Caleb Scharf
@calebscharf.bsky.social
Thinker, writer, sometimes both at the same time. Senior Scientist for Astrobiology at NASA Ames. Personal account, anything expressed here is my fault alone.
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Caleb Scharf
@calebscharf.bsky.social
· Oct 22
Is Colonizing Space the Next Stage of Human Evolution?
Life expanded from tidal pools to forests to great cities. The next step is space.
time.com
Fun little conversation with Jeffrey Kluger at TIME about The Giant Leap and the future of space exploration is now available. (spoiler: space is undoubtedly part of our future, but it could be a slow and tricky story): time.com/7326642/colo...
I can attest that this is a terrific book!
Do you like listening to audio books?
I'm excited to share that my first popular science book, Time's Second Arrow, will be available in audio format the same day the hardcover version hits bookshelves—February 10, 2026!
I'm excited to share that my first popular science book, Time's Second Arrow, will be available in audio format the same day the hardcover version hits bookshelves—February 10, 2026!
RBmedia | Time\'s Second Arrow
Listen to the audiobook Time\'s Second Arrow, written by Robert M Hazen;Michael L. Wong, narrated by Stephen Bowlby.
rbmediaglobal.com
January 15, 2026 at 8:16 PM
I can attest that this is a terrific book!
@nautil.us has this excellent series of "greatest revelations" from authors and others. I got to have my turn in talking about The Giant Leap and the things it revealed to me along the way... nautil.us/space-explor...
Space Exploration Speaks to the Core of Who We Are
Space Exploration Speaks to the Core of Who We Are: Astrobiologist Caleb Scharf’s 3 greatest revelations while The Giant Leap.
nautil.us
January 14, 2026 at 1:42 PM
@nautil.us has this excellent series of "greatest revelations" from authors and others. I got to have my turn in talking about The Giant Leap and the things it revealed to me along the way... nautil.us/space-explor...
Thrilled to see a great review of The Giant Leap over at the
@wsj.com ! “A scintillating tour of mankind’s explorations in space so far.” 😀 www.wsj.com/arts-culture...
@wsj.com ! “A scintillating tour of mankind’s explorations in space so far.” 😀 www.wsj.com/arts-culture...
‘The Giant Leap’ and ‘The Pale Blue Data Point’: Adventure Is Out There
Plus Jon Willis’s “The Pale Blue Data Point.”
www.wsj.com
January 10, 2026 at 3:10 PM
Thrilled to see a great review of The Giant Leap over at the
@wsj.com ! “A scintillating tour of mankind’s explorations in space so far.” 😀 www.wsj.com/arts-culture...
@wsj.com ! “A scintillating tour of mankind’s explorations in space so far.” 😀 www.wsj.com/arts-culture...
For a moment this phrasing gave me a nice vision of pigs sitting around discussing ancestry…
Pigs across the Pacific can trace their ancestry to Southeast Asian domestic pigs that accompanied early Austronesian-speaking groups as they island-hopped across the region, according to a new genomic study in Science. https://scim.ag/4aKOYtC
Genomic and morphometric evidence for Austronesian-mediated pig translocation in the Pacific
Several millennia of human-mediated translocation of non-native pig species (genus Sus) to the islands of Wallacea and Oceania have considerably altered local ecosystems. To investigate the timing and...
scim.ag
January 7, 2026 at 9:44 PM
For a moment this phrasing gave me a nice vision of pigs sitting around discussing ancestry…
New interview about The Giant Leap is now available - many thanks to Smithsonian Associates and Paul Vogelzang for a terrific conversation! podcasts.apple.com/us/podcast/t...
🎙️The Giant Leap: Is Space the Future of Life on Earth?
Podcast Episode · The Not Old - Better Show · 12/30/2025 · 39m
podcasts.apple.com
January 6, 2026 at 9:59 PM
New interview about The Giant Leap is now available - many thanks to Smithsonian Associates and Paul Vogelzang for a terrific conversation! podcasts.apple.com/us/podcast/t...
This is just incredible and lovely! Life in the abyss.
