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27/02/2026
Microphotographie - LES ANTENNES : ORGANE VITALPOUR LES ABEILLES
26/02/2026
Astronomy - WEBB AND HUBBLE - IC 5332
2026 February 26
Image Credit: ESA/Webb, NASA, CSA, J. Lee and the PHANGS-JWST and PHANGS-HST Teams
Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)
Explanation: What does the universe look like through infrared goggles? Our eyes can only see visible light, but astronomers want to see more. Today’s APOD shows spiral galaxy IC 5332 as seen by two NASA telescopes: Webb in mid-infrared and Hubble in ultraviolet and visible light. To toggle between the two space-based views just slide your cursor over the image (or follow this link). The Hubble image highlights the spiral arms of the galaxy separated by dark regions, whereas the Webb image reveals a finer, more tangled structure. Interstellar dust scatters and absorbs light from the stars in the galaxy, causing the dark dust lanes in the Hubble image, and then emits heat in infrared light, so dust glows in this Webb image. The Mid-InfraRed Instrument on Webb needs to operate at a chilling temperature of -266ºC (or - 447ºF), otherwise it would detect infrared radiation from the telescope itself. Combining these observations, astronomers connect the “small scale” of gas and stars to the truly large scale of galactic structure and evolution.
25/02/2026
Astronomy - THE EGG NEBULA FROM THE HUBBLE TELESCOPE
2026 February 25
Image Credit & Copyright: ESA/Hubble & NASA, B. Balick (U. Washington)
Explanation: Ever wonder what it would look like to crack open the Sun? The Egg Nebula, a dying Sun-like star, can unscramble this question. Pictured is a combination of several visible and infrared images of the nebula (also known as RAFGL 2688 or CRL 2688) taken with the Hubble Space Telescope. The star has shed its outer layers, and a bright, hot core (or "yolk") now illuminates the milky "egg white" shells of gas and dust surrounding the center. The central lobes and rings are structures of gas and dust recently ejected into space, with the dust being dense enough to block our view of the stellar core. Light beams emanate from that blocked core, escaping through holes carved in the older ejected material by newer, faster jets expelled from the star’s poles. Astronomers are still trying to figure out what causes the disks, lobes, and jets during this short (only a few thousand years!) phase of the star’s evolution, making this an egg-cellent image to study!
23/02/2026
LINGUISTIQUE - Les origines de la langue basque - (2/2)
ASTRONOMY - Pleiades: The Seven Sisters Star Cluster
2026 February 23
Image Credit & Copyright: Kamil Fiedosiuk
Explanation: Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The featured 18-hour exposure, taken from Bory Tucholskie, Poland covers a sky area several times the size of the full moon. Also known as the Seven Sisters and M45, the Pleiades lies about 400 light years away toward the constellation of the Bull (Taurus). A common legend with a modern twist is that one of the brighter stars faded since the cluster was named, leaving only six of the sister stars visible to the unaided eye. The actual number of Pleiades stars visible, however, may be more or less than seven, depending on the darkness of the surrounding sky and the clarity of the observer's eyesight.
20/02/2026
ASTRONOMY - B93: A Dark Interstellar Ghost
Image Credit & Copyright: Christian Bertincourt; Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II)
Explanation: "A ghost in the Milky Way…” says Christian Bertincourt, the astrophotographer behind this striking image of Barnard 93 (B93). The 93rd entry in Barnard’s Catalogue of Dark Nebulae, B93 lies within the Small Sagittarius Star Cloud (Messier 24), where its darkness stands in stark contrast to bright stars and gas in the background. In some ways, B93 is really like a ghost, because it contains gas and dust that was dispersed by the deaths of stars, like supernovas. B93 appears as a dark void not because it is empty, but because its dust blocks the light emitted by more distant stars and glowing gas. Like other dark nebulas, some gas from B93, if dense and massive enough, will eventually gravitationally condense to form new stars. If so, then once these stars ignite, B93 will transform from a dark ghost into a brilliant cradle of newborn stars.
19/02/2026
ASTRONOMY - IC 2574: Coddington's Nebula
2026 February 19
Image Credit & Copyright: Dane Vetter
Explanation: Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact, dwarf galaxy IC 2574 shows clear evidence of intense star forming activity in its telltale reddish regions of glowing hydrogen gas. Just as in spiral galaxies, the turbulent star-forming regions in IC 2574 are churned by stellar winds and supernova explosions spewing material into the galaxy's interstellar medium and triggering further star formation. A mere 12 million light-years distant, IC 2574 is part of the M81 group of galaxies, seen toward the northern constellation Ursa Major. Also known as Coddington's Nebula, the faint but intriguing island universe is about 50,000 light-years across, discovered by American astronomer Edwin Coddington in 1898.
18/02/2026
ASTRONOMY - Orion's Cradle
2026 February 18
Image Credit & Copyright: Piotr Czerski
Explanation: Cradled in red-glowing hydrogen gas, stars are being born in Orion. These stellar nurseries lie at the edge of the giant Orion molecular cloud complex, some 1,500 light-years away. This detailed view spans about 12 degrees across the center of the well-known constellation, with the Great Orion Nebula, the closest large star-forming region, visible toward the lower right. The deep mosaic also includes, near the top center, the Flame Nebula and the Horsehead Nebula. Image data acquired with a hydrogen-alpha filter adds other remarkable features to this wide-angle cosmic vista: pervasive tendrils of energized atomic hydrogen gas and portions of the surrounding Barnard's Loop. While the Orion Nebula and many stars in Orion are easy to see with the unaided eye, emission from the extensive interstellar gas is faint and much harder to record, even in telescopic views of the nebula-rich complex.
17/02/2026
LINGUISTIQUE - Les origines de la langue basque - (1/2)
ASTRONOMY - Tails of Comet Wierzchoś
2026 February 17
Image Credit & Copyright: José J. Chambó;
Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)
Explanation: Some comets are regular guests of our solar neighborhood; others come by only once, never to return. We won’t have another chance to see Comet C/2024 E1 (Wierzchoś), which is currently making its way through the inner Solar System. The hyperbolic orbit of this comet indicates that it will likely become an interstellar traveler. Comet Wierzchoś is today near its closest approach to the Earth, passing roughly the same distance from the Earth as is the Sun. The featured 30-minute exposure was taken last week in Chile and shows a 5-degree long ion tail as well as three shorter dust tails. The green hue of the coma comes from the breakdown of dicarbon molecules by sunlight, but that process does not last long enough to also tinge the tails. On the far right lies a spiral galaxy far in the distance: NGC 300.
Astronomy - THE CRANIUM NEBULA FROM THE WEBB TELESCOPE
2026 March 9 The Cranium Nebula from the Webb Telescope Image Credit: NASA , ESA , CSA , STScI ; Processing: J. DePasquale ( STScI ) ...
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2025 May 11 The Surface of Venus from Venera 14 Image Credit: Soviet Planetary Exploration Program , Venera 14 ; Processing & Copyri...
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2025 April 14 The Galactic Center in Radio from MeerKAT Image Credit: NASA , ESA , CSA , STScI , SARAO , S. Crowe ( UVA ), J. Bally ...






