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Dagomar Degroot

@dagomardegroot.bsky.social

2.3K followers 100 following 84 posts

Professor of environmental history at Georgetown University. Creator, The Climate Chronicles podcast. Author of the new book, "Ripples on the Cosmic Ocean." Interested in all things climate change, outer space, existential risk, and past for present.

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Dagomar Degroot @dagomardegroot.bsky.social · Aug 1

In my forthcoming book, "Ripples on the Cosmic Ocean," I show that what happens in space matters on Earth—and what happens on Earth increasingly matters in space. In this interview with Harvard University Press, I reflect on the implications of that idea. #EnvHist www.hup.harvard.edu/features/the...

The Final Frontier is Closer Than You Think — Harvard University Press

How cosmic forces have shaped—and continue to shape—our world. We are creatures of the cosmos, whether we realize it or not, argues environmental historian Dagomar Degroot. His captivating new book “R...

www.hup.harvard.edu

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Bill McKibben @billmckibben.bsky.social · 4d

Hmm. With solar energy, the big explosions take place 93 million miles away

The New York Times @nytimes.com · 4d

A fireball lit up the sky across the Los Angeles area on Thursday night after an explosion at a Chevron refinery in El Segundo, alarming nearby residents who said it felt like an earthquake. The cause of the explosion was not clear. No injuries were reported. nyti.ms/42pPCaW

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David Grinspoon @drfunkyspoon.bsky.social · 3d

In grad school in the 80s we were taught that most other stars *should* have planets, which we’ll hopefully be able to observe some day, since the formation of planets seems to be a normal byproduct of star formation.
This was right!

But we were also taught that (2)…

Dr. Jessie Christiansen @aussiastronomer.bsky.social · 5d

This week (!) is the 30th anniversary of the announcement of 51 Pegasi b, the first exoplanet found orbiting a star like our Sun - since then, we've found over 6,000!

To celebrate, @alexwitze.bsky.social and @nature.com collected some astronomers' favourite planets:

www.nature.com/articles/d41...

These alien planets are astronomers’ favourites: here’s why

Space scientists look back on 30 years of exoplanet discoveries — from rows of massive ‘super-Earths‘ to worlds with perfectly synchronized orbits.

www.nature.com

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Patrick McCray @patrickmccray.bsky.social · 4d

4 October 1957...the USSR launches Sputnik I.

Teams of citizen scientists around the planet - all part of the Smithsonian's Operation Moonwatch - turn out and successfully spot and track it.

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Michael Wong @miquai.bsky.social · 6d

“There is no longer a path for someone to come work at NASA when they grow up.” 😢

Thousands of NASA employees to bid farewell to the NASA they knew

As October begins, thousands of longtime NASA employees are leaving the agency. 4000+ will exit by January 9, 2026, changing NASA forever.

bigthink.com

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Dagomar Degroot @dagomardegroot.bsky.social · 6d

Talk about a life well lived. An inspiration. www.nytimes.com/2025/10/01/o...

Jane Goodall, Eminent Primatologist Who Chronicled the Lives of Chimps, Dies at 91

www.nytimes.com

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Dagomar Degroot @dagomardegroot.bsky.social · 8d

It's finally in my hands! @harvardpress.bsky.social did such a wonderful job with the jacket. It's available for preorder, and will ship (to anyone in the US or Canada) on October 28th. #EnvHist #Astronomy #Space

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Dagomar Degroot @dagomardegroot.bsky.social · 10d

Me too!

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NiCHE Canada @nichecanada.bsky.social · 10d

Applicants Sought for Editor of Environmental History
- @envirohistory.bsky.social

@aseh.bsky.social & @foresthistory.bsky.social seek applicants to serve as Editor(s) and a new institutional home for the journal Environmental History for a 5-year term.

niche-canada.org/2025/09/27/a...

#envhist

Applicants Sought for Editor of Environmental History

The American Society for Environmental History and the Forest History Society seek applicants to serve as Editor(s) and a new institutional home for the journal Environmental History for a five-year t...

niche-canada.org

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Dagomar Degroot @dagomardegroot.bsky.social · 10d

Great point.

Dagomar Degroot @dagomardegroot.bsky.social · 10d

That's probably from most to least likely.

It's troubling - to say the least - that hundreds and hundreds of billions are flowing towards an industry that has bet its future, and perhaps the future of humanity, on what may be an unlikely, best-case outcome. #AI

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Dagomar Degroot @dagomardegroot.bsky.social · 10d

I see 4 possibilities:

1. The tech plateaus, the bubble bursts.
2. The tech improves, millions are jobless, they rise up, the industry dies.
3. An unaligned AGI emerges, improves itself, and threatens humanity.
4. A golden age of human wealth and health, powered by AI.

www.wsj.com/tech/ai/ai-b...

Spending on AI Is at Epic Levels. Will It Ever Pay Off?

Tech companies are pouring hundreds of billions into data centers, taking on heavy debt, but current revenue is relatively tiny. Critics warn of a new dot-com bubble.

www.wsj.com

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Dagomar Degroot @dagomardegroot.bsky.social · 12d

Here’s something I wrote that touches on mistakes/failures: niche-canada.org/2022/08/30/w...

Writing About Climate Change, Whaling, and Conflict in the Seventeenth Century Arctic

Dagomar Degroot recounts the journey that led to his recent article "Blood and Bone, Tears and Oil"

niche-canada.org

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Dagomar Degroot @dagomardegroot.bsky.social · 13d

Ha! Amazing. Obviously we timed it on purpose.

