Daniel Pomarède

An aerial image of Mars' south pole. Text reads: Mars' south pole lacks lake beneath the ice. Sharad, the Shallow Radar sounder on NASA's Mars Reconnaissance Orbiter, recorded only a faint signal where MARSIS, the low-frequency radar on the European Space Agency's Mars Express spacecraft, found a highly radar-reflective surface under the ice in 2018, which that team interpreted to be due to the presence of liquid water.

A new study published in Geophysical Research Letters casts doubt on a 2018 discovery of a briny lake potentially lurking beneath Mars’s south polar cap. 🧪 🔭

Read the full story: buff.ly/JRpyeku

A radio dish antenna pointing upwards in the sky in a field. In the distance are trees. Above it, fluffy rain filled clouds make a dramatic sky.

Yesterday, when I was leaving work I had to pull over and grab this photo — cause the clouds above one of the old radio telescopes at work looked really good. Puffy blobs sinking under their weight.

This is Remus 📡

I’ve stretched the image a little by increasing contrast, and foreground shadows.

L'incroyable parcours de Madeleine Brès, première Française à obtenir son diplôme de médecine

Si c'est votre anniversaire aujourd'hui, vous le partagez avec Madeleine Brès, première Française à obtenir son diplôme de médecine

(Et bon anniversaire ! 🎉)

For many, nothing evokes fall more than fallen leaves. In this view of NGC 6334, glowing pockets of dust and gas in the nebula resemble leaves that have been picked up by a wind gust. This region is actually home to strong winds blowing from the young stars that have formed there. This image contains X-ray data from Chandra (blue, green, and yellow) that shows the effects of these winds, which have been combined with infrared data from the now-retired Spitzer Space Telescope (red, brown), which shows the dust and gas that fuels the growing stars. Credit: X-ray: NASA/SAO/CXC; Infrared: NASA/JPL/CalTech/Spitzer; Image Processing: NASA/CXC/SAO/J. Schmidt

Born after a violent explosion of a star, this cosmic gourd is the supernova remnant G272.2-03.2. X-ray observations (orange and magenta) from Chandra provide evidence that G272 is the result of a Type Ia supernova explosion, where a white dwarf star pulls material from a companion star until it triggers a thermonuclear explosion and obliterates the star. The inside of the “pumpkin” is superheated gas that is filling the space cleared out by the explosion as it moves outward. Credit: X-ray: NASA/CXC/SA0; Optical: NOIRLab/DECaPS2; Image Processing: NASA/CXC/SAO/L. Frattare

Multiple telescopes teamed up to capture an image that looks like a cozy sweater with fuzzy arms. X-rays from Chandra and ESA’s XMM-Newton (purple), optical light data from Hubble and the Very Large Telescope in Chile (orange, red, and violet), and an optical image from astrophotographer Bob Fera (deep blue) combine to reveal R Aquarii. Nestled within the cozy ‘body’ of R Aquarii is a pair of stars where a white dwarf is pulling material from a much larger red giant companion. When enough material accumulates on the surface of the white dwarf, it triggers an outburst that sends a jet out into space. Over time, these jets twist and loop around each other weaving the structure seen today. Credit: X-ray: NASA/CXC/SAO; ESA/XMM-Newton; Optical HST: NASA/ESA/STScI; Optical Ground: Deep Space Remote observatories/B. Fera; ESO/VLT; Image Processing: NASA/CXC/SAO/L. Frattare

A cornucopia is a horn-shaped basket that traditionally carries fruits and vegetables. There is nothing edible in this pair of galactic cornucopias but there are a bounty of stars, dust, and other ingredients than make up these two spiral galaxies, known as NGC 2207 (right) and IC 2163 (left), that we see face-on. This view of NGC 2207 and IC 2163 takes a James Webb infrared image (white, gray, and red) and adds the X-ray view from Chandra (blue). Together, it is quite an eye-catching result. Credit: X-ray: NASA/CXC/SAO; Infrared: NASA/ESA/CSA/STScI/Webb; Image Processing: NASA/CXC/SAO/L. Frattare

Chandra's Fall Collection 🍂

A quartet of images that invoke themes associated with autumn

1. NGC 6334 nebula: Cosmic leaves blowing
2. SNR G272.2-03.2: The Space Pumpkin
3. R Aquarii: A cosmic sweater
4. NGC 2207 and IC 2163: A pair of galactic cornucucopia

chandra.harvard.edu/photo/2025/f... 🔭🧪

Resolving the flat-spectrum conundrum: clumpy aerosol distributions in sub-Neptune atmospheres Transmission spectroscopy of sub-Neptunes was expected to reveal their compositions and hence origins, yet many show flat near- to mid-infrared spectra. Such spectra can be explained either by metal d...

