Greg Gilbert
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gjgilbert.bsky.social
Greg Gilbert
@gjgilbert.bsky.social
Astronomer @Caltech
Reposted by Greg Gilbert
JESUS, MARY, AND JOSEPH! This gave me old Google back! It killed the AI results dead!
August 17, 2025 at 11:03 PM
Reposted by Greg Gilbert
Kepler mission: smaller stars have more short-period, small #exoplanets.

Theory: the smallest stars won’t have enough disk material to make small planets so there must be a turnover.

Kepler+K2: We have found a turnover!

Check out our newest Scaling K2 paper: arxiv.org/abs/2508.05734

🧵 1/9
🔭🧪☄️
Scaling K2 VIII: Short-Period Sub-Neptune Occurrence Rates Peak Around Early-Type M Dwarfs
We uniformly combined data from the NASA Kepler and K2 missions to compute planet occurrence rates across the entire FGK and M dwarf stellar range. The K2 mission, driven by targets selected by guest ...
arxiv.org
August 11, 2025 at 1:01 AM
Want to learn about the relationship between planet size and orbital eccentricity? Read this thread! 🧪 🔭 🪐
July 17, 2025 at 8:28 PM
Reposted by Greg Gilbert
Astronomers may have just discovered the third interstellar object passing through the Solar System!

ESA’s Planetary Defenders are observing the object, provisionally known as #A11pl3Z, right now using telescopes around the world.
July 2, 2025 at 8:23 AM
Reposted by Greg Gilbert
First the rumour was a 20% budget cut. Then, 50%. Now the president's NASA budget is out and it's a 68% cut to astrophysics ($1.5B to $487M).

Even if this gets reversed in four years, we will *never* recover the missions, partners, people who will be gone.

www.washingtonpost.com/science/2025...
Massive cuts to NASA science proposed in early White House budget plan
The preliminary version of President Donald Trump’s budget proposal to Congress, known as a “passback,” would cut the agency’s science budget funding nearly in half.
www.washingtonpost.com
April 11, 2025 at 2:54 PM
Thanks for the write-up, @dtstarkid.bsky.social
🚨Breaking exoplanet discovery🚨UCLA astronomers uncover that Gas giants form via distinctly different pathways from smaller planets 🧵
March 8, 2025 at 7:13 PM
Reposted by Greg Gilbert
I’m working on a piece about funding basic science and if you’ve never explored spinoff.nasa.gov, I would really encourage you to do so. Even though I’ve been doing this for 20 years, it really is humbling and informative to see the ways in which space science works its way into our daily lives.
Home | NASA Spinoff
spinoff.nasa.gov
March 6, 2025 at 2:47 PM
Reposted by Greg Gilbert
But more accurately...

Physics major → existential crisis → the improv years (TM) → teaching high school → start grad school → get sick → in-and-out of the hospital for 3 years → finish grad school → astrophysics postdoc

Just a reminder that winding paths can look straight when zoomed out
If you went to college...
1. what was your career goal when you started?
2. your initial major?
3. if you changed majors, what did you change to?
4. what do you do now, professionally?

1. Physics research
2. Physics
3. Physics
4. (Astro)physics research
if you went to college
1. what was your career goal when you started?
2. your initial major?
3. if you changed majors, what did you change to?
4. what do you do now, professionally?

1. Politician (lol)
2. Physics (changed my mind from polisci before we had to declare)
3. Physics
4. Applied physics
January 22, 2025 at 7:25 PM
If you went to college...
1. what was your career goal when you started?
2. your initial major?
3. if you changed majors, what did you change to?
4. what do you do now, professionally?

1. Physics research
2. Physics
3. Physics
4. (Astro)physics research
if you went to college
1. what was your career goal when you started?
2. your initial major?
3. if you changed majors, what did you change to?
4. what do you do now, professionally?

1. Politician (lol)
2. Physics (changed my mind from polisci before we had to declare)
3. Physics
4. Applied physics
if you went to college
1. what was your career goal when you started?
2. your initial major?
3. if you changed majors, what did you change to?
4. what do you do now, professionally?

1. Science research
2. Biotechnology
3. Physics and maths
4. Astronomer
January 22, 2025 at 7:18 PM
Reposted by Greg Gilbert
The ESA #Gaia mission has delivered the best Milky Way maps to date and taken its last starlight before spacecraft retirement 🔭

www.esa.int/Science_Expl...
January 15, 2025 at 12:03 PM
Reposted by Greg Gilbert
Astronomy friends, don't forget to give MAST @mast-news.bsky.social a follow.
January 10, 2025 at 12:37 PM
Reposted by Greg Gilbert
My friend @gjgilbert.bsky.social has likened building a full colony on Mars to getting a flat tire and rebuilding your entire car from scratch, including mining the ore for all the metals yourself. We're so much better off fixing the problems here, where there's oxygen and lakes and normal sun.
The temperature on Mars gets down to like -250 degrees at night because it has no atmosphere. So no trapped heat. Also no air. And no water. And no trees. And no food. And no structures, for shelter. And no possible way for humans to survive. Anyway here's the world's richest man with some thoughts:
December 31, 2024 at 3:31 AM
Every university physics building in America looks like a rejected GoldenEye level on the inside. Immaculate vibes, no notes.
April 18, 2024 at 7:38 PM
My favorite 2017 eclipse moment --

I watched from a farm in rural Missouri. As the twilight of totality set in, the crickets chirped and the barn animals fell asleep. Two and a half minutes later, the sky brightened and the geese began angrily honking for their breakfast. #goosenap2017
April 8, 2024 at 4:50 PM
Observing on KPF tonight. AKA Friday Night Lights: Clear skies, full charts, can't snooze.
November 25, 2023 at 11:34 AM