9 - SCIENCE - JoanMira
La Science sous toutes ses formes/Science in all its forms
Nombre total de pages vues
31/07/2026
Astronomy - NGC 4372 AND THE DARK DOODAD
Image Credit & Copyright: Alessandro Cipolat Bares
Explanation: The Dark Doodad Nebula drifts through southern skies, a tantalizing target for binoculars toward the small constellation Musca, The Fly. A dusty interstellar cloud, it's seen against rich starfields just south of the Coalsack Nebula and the Southern Cross. Stretching for about 3 degrees across this telescopic field of view, the Dark Doodad is punctuated near its southern tip (upper right) by yellowish globular star cluster NGC 4372. Of course NGC 4372 roams the halo of our Milky Way galaxy, a background object some 20,000 light-years away and only by chance along our line-of-sight to the Dark Doodad. About 700 light-years distant and over 30 light-years long, the Dark Doodad's well defined silhouette belongs to the potentially star-forming Musca molecular cloud. The dusty Dark Doodad's delightfully alliterative moniker was first coined by astro-imager and writer Dennis di Cicco in 1986 while observing Comet Halley from the Australian outback.
Santé/Médecine - LUTTE CONTRE LE CANCER - UN SERIEUX ESPOIR (5/6)
30/07/2026
Astronomy - RED SUN THROUGH WILDFIRE SMOKE
2026 July 30
Image Credit & Copyright: Debra Ceravolo
Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)
Explanation: This could be the view from an exoplanet orbiting around a red dwarf star, but it is our own Sun. This image was taken on July 22, 2026, in the Okanagan region in the Canadian province of British Columbia. Wildfire smoke from the Pacific Northwest acted as a solar filter, allowing the photographer to take this photo of the Sun directly. Several sunspots are also visible in this eerie image; just below and right of the center is AR 4493, a fast evolving, giant active solar region and sunspot group. The smoke is made of tiny particles that help block and scatter light with bluer colors, so the light we see coming from the Sun is dimmer and redder than usual (but it is never safe to stare directly at the Sun). Sunsets and sunrises are also more colorful because of the smoke. Some 6 billion years from now, the Sun will actually start to turn redder as it approaches its red giant phase.
29/07/2026
Santé/Médecine - LUTTE CONTRE LE CANCER - UN SERIEUX ESPOIR (4/6)
28/07/2026
Astronomy - BERNARD'S LOOP OVER TWIN VOLCANOES
2026 July 28
Image Credit & Copyright: Gonzalo Laserna Vargas
Explanation: What's connecting these two volcanoes? In ancient folklore, the two volcanoes, Parinacota (left) and Pomerape (right), are connected by representing a mythical prince and princess who engaged in a forbidden romance. Beneath the ground, the two peaks are not known to be connected by a common pool of hot magma, and neither volcano has erupted in the past 1000 years. Above the ground, there is usually nothing in the sky that connects them -- except if you use careful timing and look from a specific location. The featured well-planned image was captured from Bolivia in mid-April with a series of camera exposures taken on the same day and from the same location. Then, Barnard's Loop appeared to connect the volcanic peaks. Also visible in the image is the Orion Nebula in the center, the star Betelgeuse on the right, and the Rosette Nebula on the upper right.
26/07/2026
Astronomy - SIMULATION TNG50: A GALAXY CLUSTER FORMS
Video Credit: IllustrisTNG Project; Visualization: Dylan Nelson (Max Planck Institute for Astrophysics) et al.
Music: Symphony No. 5 (Ludwig van Beethoven), via YouTube Audio Library
Explanation: How do clusters of galaxies form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. One famous effort is TNG50 from IllustrisTNG, an upgrade of the famous Illustris Simulation. The first part of the featured video tracks cosmic gas (mostly hydrogen) as it evolves into galaxies and galaxy clusters from the early universe to today, with brighter colors marking faster moving gas. As the universe matures, gas falls into gravitational wells, galaxies forms, galaxies spin, galaxies collide and merge, all while black holes form in galaxy centers and expel surrounding gas at high speeds. The second half of the video switches to tracking stars, showing a galaxy cluster coming together, complete with stellar streams. The outflow from black holes in TNG50 is surprisingly complex and details are being compared with our real universe. Studying how gas coalesced in the early universe helps humanity better understand how our Earth, Sun, and Solar System originally formed.
Géoglyphes - LE SINGE DE NAZCA
25/07/2026
Santé/Médecine - LUTTE CONTRE LE CANCER : UN SERIEUX ESPOIR (3/6)
Véronique Molénat
FuturaSciences
24/07/2026
Astronomy - GIGANTIC JET OVER THE TATACOA DESERT
2026 July 15
Image Credit & Copyright: Mario Vargas
Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II)
Explanation: Is there an angry Sith using force lightning in the Tatacoa Desert? This is not science fiction, but a gigantic jet with multiple red streamers! Ordinary lightning occurs when thundercloud particles collide, lose their electrons, and build up negative charge at the cloud bottom. The cloud’s negative charge repels negative charge deeper into the Earth, leaving Earth’s surface positively charged. The opposite charges attract, reaching towards each other and superheating the air into a white strike of plasma. A gigantic jet occurs when internal cloud discharge escapes upward through a weak positive shielding layer, and shoots up from the cloud in less than a second. They extend up into the mesosphere where the air is too thin for thunder. The streamers at the top may resemble red sprites and get their color from heated molecular nitrogen.
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2026 January 2 NanoSail-D2 Image Credit & Copyright : Ralf Vandebergh Explanation: In 2011, on January 20, NASA's NanoSail-D2 ...
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2026 January 1 Auroral Corona Image Credit & Copyright : Roi Levi Explanation: Cycle 25 solar maximum made 2025 a great year for ...

