

Sobran las palabras para describir la contaminación del espacio cercano.
December 1, 2025 at 2:29 AM
12 Monkeys is the best time travel show ever made. I will not be taking any questions.
November 30, 2025 at 11:27 PM
If every one of my followers here signed up for my newsletter at the new annual 20% sale rate I would make nearly $4 million and disappear off the face of the Earth (after fulfilling the obligation of writing the issues first of course). #promise

badastronomy.beehiiv.com/p/holiday-sa...
Holiday Sale for BAN subscriptions
A 20% discount off the price, and you can also get this as a gift for someone else
badastronomy.beehiiv.com
November 30, 2025 at 6:13 PM
Wow, *two* emails in one day from two different people unfamiliar with physics claiming they have developed a Theory of Everything that has eluded tens of thousands of trained professional scientists for decades?

<plonk>
November 30, 2025 at 3:02 PM
For years (and YEARS) I've been saying do not trust VAERS reports. There is no vetting, no statistical relevancy. It's pure anecdote.
Pretty much ANY statistic you see cited to frighten you about vaccines comes from the VAERS database. (Including the recent evidence-free missive from Vinay Prasad). Here's why VAERS can NEVER be a proper source for population-level vaccine risk estimates.

Thread [1/9]
November 30, 2025 at 2:10 PM
Wow. Straight up Nazi/Stalin propaganda bullshit.
The White House web site now includes a "media bias" tracker with a leaderboard and an offender hall of shame. www.whitehouse.gov/mediabias/
November 30, 2025 at 3:57 AM
Man do I sometimes miss seing these big goofy birds hanging out around the pond in Colorado. They'd sometimes fly over my head in the yard and it was amazing. Very graceful in the sky.
A great blue heron taking flight in a Louisiana swamp. #photography
November 30, 2025 at 1:56 AM
Reposted by Phil Plait
star at 3 billion years old: i have so much light and warmth to share

star at 12 billion years old: when i finally get to die im taking all of you with me
November 29, 2025 at 10:14 PM
When we link arms and say NO, we stop fascism in its tracks.

See @taliajane.bsky.social's earlier posts for details on ICE melting in NYC.
Confirmed: Earlier this morning a photog overheard agents inside the parking garage say “dismissed,” believed to be calling off their planned mass raid.

A source tells me they had planned for *hundreds* of agents to flood Canal St. They got flooded instead.
November 29, 2025 at 6:38 PM
Looking at Flight Aware it seems to be just heavy traffic all following the same route. It looks so weird though; the rest of the sky is empty and it's unusual to see so many planes at the same time from this location. Maybe holiday traffic.
Ok this is weird. Just now I saw three airplanes in tandem flying in the same direction (NE to SW). When I looked around I saw several more older contrails to the east.
November 29, 2025 at 3:56 PM
Ok this is weird. Just now I saw three airplanes in tandem flying in the same direction (NE to SW). When I looked around I saw several more older contrails to the east.
November 29, 2025 at 3:46 PM