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Caleb Scharf🌎 Profile
Caleb Scharf🌎

@caleb_scharf

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Following
5K
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Thinker, writer, sometimes both at the same time. Senior Scientist for Astrobiology @NASAAmes. Personal account, anything expressed here is my fault alone.

New York/Mountain View
Joined November 2010
Don't wanna be here? Send us removal request.
@caleb_scharf
Caleb Scharf🌎
3 years
Ok, so this is going down....
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@AnishA_Moonka
Anish Moonka
20 hours
That one neuron connects to about 7,000 others. Your brain has 86 billion of them. Do the math and you get somewhere around 100 trillion connections inside your head. More connections than stars in 1,500 galaxies. And each connection point is way more complicated than anyone
@NTFabiano
Nicholas Fabiano, MD
21 hours
This is 1 of 86 billion neurons in your brain.
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@caleb_scharf
Caleb Scharf🌎
16 days
Well, OK, I didn't see that coming... [you may fill in blanks as appropriate]
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@brianclegg
Brian Clegg
18 days
Interview: Astrobiologist Caleb Scharf @caleb_scharf tells us why he sees science as a contemplative discipline, the link between space exploration and evolution, and how AI can be involved in space. https://t.co/vf3WUCYeXg #spaceexploration #astrobiology #AI
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@Armen
Armen
20 days
@caleb_scharf on Mars: an alien observer might see Earth as messy biology - and the fourth planet as inhabited by machines. Through rovers and orbiters, life on Earth has already extended operational presence beyond the planet. From "The Giant Leap". @BasicBooks Full episode
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@caleb_scharf
Caleb Scharf🌎
19 days
That is a fantastic lenticular cloud (as @peachastro explains) - our planet serves up some wonderous things...
@peachastro
Damian Peach🔭🪐
20 days
I've been asked many times over the years if i've ever seen anything unusual or anomalous in the skies. Over my ~35yrs of serious observing i've spent thousands of hours outside gazing into the universe. Only one incident comes to mind that i'll never forget... I took this
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@caleb_scharf
Caleb Scharf🌎
19 days
New conversation with @Armen now up about ideas in my new book The Giant Leap (@BasicBooks) and plenty of other fun stuff too!
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@caleb_scharf
Caleb Scharf🌎
26 days
Wow! And (assuming colors are somewhat accurate) you can see some interesting spectral differences in the shadow!
@NOAASatellites
NOAA Satellites
26 days
You’ll want to see this without a shadow of a doubt! South Korea's GEO-KOMPSAT-2A geostationary satellite caught the #AnnularEclipse that passed over Antarctica this morning. 🌔 In this animation, you can see the moon's dark shadow quickly passing across the bottom left of the
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@caleb_scharf
Caleb Scharf🌎
26 days
Excited to share this preprint with the world. Introducing a new concept: The Interplanetary Habitable Zone via a mathematical framework and agent-based simulation to evaluate a whole system metric for space-faring species. I couldn't make it more @NASA if I tried 😀 (which I
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@miquai
Michael Wong
1 month
IT'S BOOK LAUNCH DAY 📖🚀✨ You can now find my first popular science book, Time's Second Arrow, wherever books are sold. Please help spread the word! https://t.co/12WDS4H6wJ
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wwnorton.com
A distinguished geoscientist and rising-star astrobiologist offer a stunning new theory upending 150 years of established science—and an inspiring new vision of our universe., Time's Second Arrow,...
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@caleb_scharf
Caleb Scharf🌎
1 month
We estimated that a cool brown dwarf could support computation (with high energy use efficiency) at around 10^19 times Earth's current total technological FLOPS
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@caleb_scharf
Caleb Scharf🌎
1 month
A fun bit of this paper was speculating on the use of sub-stellar objects to power computation. They're interesting because to get 90% thermodynamic efficiency from utilizing their emitted radiation you place receivers very close, so require far less material to enclose them
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@caleb_scharf
Caleb Scharf🌎
1 month
Recent moves towards space-based computing & data services reminded me of a study I did with @okw in 2024 where we deep-dived into a new concept, the "Computational Zone", a generalization of habitable zones. One part of this was a look at thermodynamic constraints on computing
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arxiv.org
Computation, if treated as a set of physical processes that act on information represented by states of matter, encompasses biological systems, digital systems, and other constructs, and may be a...
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@Sara_Imari
Sara Imari Walker
1 month
Currently hiring 1-2 postdocs to work on origins of life theory and experiment, assembly theory and life detection, with me and @leecronin, positions are mostly based at ASU but also some time could be spent at U. Glasgow, Apply here: https://t.co/cbE44B1Vn0 Please help us spread
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@caleb_scharf
Caleb Scharf🌎
1 month
You know it's a good science day when you get to write "boundedly rational utility maximizers" in an astrobiology research paper
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@caleb_scharf
Caleb Scharf🌎
1 month
Looks like the Arctic Circle is extending to NYC this weekend...
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@NASAJPL
NASA JPL
1 month
Perseverance just did something it’s never done before. On Dec. 8 and 10, 2025, the Mars rover completed drives planned by generative AI. The first-of-its-kind demonstration hints at a future of more efficient exploration and even more science. https://t.co/RbWmJXeVWi
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@caleb_scharf
Caleb Scharf🌎
2 months
Someone said to me today that I'm like Ted Lasso, but with a British accent and slightly grumpier. Honestly, I'm happy with that.
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@Armen
Armen
2 months
Information isn’t a modern invention. It’s older than humans. Genes → books → machines → data centers. One continuum. @caleb_scharf · Episode 306 · The Armen Show
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@caleb_scharf
Caleb Scharf🌎
2 months
Is it just me or is iOS’s new “Liquid Glass” design just profoundly awful? It feels like everything is rendered by an image processing system with edge detect set too high….sigh
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@caleb_scharf
Caleb Scharf🌎
2 months
A little chilly today on the Hudson River in NYC
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