If your planet's not too big, and your transit spectrum is flatter than you'd think, your aerosols might be clumpy.
Owen+ arxiv.org/abs/2511.19013
🧪🔭🪐 #exoplanets

Venus is the Best Place in the Solar System to Establish a Human Settlement (2003) The story of spaceflight told through missions and programs that did not happen - that is, the great majority of them.

Here's a thing I wrote about Geoffrey Landis's Cenus sky cities.

spaceflighthistory.blogspot.com/2020/08/venu...

Et demain, on consacrera notre émission à Archimède, le grand savant antique !
Calcul de Pi, poussée d'Archimède... Nous verrons comment son travail a irrigué les mathématiques et l'ingénierie 📐
Ce sera à 16h sur @franceculture.fr ! #ScienceCQFD

An image with Uranus and several background stars labeled.

NASA’s Europa Clipper captured this image of a starfield - and the planet Uranus - on Nov. 5, 2025, while experimenting with one of its 2 stellar reference units. These star-tracking cameras are used for maintaining spacecraft orientation.

science.nasa.gov/photojournal... 🧪🔭 #Europa #EuropaClipper

Mars-bound ESCAPADE mission captures first selfies

One of the two #ESCAPADE spacecraft used its Visible and Infrared Observation System (VISIONS) cameras to capture images showing part of a solar panel, showing the cameras are working well. #Mars 🧪🔭

science.nasa.gov/blogs/escapa...

In Saturn's upper atmosphere G is 1.07 Earth G - it's a great place for flying cities (as is the atmosphere of Venus, btw).

You owe it to yourself to imagine a city in the upper atmosphere of Saturn today.

A shallow circular hole abraded into the rock surface by Perseverance rover - a debris pile of fresh rock dust is spread to one side.

NASA Mars Perseverance Rover at Jezero crater
Sol 1,693 (24th Nov, 2025)

Latest abrasion

MastCam-Z (left) ZCAM04280
Site 81 / 3608
📷 Credits: NASA / JPL-Caltech / ASU / MSSS / Martian-Observer

A small plateau located a spine of mountains separating Coprates Chasma (a main canyon in the Valles Marineris system) from a smaller side canyon paralleling it to the south. This plateau appears to be a small remnant of the flat upland surface present to the north and south of the Valles Marineris. At least two different layers of rock are visible along the sides of this plateau. Similar layers are found along the rim of Valles Marineris. It is unclear when these layers formed, but they were perhaps deposited during the opening stages of Coprates Chasma's formation, when the region started to subside but had yet to form the deep canyons of today.. This image was created using the CRISM imaging spectrometer. Each pixel of a CRISM image contains a 500 point spectrum, from which a color can be reconstructed. This reconstructed color was overlaid on a higher-resolution image taken with the Mars Reconnaissance Orbiter Context Camera (CTX), which simultaneously took a photo while CRISM was collecting data. This image was taken on January 2, 2007. It uses CRISM observation HRS00003B3C and CTX observation P03_002036_1655_XI_14S055W. Image Credit: NASA / JPL / JHUAPL / MSSS / Justin Cowart

Coprates Chasma - Mars Reconnaissance Orbiter - From Aster Cowart (terrasabaea.bsky.social) - https://flic.kr/p/2kfw6WT

Une représentation de fluctuations quantiques illustre l'annonce de la prochaine conférence publique de l'IAP : L'inflation cosmologique : l'Univers primordial comme laboratoire pour la physique fondamentale », par Sébastien Renaux-Petel, mardi 2 décembre à 19h30. Crédit : Derek Leinweber - Visualizations of Quantum Chromodynamics. En savoir plus sur Wikipedia : https://en.wikipedia.org/wiki/Quantum_fluctuation#/media/File:Quantum_Fluctuations.gif

📣Conférence publique @iap.fr par Sébastien Renaux-Petel, mardi 2 décembre 2025 à 19h30, en direct sur youtu.be/Ll_WByiBvu0 📡programme sur www.iap.fr/science/conf... @cnrs-insu.bsky.social @cnrs-paris.bsky.social @sorbonne-universite.fr