The deepest confirmed fish observation occurred at ~8,300 m. I know the shape behind it is another fish’s tail, but my brain insists it looks like the foreground fish is wearing a party hat. #deepsea #marinelife
www.nhm.ac.uk/discover/new...
www.nhm.ac.uk/discover/new...
January 5, 2026 at 9:44 PM
This is just incredible and lovely! Life in the abyss.
Reposted by Caleb Scharf
I haven’t stopped thinking about this frog since learning about it a few days ago, so now this knowledge is your problem too.
Meet the turtle frog (Myobatrachus gouldii) – a round burrow gremlin from Australia. It gets its name from looking like a turtle that lost its shell.
📸 Stephen Zozaya
Meet the turtle frog (Myobatrachus gouldii) – a round burrow gremlin from Australia. It gets its name from looking like a turtle that lost its shell.
📸 Stephen Zozaya
December 23, 2025 at 9:01 PM
I haven’t stopped thinking about this frog since learning about it a few days ago, so now this knowledge is your problem too.
Meet the turtle frog (Myobatrachus gouldii) – a round burrow gremlin from Australia. It gets its name from looking like a turtle that lost its shell.
📸 Stephen Zozaya
Meet the turtle frog (Myobatrachus gouldii) – a round burrow gremlin from Australia. It gets its name from looking like a turtle that lost its shell.
📸 Stephen Zozaya
Thanks @brianclegg.bsky.social for such a thoughtful review! Delighted that the book was of interest!
Review: The Giant Leap: @calebscharf.bsky.social **** - An invigorating mix of investigating the technology required to get humans into space and the idea that expanding into space is our evolutionary next step. popsciencebooks.blogspot.com/2025/12/the-... #bookreview #popularscience #spacetravel
The Giant Leap - Caleb Scharf ****
This is surely Caleb Scharf's most personal work - and certainly quite different from some of his earlier output, such as his excellent Grav...
popsciencebooks.blogspot.com
December 23, 2025 at 6:04 PM
Thanks @brianclegg.bsky.social for such a thoughtful review! Delighted that the book was of interest!
It's Friday, the holidays are upon us, what better time to read a book about the amazing enterprise of space exploration, and what it means for life on Earth!
December 19, 2025 at 2:55 PM
It's Friday, the holidays are upon us, what better time to read a book about the amazing enterprise of space exploration, and what it means for life on Earth!
Another conversation about my new book The Giant Leap (@BasicBooks) is now live! Space exploration is such a rich topic and it stirs so many viewpoints, it's very fascinating. convergingdialogues.substack.com/p/456-the-fu...
December 11, 2025 at 2:50 PM
Another conversation about my new book The Giant Leap (@BasicBooks) is now live! Space exploration is such a rich topic and it stirs so many viewpoints, it's very fascinating. convergingdialogues.substack.com/p/456-the-fu...
New conversation about my book The Giant Leap and quite a lot more - life in the universe, data, and the future of space w. Brad Carr: www.youtube.com/watch?v=g5Kd...
Caleb Scharf: Searching for Life in Space and the Shadow Biosphere
YouTube video by Brad Carr
www.youtube.com
November 29, 2025 at 2:40 PM
New conversation about my book The Giant Leap and quite a lot more - life in the universe, data, and the future of space w. Brad Carr: www.youtube.com/watch?v=g5Kd...
Reposted by Caleb Scharf
This image shows 3D, millimeter-thick, and cell-embeddable semiconducting hydrogel fibers.
These fibers can be used to construct interwoven living transistors that mimic real neuronal connections in the brain, redefining the boundary between technology and life. Learn more: https://scim.ag/4rqTOCj
These fibers can be used to construct interwoven living transistors that mimic real neuronal connections in the brain, redefining the boundary between technology and life. Learn more: https://scim.ag/4rqTOCj
November 20, 2025 at 7:05 PM
This image shows 3D, millimeter-thick, and cell-embeddable semiconducting hydrogel fibers.
These fibers can be used to construct interwoven living transistors that mimic real neuronal connections in the brain, redefining the boundary between technology and life. Learn more: https://scim.ag/4rqTOCj
These fibers can be used to construct interwoven living transistors that mimic real neuronal connections in the brain, redefining the boundary between technology and life. Learn more: https://scim.ag/4rqTOCj
I am puzzled by Bluesky: posts here seem to have a really hard time being seen by...well, anyone. Maybe I'm just losing my touch...
