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24/05/2023
ART FRACTAL - La fractale de Superman
ARCHEOLOGIE - Une étonnante épave d'un navire romain découvert en Méditerranée
ASTRONOMY - Observatory Aligned with Moon Occulting Jupiter
2023 May 24
Image Credit & Copyright: Rick Whitacre; Text: Natalia Lewandowska (SUNY Oswego)
Explanation: Sometimes we witness the Moon moving directly in front of -- called occulting -- one of the planets in our Solar System. Earlier this month that planet was Jupiter. Captured here was the moment when Jupiter re-appeared from behind the surface of our Moon. The Moon was in its third quarter, two days before the dark New Moon. Now, our Moon is continuously half lit by the Sun, but when in its third quarter, relatively little of that half can be seen from the Earth. Pictured, the Moon itself was aligned behind the famous Lick Observatory in California, USA, on the summit of Mount Hamilton. Coincidentally, Lick enabled the discovery of a moon of Jupiter: Amalthea, the last visually detected moon of Jupiter after Galileo's observations.
23/05/2023
ASTRONOMY - Tardigrade in Moss
2023 May 21
Image Credit & Copyright: Nicole Ottawa & Oliver Meckes / Eye of Science / Science Source Images
Explanation: Is this an alien? Probably not, but of all the animals on Earth, the tardigrade might be the best candidate. That's because tardigrades are known to be able to go for decades without food or water, to survive temperatures from near absolute zero to well above the boiling point of water, to survive pressures from near zero to well above that on ocean floors, and to survive direct exposure to dangerous radiations. The far-ranging survivability of these extremophiles was tested in 2011 outside an orbiting space shuttle. Tardigrades are so durable partly because they can repair their own DNA and reduce their body water content to a few percent. Some of these miniature water-bears almost became extraterrestrials in 2011 when they were launched toward to the Martian moon Phobos, and again in 2021 when they were launched toward Earth's own moon, but the former launch failed, and the latter landing crashed. Tardigrades are more common than humans across most of the Earth. Pictured here in a color-enhanced electron micrograph, a millimeter-long tardigrade crawls on moss.
ASTRONOMY - Jupiter's Swirls from Juno
2023 May 23
Image Credit: NASA/JPL-Caltech/SwRI/MSSS; Processing & License: Kevin M. Gill
Explanation: Big storms are different on Jupiter. On Earth, huge hurricanes and colossal cyclones are centered on regions of low pressure, but on Jupiter, it is the high-pressure, anti-cyclone storms that are the largest. On Earth, large storms can last weeks, but on Jupiter they can last years. On Earth, large storms can be as large as a country, but on Jupiter, large storms can be as large as planet Earth. Both types of storms are known to exhibit lightning. The featured image of Jupiter's clouds was composed from images and data captured by the robotic Juno spacecraft as it swooped close to the massive planet in August 2020. A swirling white oval is visible nearby, while numerous smaller cloud swirls extend into the distance. On Jupiter, light-colored clouds are usually higher up than dark clouds. Despite their differences, studying storm clouds on distant Jupiter provides insights into storms and other weather patterns on
20/05/2023
ASTRONOMY - Galileo's Europa
2023 May 20
Image Credit: NASA, JPL-Caltech, SETI Institute, Cynthia Phillips, Marty Valenti
Explanation: Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon's icy surface likely hides a deep, global ocean. Galileo's Europa image data has been remastered here, with improved calibrations to produce a color image approximating what the human eye might see. Europa's long curving fractures hint at the subsurface liquid water. The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support life, making Europa one of the best places to look for life beyond Earth. What kind of life could thrive in a deep, dark, subsurface ocean? Consider planet Earth's own extreme shrimp.
17/05/2023
ASTRONOMY - Sunspot with Light Bridge
2023 May 17
Image Credit & Copyright: Mark Johnston
Explanation: Why would a small part of the Sun appear slightly dark? Visible is a close-up picture of sunspots, depressions on the Sun's surface that are slightly cooler and less bright than the rest of the Sun. The Sun's complex magnetic field creates these cool regions by inhibiting hot material from entering the spots. Sunspots can be larger than the Earth and typically last for about a week. Part of active region AR 3297 crossing the Sun in early May, the large lower sunspot is spanned by an impressive light bridge of hot and suspended solar gas. This high-resolution picture also shows clearly that the Sun's surface is a bubbling carpet of separate cells of hot gas. These cells are known as granules. A solar granule is about 1000 kilometers across and lasts for only about 15 minutes.
16/05/2023
ASTRONOMY - Total Eclipse: The Big Corona
2023 May 16
Image Credit & Copyright: Reinhold Wittich
Explanation: Most photographs don't adequately portray the magnificence of the Sun's corona. Seeing the corona first-hand during a total solar eclipse is unparalleled. The human eye can adapt to see coronal features and extent that average cameras usually cannot. Welcome, however, to the digital age. The featured image digitally combined short and long exposures taken in Exmouth, Australia that were processed to highlight faint and extended features in the corona during the total solar eclipse that occurred in April of 2023. Clearly visible are intricate layers and glowing caustics of an ever changing mixture of hot gas and magnetic fields in the Sun's corona. Looping prominences appear bright pink just past the Sun's edge. Images taken seconds before and after the total eclipse show glimpses of the background Sun known as Baily's Beads and diamond ring effect. The next total solar eclipse will cross North America in April of 2024.
15/05/2023
ASTRONOMY - M16: Eagle Nebula Deep Field
023 May 15
Image Credit & Copyright: Gianni Lacroce
Explanation: From afar, the whole thing looks like an eagle. A closer look at the Eagle Nebula, however, shows the bright region is actually a window into the center of a larger dark shell of dust. Through this window, a brightly-lit workshop appears where a whole open cluster of stars is being formed. In this cavity, tall pillars and round globules of dark dust and cold molecular gas remain where stars are still forming. Already visible are several young bright blue stars whose light and winds are burning away and pushing back the remaining filaments and walls of gas and dust. The Eagle emission nebula, tagged M16, lies about 6500 light years away, spans about 20 light-years, and is visible with binoculars toward the constellation of the Serpent (Serpens). This picture involved long and deep exposures and combined three specific emitted colors emitted by sulfur (colored as yellow), hydrogen (red), and oxygen (blue).
14/05/2023
ART FRACTAL - Fractale symétrique aux allures de flocon de neige
LA TERRE VUE DU CIEL - Le triangle Turin - Marseille - Lyon
Cette image a été acquise alors que la Station spatiale survolait la frontière entre la Belgique et la France. Elle montre le triangle form...
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2022 September 26 All the Water on Planet Earth Illustration Credit: Jack Cook, Adam Nieman, Woods Hole Oceanographic Institution ; Data ...
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2025 February 17 SpaceX Rocket Launch Plume over California Image Credit & Copyright: Martin LaMontagne Explanation: What's happe...