For many, nothing evokes fall more than fallen leaves. In this view of NGC 6334, glowing pockets of dust and gas in the nebula resemble leaves that have been picked up by a wind gust. This region is actually home to strong winds blowing from the young stars that have formed there. This image contains X-ray data from Chandra (blue, green, and yellow) that shows the effects of these winds, which have been combined with infrared data from the now-retired Spitzer Space Telescope (red, brown), which shows the dust and gas that fuels the growing stars. Credit: X-ray: NASA/SAO/CXC; Infrared: NASA/JPL/CalTech/Spitzer; Image Processing: NASA/CXC/SAO/J. Schmidt

Born after a violent explosion of a star, this cosmic gourd is the supernova remnant G272.2-03.2. X-ray observations (orange and magenta) from Chandra provide evidence that G272 is the result of a Type Ia supernova explosion, where a white dwarf star pulls material from a companion star until it triggers a thermonuclear explosion and obliterates the star. The inside of the “pumpkin” is superheated gas that is filling the space cleared out by the explosion as it moves outward. Credit: X-ray: NASA/CXC/SA0; Optical: NOIRLab/DECaPS2; Image Processing: NASA/CXC/SAO/L. Frattare

Multiple telescopes teamed up to capture an image that looks like a cozy sweater with fuzzy arms. X-rays from Chandra and ESA’s XMM-Newton (purple), optical light data from Hubble and the Very Large Telescope in Chile (orange, red, and violet), and an optical image from astrophotographer Bob Fera (deep blue) combine to reveal R Aquarii. Nestled within the cozy ‘body’ of R Aquarii is a pair of stars where a white dwarf is pulling material from a much larger red giant companion. When enough material accumulates on the surface of the white dwarf, it triggers an outburst that sends a jet out into space. Over time, these jets twist and loop around each other weaving the structure seen today. Credit: X-ray: NASA/CXC/SAO; ESA/XMM-Newton; Optical HST: NASA/ESA/STScI; Optical Ground: Deep Space Remote observatories/B. Fera; ESO/VLT; Image Processing: NASA/CXC/SAO/L. Frattare

A cornucopia is a horn-shaped basket that traditionally carries fruits and vegetables. There is nothing edible in this pair of galactic cornucopias but there are a bounty of stars, dust, and other ingredients than make up these two spiral galaxies, known as NGC 2207 (right) and IC 2163 (left), that we see face-on. This view of NGC 2207 and IC 2163 takes a James Webb infrared image (white, gray, and red) and adds the X-ray view from Chandra (blue). Together, it is quite an eye-catching result. Credit: X-ray: NASA/CXC/SAO; Infrared: NASA/ESA/CSA/STScI/Webb; Image Processing: NASA/CXC/SAO/L. Frattare

Chandra's Fall Collection 🍂

A quartet of images that invoke themes associated with autumn

1. NGC 6334 nebula: Cosmic leaves blowing
2. SNR G272.2-03.2: The Space Pumpkin
3. R Aquarii: A cosmic sweater
4. NGC 2207 and IC 2163: A pair of galactic cornucucopia

chandra.harvard.edu/photo/2025/f... 🔭🧪

A view of the Licancabur volcano at sunset, located in the Atacama Desert near the Chile–Bolivia border. The volcano’s peak is bathed in orange and pink light. A neighbouring mountain lies in the background. The foreground shows the arid desert landscape.

The night sky is not the only marvel of the Atacama Desert.

One example? The Licancabur volcano, one of the great gatekeepers of ALMA. 5920 m high, it‘s part of a chain of mountains that separate Chile and Bolivia 🌋

https://www.eso.org/public/images/licancabur-yuri/  🔭

I do love me some spacecraft selfies :)

Mars-bound ESCAPADE mission captures first selfies

One of the two #ESCAPADE spacecraft used its Visible and Infrared Observation System (VISIONS) cameras to capture images showing part of a solar panel, showing the cameras are working well. #Mars 🧪🔭

science.nasa.gov/blogs/escapa...

The first page of a detailed account of Messier's unsuccessful attempts at confirming the existence of several nebulae reported by Hevelius, La Caille, Cassini, and Flamsteed.

The second page of a detailed account of Messier's unsuccessful attempts at confirming the existence of several nebulae reported by Hevelius, La Caille, Cassini, and Flamsteed.

