ASTRONOMY - Zeta and Rho Ophiuchi with Milky Way

 2025 May 27

Zeta and Rho Ophiuchi with Milky Way
Image Credit & Copyright: Ireneusz Nowak

Explanation: Behold one of the most photogenic regions of the night sky, captured impressively. Featured, the band of our Milky Way Galaxy runs diagonally along the bottom-left corner, while the colorful Rho Ophiuchi cloud complex is visible just right of center and the large red circular Zeta Ophiuchi Nebula appears near the top. In general, red emanates from nebulas glowing in the light of excited hydrogen gas, while blue marks interstellar dust preferentially reflecting the light of bright young stars. Thick dust usually appears dark brown. Many iconic objects of the night sky appear, including (can you find them?) the bright star Antares, the globular star cluster M4, and the Blue Horsehead nebula. This wide field composite, taken over 17 hours, was captured from South Africa last June.

ASTRONOMY - Spiral Galaxy NGC 2566 from Webb

 2025 May 26

Spiral Galaxy NGC 2566 from Webb
Image Credit: ESA/Webb, NASA & CSA, A. Leroy

Explanation: What’s happening in the center of spiral galaxy NGC 2566? First, the eight rays that appear to be coming out of the center in the featured infrared image are not real — they are diffraction spikes caused by the mechanical structure of the Webb space telescope itself. The center of NGC 2566 is bright but not considered unusual, which means that it likely contains a supermassive black hole, although currently not very active. At only 76 million light years away, the light we see from NGC 2566 today left when dinosaurs roamed the Earth. The picturesque galaxy is close enough so that Earthly telescopes, including Webb and Hubble, can resolve the turbulent clouds of gas and dust where stars can form and so allows study of stellar evolution. NGC 2566, similar in size to our Milky Way Galaxy, is notable for its bright central bar and its prominent outer spiral arms.

ASTRONOMY - Beneath Jupiter

 2025 May 25

Beneath Jupiter
Image Credit & Copyright: NASA, Juno, SwRI, MSSS; Processing & License: Gerald Eichstädt & Seán Doran

Explanation: Jupiter is stranger than we knew. NASA's Juno spacecraft has now completed over 70 swoops past Jupiter as it moves around its highly elliptical orbit. Pictured from 2017, Jupiter is seen from below where, surprisingly, the horizontal bands that cover most of the planet disappear into swirls and complex patterns. A line of white oval clouds is visible nearer to the equator. Impressive results from Juno show that Jupiter's weather phenomena can extend deep below its cloud tops, that Jupiter's center has a core that is unexpectedly large and soft, and that Jupiter's magnetic field varies greatly with location. Although Juno is scheduled to keep orbiting Jupiter further into 2025, at some time the robotic spacecraft will be maneuvered to plunge into the giant planet.

ASTRONOMY - Deimos Before Sunrise

2025 May 24

Deimos Before Sunrise
Image Credit: NASA, JPL-Caltech

Explanation: Deimos takes 30 hours and 18 minutes to complete one orbit around the Red Planet. That's a little more than one Martian day or sol which is about 24 hours and 40 minutes long, so Deimos drifts westward across the Martian sky. About 15 kilometers across at its widest, the smallest of Mars' two moons is bright though. In fact Deimos is the brightest celestial object in this Martian skyscape captured before sunrise by Perseverance on March 1, the 1,433rd sol of the Mars rover's mission. The image is a composed of 16 exposures recorded by one of the rover's navigation cameras. The individual exposures were combined into a single image for an enhanced low light view. Regulus and Algeiba, bright stars in the constellation Leo, are also visible in the dark Martian predawn sky.

SANTé/MEDECINE - Fruits chargés de pesticides - 1/2

Si manger des fruits est bon pour la santé, la présence de pesticides fait pencher la balance du mauvais côté.

Selon différentes enquêtes, trois quarts des fruits issus de l'agriculture non biologique présentent d'importantes quantités de pesticides.

Les raisins, les cerises, les clémentines et les fraises figurent parmi les fruits qui en contiennent le plus.

Les autorités de santé recommandent de consommer au moins cinq portions de fruits et légumes par jour. Avec l'été qui arrive, l'envie de manger des fruits se fait naturellement ressentir, d'autant plus que la saison nous donne une flopée de fruits riches en eau, en vitamines et peu caloriques. Si les fruits sont bons pour la santé, certains contiennent beaucoup plus de pesticides que d'autres, ce qui les rend donc nocifs pour nous.