November 19, 2025 at 4:54 PM
I am puzzled by Bluesky: posts here seem to have a really hard time being seen by...well, anyone. Maybe I'm just losing my touch...
In my new book I explore the complex history of space exploration and its staggering impacts on human life and all life on Earth - for better or worse. To see what the future might bring we have to place space into context, as fundamental change to evolutionary possibilities.
November 19, 2025 at 2:25 PM
In my new book I explore the complex history of space exploration and its staggering impacts on human life and all life on Earth - for better or worse. To see what the future might bring we have to place space into context, as fundamental change to evolutionary possibilities.
A must listen…!
New podcast episode! 🪨🧪🤖🎙🖖
Dr. @anirudhprabhu.bsky.social joins me to discuss how we use machine learning trained on organic chemical data to detect the "whispers" of life—specifically photosynthetic life—in ancient rocks.
Dr. @anirudhprabhu.bsky.social joins me to discuss how we use machine learning trained on organic chemical data to detect the "whispers" of life—specifically photosynthetic life—in ancient rocks.
Episode 192: Whispers of Life in Ancient Rocks
Guest: Dr. Anirudh Prabhu
Mike brings aboard Dr. Anirudh Prabhu to discuss an exciting new study of theirs that uses machine learning trained on organic chemical data to detect the
soundcloud.com
November 18, 2025 at 3:23 PM
A must listen…!
ICYMI had a terrific time talking with @adamfrank4.bsky.social for this @bigthink.com interview about The Giant Leap (Basic Books) and the implications of space exploration for the near and far future of life on Earth. bigthink.com/13-8/the-nex...
The next great leap in evolution may lie beyond Earth
NASA’s Caleb Scharf talks with Big Think about how life’s story may be entering a new chapter — one that unfolds beyond Earth.
bigthink.com
November 17, 2025 at 2:50 PM
ICYMI had a terrific time talking with @adamfrank4.bsky.social for this @bigthink.com interview about The Giant Leap (Basic Books) and the implications of space exploration for the near and far future of life on Earth. bigthink.com/13-8/the-nex...
Reposted by Caleb Scharf
Marvelous new image of interstellar Comet 3I/ATLAS, taken by photographer Satoru Murata before dawn this morning.
On the right you can also see galaxy NGC 4691. There should be a lot more pictures coming in soon. 🧪🔭
www.facebook.com/groups/22700...
On the right you can also see galaxy NGC 4691. There should be a lot more pictures coming in soon. 🧪🔭
www.facebook.com/groups/22700...
November 16, 2025 at 9:20 PM
Marvelous new image of interstellar Comet 3I/ATLAS, taken by photographer Satoru Murata before dawn this morning.
On the right you can also see galaxy NGC 4691. There should be a lot more pictures coming in soon. 🧪🔭
www.facebook.com/groups/22700...
On the right you can also see galaxy NGC 4691. There should be a lot more pictures coming in soon. 🧪🔭
www.facebook.com/groups/22700...
Great news!
🛰️🛰️ The twins are talking!
We have successfully established contact with both ESCAPADE spacecraft, 💙 Blue and 💛 Gold, following launch on Blue Origin's New Glenn rocket today.
We're on our way to Mars to enable NASA and UC Berkeley Space Sciences Lab to study the Martian magnetosphere!
We have successfully established contact with both ESCAPADE spacecraft, 💙 Blue and 💛 Gold, following launch on Blue Origin's New Glenn rocket today.
We're on our way to Mars to enable NASA and UC Berkeley Space Sciences Lab to study the Martian magnetosphere!
November 14, 2025 at 7:39 PM
Great news!
Reposted by Caleb Scharf
ICYMI: Last week, @calebscharf.bsky.social asked us to imagine space exploration as life’s next "Giant Leap" during our most recent #NeighborhoodLecture.
We pulled out 5 of the most mind-blowing ideas and posted the full recording here.👇🤯
carnegiescience.edu/five-ways-ca...
We pulled out 5 of the most mind-blowing ideas and posted the full recording here.👇🤯
carnegiescience.edu/five-ways-ca...
