Dr. Fred J. Calef III

Fifty three years ago, in December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon exploring the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead. This snapshot from another world was taken by Cernan as he and Schmitt roamed the lunar valley's floor. The image shows Schmitt next to the lunar rover parked at the southeast rim of Shorty Crater. That location is near the spot where geologist Schmitt discovered orange lunar soil. The Apollo 17 crew returned with 110 kilograms of rock and soil samples, more than was returned from any of the other lunar landing sites. And for now, Cernan and Schmitt are the last to walk on the Moon.

🔭 Apollo 17 at Shorty Crater

Apollo 17 Crew, NASA

apod.nasa.gov/apod/ap25120...

What our missing ocean float revealed about Antartica’s melting glaciers Our ocean float spent years adrift in the Antarctic ocean and beneath massive ice shelves. What it found will help us estimate global sea-level rise.

🌊 Serendipity often drives science forward.

A “lost” Argo float drifted under Antarctica’s ice shelves and resurfaced with a warning: warm water is creeping under major glaciers like Denman and Totten.

What’s at risk? Up to 5 m of global sea-level rise.

theconversation.com/what-our-mis...

Last night still doesn't feel real. Visible aurora from 35° N over my backyard city lights. Insane!

Hegseth lied after leaking classified information on Signal. He also lied after the second boat strike.

He is unfit to serve. Hegseth must resign.

Rover track marks wander off into the distance, occasionally trampling across widely-spaced low Martian sand ripples across the rocky slope. One of the rover's wheels is visible bottom-right.

Orientation screenshot showing raw images projected against the inside of a sphere.

My projected processed version.

NASA Mars Perseverance Rover at Jezero crater Sol 1,703 (4th December, 2025)

Another view from the look-around
1. Processed raw.
2. Orientation screenshot from Marslife
3. Projected processed raw

NavCam-left
Site 82 / 2714
📷 Credits: NASA / JPL-Caltech / MSSS / Martian-Observer

linear cross section showing chunk of a colonial skeleton in a wall stone layer

linear cross section showing chunk of a colonial skeleton in a wall stone layer

MORE urban geology of DC! #fossilfriday I think more bryozoan ? or coral? Paleozoic feel.

For those who will be attending, please think very hard about what you intend to do if you encounter people getting detained. I'm not advocating for any particular action, but the best time to consider how you want to respond is before you're in the moment.

Star Wars’ original theatrical cut returns to theaters in 2027 See Han shoot first.

Omg

www.theverge.com/news/839434/...

If you're attending #AGU, I'd at the very least get a loud whistle and have it at the ready at all times.

That one fact means it’s all war theatre. They didn’t protect US citizens by killing those potential drug smugglers, they just enjoyed acting tough by murdering people who were essentially defenseless from their heinous attack. They all need to go to jail.

Pink Fairy Armadillos Have a Weird Double Skin Not Seen in Any Other Mammal Pink fairy armadillos evolved a unique double skin millions of years ago as they moved underground in response to a drying climate

There's a nice Scientific American article that discusses the unique physiology of their armor plates, which don't harden until adulthood, and play a key role in their thermoregulation.

It's behind a paywall, unfortunately.

Pink fairy armadillos (or pichiciegos) are found in the warm sandy plains of Argentina. These armadillos prefer to burrow in very dry soil. They leave their burrows if it is moistened by rainfall. These animals often burrow near anthills, so that they can be close to their food source. The pink fairy armadillo generally lives by itself. The animals stay in their burrrows during the day and feed at night. They are remarkable diggers. The pink fairy armadillo is the smallest member of the armadillo family, measuring only about five to six inches in length. It is also the only armadillo in which the dorsal shell is almost separate from the body. Baby armadillos resemble their parents, but their shells do not completely harden until they are full grown From Cliff at Wikimedia, but previously on Flickr.

The pink fairy armadillo (Chlamyphorus truncatus) is just this little guy.

The smallest of the armadillo family, they live in the deserts of Argentina, burrowing through dry sand with giant paws, almost as fast as a fish can swim.

The armor is greatly reduced, but the pink fairy has THICK FUR.

A space image with stars and a few planet illustrations in the background, with gold balloons and a birthday hat in the foreground with the text NASA EXOPLANET SCIENCE INSTITUTE and NASA Exoplanet Archive. The graphic is to celebrate the 14 years of the NASA Exoplanet Archive.