Dagomar Degroot @dagomardegroot.bsky.social · 13d

A special honor to be back at #NASA HQ last week. Drawing on the research in my new book, Ripples on the Cosmic Ocean (out on October 28!), I traced some ways in which the search for life on other worlds is helping us understand - and, hopefully, preserve - the future of life on Earth. #Astrobiology

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Dagomar Degroot @dagomardegroot.bsky.social · 13d

Sure. Will be on the lookout for more scorpions.

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Dagomar Degroot @dagomardegroot.bsky.social · 13d

These posts may have single-handedly convinced me to stay on BlueSky. Thank you.

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Dagomar Degroot @dagomardegroot.bsky.social · 13d

Bowheads have been my jam but I might diversify into sperm whales after this.

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Dagomar Degroot @dagomardegroot.bsky.social · 13d

Nobody’s better at social media than @rebeccarhelm.bsky.social! This footage has been my holy grail since I was a kid…

Rebecca R Helm @rebeccarhelm.bsky.social · 13d

I get that the news cycle is packed right now, but I just heard from a colleague at the Smithsonian that this is fully a GIANT SQUID BEING EATEN BY A SPERM WHALE and it’s possibly the first ever confirmed video according to a friend at NOAA

10 YEAR OLD ME IS LOSING HER MIND (a thread 🧵)

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Dagomar Degroot @dagomardegroot.bsky.social · 13d

I'm often skeptical of big histories that focus on disaster. Yet Goliath's Curse (by @lukekemp.bsky.social) is masterful. It explores the causes & consequences of collapse as a historical phenomenon. It's clear, insightful, harrowing - but ultimately hopeful. #EnvHist www.amazon.com/Goliaths-Cur...

Goliath's Curse: The History and Future of Societal Collapse

Amazon.com: Goliath's Curse: The History and Future of Societal Collapse: 9780593321355: Kemp, Luke: Books

www.amazon.com

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Rebecca R Helm @rebeccarhelm.bsky.social · 14d

The UN is a bit like the foundation of an old house. Expensive to maintain and costly to repair but WOW you do not want to break it. So much of our modern world is held together by the invisible work of multilateral diplomacy. I shudder to think what the world would be like without it

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Zeke Hausfather @hausfath.bsky.social · 14d

In a UN speech today, President Trump said that "all of these [climate] predictions were wrong".

Back in 2019 I led a research effort to digitize old climate model projections and assess how well they did. Turns out they got future warming pretty spot on!

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Dagomar Degroot @dagomardegroot.bsky.social · 16d

A strong response to a thought-provoking article. In my view, some form of geoengineering *will* be implemented sometime in the next few decades. The costs will seem low, and the damage inflicted by #ClimateChange will make the temptation too great to resist. There are many risks, unfortunately....

Ben Sanderson @benmsanderson.bsky.social · 16d

Sorry, but disagree with @hausfath.bsky.social here. You open Pandora's box, you ain't closing it again. We've already seen with Paris that well intentioned international agreements do not translate into physical reality and SRM governance is a much harder problem. Zero is the only safe level. /1

Zeke Hausfather @hausfath.bsky.social · 16d

I have a new @nytimes.com guest essay w/ @davidkeith.bsky.social about sunlight reflection. We note its not a solution for climate change and at best a band aid to treat systems, and suggest if its ever done it should only be to replace the cooling from air pollution today:

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David Grinspoon @drfunkyspoon.bsky.social · 25d

ASTROBIOLOGY AND…
Life, The Cosmos & the Human Story

Short talks by all the NASA/Library of Congress Astrobiology Chairs

DC area folks - This will be an amazing event next Wednesday (9/17) afternoon at NASA HQ - open to the public, not live-streamed. Attendance limited. Please RSVP & attend!
🧪

Astrobiology And…
Life, the Cosmos, the Human Story

Wednesday, September 17, 2025
3-5pm EDT
Please RSVP here to attend
https://docs.google.com/forms/d/e/1FAIpQLSeLMcW07jemIFTGOEoaeQzYO6f8PmZLvGChi28QAVqKHJ3WzQ/viewform

NASA Headquarters
300 Hidden Figures Way SW, Washington, D.C.
Webb Auditorium

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Dana Nuccitelli @dananuccitelli.bsky.social · 22d

We're halfway between the IPCC 6th and 7th Assessment Reports, and an international team of 61 scientists updated some of the key metrics used in the reports. As I wrote for @climateconnections.bsky.social, the findings were pretty bleak, but there are some glimmers of hope 🧵 (1/6)

Yale Climate Connections @climateconnections.bsky.social · 22d

🔥 The world’s top climate scientists have found that global warming is accelerating. Oceans are rising faster than ever, and the 1.5°C target is slipping away, but there’s still a narrow path forward. #ClimateAction

Climate change is accelerating, scientists find in ‘grim’ report » Yale Climate Connections

They warn that humanity is just three years from overshooting the Paris Agreement’s 1.5°C target, with seas rising faster than ever. But the report also contains a little bit of good news.

yaleclimateconnections.org

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David Grinspoon @drfunkyspoon.bsky.social · 27d

LIFE ON MARS??!!
I know you’re wary of overhyped claims of ET life. & we need to be cautious. As Sagan used to remind us, life should be the hypothesis of last resort. But this is one to watch. Legitimately a “potential biosignature” which demands follow up.
🧪
www.washingtonpost.com/technology/2...

NASA discovers ‘clearest sign of life that we’ve ever found on Mars’

Detailed analysis of images of speckled rocks found by NASA’s Perseverance rover has found a “potential biosignature.”

www.washingtonpost.com

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