Five ways Caleb Scharf’s "The Giant Leap" might rewire how you think about life
At a recent Neighborhood Lecture, NASA astrobiologist Caleb Scharf invited audiences to see space exploration not as a race to new worlds, but as biology in motion—life extending its reach beyond Eart...
carnegiescience.edu
November 13, 2025 at 4:58 PM
ICYMI: Last week, @calebscharf.bsky.social asked us to imagine space exploration as life’s next "Giant Leap" during our most recent #NeighborhoodLecture.
We pulled out 5 of the most mind-blowing ideas and posted the full recording here.👇🤯
carnegiescience.edu/five-ways-ca...
We pulled out 5 of the most mind-blowing ideas and posted the full recording here.👇🤯
carnegiescience.edu/five-ways-ca...
New video! My full presentation about The Giant Leap to a live audience at @carnegiescience.bsky.social is now online! We grappled with science, philosophy, and the meaning of life! www.youtube.com/watch?v=cG1V...
The Giant Leap
YouTube video by Carnegie Science
www.youtube.com
November 12, 2025 at 3:43 PM
New video! My full presentation about The Giant Leap to a live audience at @carnegiescience.bsky.social is now online! We grappled with science, philosophy, and the meaning of life! www.youtube.com/watch?v=cG1V...
Reposted by Caleb Scharf
Now on @sciam.bsky.social: In his new book, The Giant Leap, NASA astrobiologist @calebscharf.bsky.social says the fate of life on Earth may hinge on leaving our planet behind.
www.scientificamerican.com/article/is-s...
www.scientificamerican.com/article/is-s...
Is Space the Place for Earth’s Next Evolutionary Leap?
In a new book, NASA astrobiologist Caleb Scharf says the fate of life on Earth may hinge on leaving our planet behind
www.scientificamerican.com
November 10, 2025 at 3:24 PM
Now on @sciam.bsky.social: In his new book, The Giant Leap, NASA astrobiologist @calebscharf.bsky.social says the fate of life on Earth may hinge on leaving our planet behind.
www.scientificamerican.com/article/is-s...
www.scientificamerican.com/article/is-s...
Simultaneously beautiful and the stuff of small human nightmares...
A pitch-black cave in the Balkans is home to what appears to be the world’s largest spider web, which researchers say is a singular work of cooperation by two usually-hostile species of spider. www.nytimes.com/2025/11/08/s...
November 9, 2025 at 9:34 PM
Simultaneously beautiful and the stuff of small human nightmares...
A topic that has come up in interviews and presentations for my new book The Giant Leap is reconceptualizing the notion of habitability for a planetary system (like ours) where life disperses from its point of origin. I use this graphic to help discuss: [1/n]
November 9, 2025 at 9:22 PM
A topic that has come up in interviews and presentations for my new book The Giant Leap is reconceptualizing the notion of habitability for a planetary system (like ours) where life disperses from its point of origin. I use this graphic to help discuss: [1/n]
Indeed…definitely the B Ark
Speaking as a spacecraft engineer, the thing that gets me about Loeb's interpretations is that his alien engineers are insultingly incompetent.
RCS thruster plumes visible from the other side of the solar system, making no difference in the trajectory?!
And 'Oumuamua was a *terrible* solar sail.
RCS thruster plumes visible from the other side of the solar system, making no difference in the trajectory?!
And 'Oumuamua was a *terrible* solar sail.
November 8, 2025 at 8:22 PM
Indeed…definitely the B Ark
A new, fun conversation with Lyn Ware Peek at Cool Science Radio for NPR's KPCW all about space exploration and my new book The Giant Leap: www.kpcw.org/show/cool-sc...
How life evolves beyond Earth
Astrobiologist Caleb Scharf discusses his new book, "The Giant Leap: Why Space Is the Next Frontier in the Evolution of Life," exploring how humanity’s expansion into space represents a profound new p...
www.kpcw.org
November 8, 2025 at 7:38 PM
A new, fun conversation with Lyn Ware Peek at Cool Science Radio for NPR's KPCW all about space exploration and my new book The Giant Leap: www.kpcw.org/show/cool-sc...