Cosmography archives

Nêbuleuses découvertes par différens Astronomes, que M. Messier a cherchées inutilement.

Connoissance des Temps, ou Connoissance des Mouvemens Célestes, Pour l'Année bissextile 1784, pp 268-269.

gallica.bnf.fr/ark:/12148/b... 🧪🔭

Thank you for your past service, Senator Kelly - and for your service today, by standing up to the authoritarians.

🔭

Fighting for ‘The Right to Night’ Under Starry, Rural Skies

have you ever been somewhere so dark you could step outside & immediately spot the Milky Way? i traveled to the Upper Peninsula to learn about efforts to balance industrialization & economic growth with the preservation of starry skies:

www.nytimes.com/2025/11/24/s...

The first page of a detailed account of Messier's unsuccessful attempts at confirming the existence of several nebulae reported by Hevelius, La Caille, Cassini, and Flamsteed.

The second page of a detailed account of Messier's unsuccessful attempts at confirming the existence of several nebulae reported by Hevelius, La Caille, Cassini, and Flamsteed.

Cosmography archives

Nêbuleuses découvertes par différens Astronomes, que M. Messier a cherchées inutilement.

Connoissance des Temps, ou Connoissance des Mouvemens Célestes, Pour l'Année bissextile 1784, pp 268-269.

gallica.bnf.fr/ark:/12148/b... 🧪🔭

Blog: 25 Years of Gemini Part I: The Origin of the International Gemini Observatory How a bold international collaboration launched an ambitious project to create the next generation of world-class 8-... 25 Years of Gemini Part I: The Origin of the International Gemini Observatory

From @noirlabastro.bsky.social: To celebrate 25 years of the Gemini Observatory, we’re launching a two-part Blog series! Today, we’re exploring the history of how an international collaboration created the next generation of world-class 8-meter telescopes. #astronomy

🔗 ow.ly/FNRC50XumLm

Tatiana Schlossberg, the granddaughter of JFK, says she has a rare terminal cancer In an essay in The New Yorker, Tatiana Schlossberg says she has acute myeloid leukemia. She also criticized her relative, Robert F. Kennedy Jr.

In an essay in The New Yorker, Tatiana Schlossberg says she has acute myeloid leukemia. She also criticized her relative, Robert F. Kennedy Jr. n.pr/4oWPvg3

Sympathetic cooling gives antihydrogen experiment a boost – Physics World Having more antimatter could help solve profound mysteries of physics

Physicists working on the ALPHA experiment at CERN have trapped and accumulated 15,000 antihydrogen atoms in less than 7 h. This accumulation rate is more than 20 times the previous record. 🧪⚛️ ow.ly/iKgP50XvMEC

Maybe That’s Not Liquid Water on Mars After All - Eos A “very large roll” of a radar instrument offers new insight into a highly reflective area near the Martian south pole.

A highly reflective area at the base of Mars's southern polar ice cap hinted at the potential presence of liquid water. But new radar measurements suggest there may be another explanation. New research in #AGUPubs by scientists at @psi.edu & colleagues.

An image with Uranus and several background stars labeled.

NASA’s Europa Clipper captured this image of a starfield - and the planet Uranus - on Nov. 5, 2025, while experimenting with one of its 2 stellar reference units. These star-tracking cameras are used for maintaining spacecraft orientation.

science.nasa.gov/photojournal... 🧪🔭 #Europa #EuropaClipper

A cover of the Métal Hurlant magazine. The pink toned art by Jacques Tardi features a yellow-eyed, crazy looking giant robot biting into Tintin's white-and-red lunar rocket. Mentions specify that that this monthly publication if for adults, and that the included comic strips are humor and science fiction themed.

Tardi's robot eating Hergé's rocket: an iconoclast cover for the issue N°9 of Métal Hurlant, published in September 1976

@metalhurlantoff.bsky.social ⚡

James Clerk Maxwell Telescope Helps Discover 13 Distant, Dusty Galaxies — Maunakea Observatories Utilizing the James Clerk Maxwell Telescope (JCMT) on Maunakea and the J ames Webb Space Telescope (JWST), researchers confirmed the existence of 13 new strongly lensed, distant dusty galax...

James Clerk Maxwell Telescope Helps Discover 13 Distant, Dusty Galaxies

www.maunakeaobservatories.org/stories/jame...

🔭🧪 #Maunakea

Jupiter hier matin depuis Paris