Raisins, cerises, pamplemousse…

D'après l'ONG Générations Futures qui s'intéresse aux aliments végétaux non bio vendus en France, "56% des fruits testés contiennent au moins un résidu de pesticide Cancérigène ou Mutagène ou Reprotoxique détecté". Et parmi les fruits les plus "contaminés", figurent certaines stars de l'été, à savoir les raisins, les cerises, les fraises, les pamplemousses, les nectarines ou encore les pêches et les citrons verts. En effet, dans ces végétaux, "au moins un résidu de pesticide classé CMR est détecté le plus fréquemment". Ce n'est pas tout, les raisins et les cerises, mais aussi les clémentines, sont aussi les fruits qui présentent "les plus fortes fréquences d’échantillons dans lesquels a été détecté au moins un résidu de pesticide jugé perturbateur endocrinien". L'ONG rapporte également que "les cerises, les fraises et les raisins (50%) s’illustrent avec au moins la moitié de l’échantillonnage contenant au moins un résidu de pesticide PFAS". A contrario, parmi les fruits les moins contaminés, on retrouve les figues, le kiwi ou encore la banane.

Sabine BOUCHOUL pour TF1 INFO

ASTRONOMY - NGC 6366 vs 47 Ophiuchi

 2025 May 23

NGC 6366 vs 47 Ophiuchi
Image Credit & Copyright: Massimo Di Fusco

Explanation: Most globular star clusters roam the halo of our Milky Way galaxy, but globular cluster NGC 6366 lies close to the galactic plane. About 12,000 light-years away toward the constellation Ophiuchus, the cluster's starlight is dimmed and reddened by the Milky Way's interstellar dust when viewed from planet Earth. As a result, the stars of NGC 6366 look almost golden in this telescopic scene, especially when seen next to relatively bright, bluish, and nearby star 47 Ophiuchi. Compared to the hundred thousand stars or so gravitationally bound in distant NGC 6366, 47 Oph itself is a binary star system a mere 100 light-years away. Still, the co-orbiting stars of 47 Oph are too close together to be individually distinguished in the image.

LA TERRE VUE DU CIEL - La structure de Richat : l'œil de l'Afrique dans le désert de Mauritanie

La structure de Richat ou Richat Structure, dans le désert de Mauritanie est aussi surnommé l'œil de l'Afrique.

@ Nasa

ASTRONOMY - Curly Spiral Galaxy M63

 2025 May 22

Curly Spiral Galaxy M63
Image Credit & Copyright: Alberto Pisabarro

Explanation: A bright spiral galaxy of the northern sky, Messier 63 is nearby, about 30 million light-years distant toward the loyal constellation Canes Venatici. Also cataloged as NGC 5055, the majestic island universe is nearly 100,000 light-years across, about the size of our own Milky Way. Its bright core and majestic spiral arms lend the galaxy its popular name, The Sunflower Galaxy. This exceptionally deep exposure also follows faint loops and curling star streams far into the galaxy's halo. Extending nearly 180,000 light-years from the galactic center, the star streams are likely remnants of tidally disrupted satellites of M63. Other satellite galaxies of M63 can be spotted in the remarkable wide-field image, including dwarf galaxies, which could contribute to M63's star streams in the next few billion years.

LA TERRE VUE DU CIEL - Lever de Lune au-dessus du Pacifique par la sonde Rosetta

Cette photographie a été prise par la sonde Rosetta lors de son premier survol de la Terre le 4 mars 2005.

© Esa

ASTRONOMY - International Space Station Crosses the Sun

 2025 May 21

International Space Station Crosses the Sun
Image Credit & Copyright: Pau Montplet Sanz

Explanation: Typically, the International Space Station is visible only at night. Slowly drifting across the night sky as it orbits the Earth, the International Space Station (ISS) can be seen as a bright spot about once a month from many locations. The ISS is then visible only just after sunset or just before sunrise because it shines by reflected sunlight -- once the ISS enters the Earth's shadow, it will drop out of sight. The only occasion when the ISS is visible during the day is when it passes right in front of the Sun. Then, it passes so quickly that only cameras taking short exposures can visually freeze the ISS's silhouette onto the background Sun. The featured picture did exactly that -- it is actually a series of images taken a month ago from Sant Feliu de Buixalleu, Spain with perfect timing. This image series was later combined with a separate image highlighting the texture of the active Sun which included several Sun's prominences around the edge.