Happy 14 orbits to the NASA #Exoplanet Archive!

Launched on December 5, 2011, the archive has become THE destination for published exoplanet parameters. I've been using it since its inception, and now I'm lucky enough to get to help maintain it and make it better for all astronomers!

I Left the CDC 100 Days Ago. My Worst Fears About the Agency Are Coming True "Things have not improved," writes Dr. Debra Houry. "They have worsened. And Congress has still failed to act."

"I did not resign to make a symbolic point," writes Dr. Debra Houry, former chief medical officer of the CDC. "I resigned because staying silent would have made me complicit." 🛟 🧪 time.com/7338714/dr-d...

I hope @agu.org is going to speak to #AGU25 attendee safety, and acknowledge the potential increased threat to some attendees based on what some morally corrupt, bigoted CPB/ICE agent thinks about how they look or where they're from.

Allow people to cancel & refund their registration $.

WCK’s Mohammad is at what will be our newest Field Kitchen in North Gaza, where teams are working hard to expand support for families in the region. Once completed, the kitchen will provide hot meals, water from a new desalination system, and fresh bread from a mobile bakery truck. #ChefsForGaza

Bad framing: ACIP voted to scrap the universal hepatitis B vaccine recommendation for newborns.

Accurate framing: Anti-vax conspiracy theorists appointed to ACIP by Robert Kennedy Jr., who made a fortune as an anti-vax profiteer, voted to expose babies to a preventable, incurable, deadly illness.

Surface of an iceberg, with some pointy shapes and golden reflections. In the back are some golden sparkles, of the sun catching the froth on the breaking waves.

Close-up of some ice at sunrise. Miss the ice...

#Iceland Nov 2025

500+ from JPL last month. 🤬

A war criminal without a war It's just murder.

"When there’s no war, you aren’t committing war crimes when you kill people indiscriminately. You’re just a straight-up murderer."

A telescopic image of the Sun, which looks like an orange circle with several groups of black sunspots.

Great sunspots today. 🔭

A fascinating, clear and understandable talk by Dame Jocelyn Bell Burnell explaining how technological developments (for example CMOS cameras, leading to much shorter exposure times) have led to the realisation that many more objects in the universe than we realised are variable.

University Of Southern California Layoffs Now Total More Than 900 Since July, the University of Southern California has laid off more than 900 employees, as it attempts to reduce a deficit that exceeded $200 million in Fiscal Year 2025.

I had somehow missed that USC fired more than 900 (!) people

www.forbes.com/sites/michae...

A view of the headshield of Megalograptus, preserved as reddish-brown cuticle on a pale grey rock. The headshield is generally equilateral in shape, with a rounded front bearing small spiny projections. A pair of round eyes are also located at the front of the head. The surface of the headshield is curved in dense, pustule-like scales.

A fossil of the second appendage of Megalograptus, preserved as dark cuticle on a light grey rock. The appendage is short with robust spines coming off of it.

A view of the body segments of Megalograptus, preserved as dark cuticle on pale grey rock. Four body segments are present, again preserving small, pustule-like scales.

One of the earliest large predatory eurypterids, Megalograptus, for #FossilFriday. Megalograptus is known from abundant - and very unusual - material from the Ordovician of #Ohio, affording an important insight into the morphology of this rather bizarre species. ⚒️🧪

Rep. Grijalva is doing what a Member of Congress should do: standing up for her constituents.

Pepper spraying an elected official doing her job is outrageous and does nothing to make Arizona communities safer.

NEW— DC Metropolitan Police just shared a tiny bit more body cam footage from the March US Institute of Peace raid in response to my FOIA lawsuit w/ @rcfp.org

One clip shows USIP President George Moose being escorted out.

Moose: You know we're gonna see you all in court.
MPD: Yea we figured that.

It’s straight up murder directed by our criminal President and all his Secretary toadies and advisors.

Yobana Rusnya!!! 🤬

I think anyone listening to the administrations statements would be hard pressed to find actual truth in anything they say.

The December issue of GSA Today is full of innovative ideas in the geosciences!

• Learn about how NASA's SWOT satellite is revolutionizing fluvial geomorphology.
• Tag along on a college hydrogeology field course.
• And so much more! 🌎

Read the newest issue here: geosociety.co/GSATDec25

#GSAToday