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27/08/2022

ASTRONOMY - IC 5146: The Cocoon Nebula

 2022 August 27

See Explanation.  Clicking on the picture will download
the highest resolution version available.

IC 5146: The Cocoon Nebula
Image Credit & CopyrightDavid Jenkins

Explanation: Inside the Cocoon Nebula is a newly developing cluster of stars. Cataloged as IC 5146, the beautiful nebula is nearly 15 light-years wide. Climbing high in northern summer night skies, it's located some 4,000 light years away toward the constellation Cygnus the Swan. Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by young, hot stars, and dust-reflected starlight at the edge of an otherwise invisible molecular cloud. In fact, the bright star found near the center of this nebula is likely only a few hundred thousand years old, powering the nebular glow as it clears out a cavity in the molecular cloud's star forming dust and gas. A 29 hour long integration with a small telescope from Ayr, Ontario, Canada resulted in this exceptionally deep color view tracing tantalizing features within and surrounding the dusty stellar nursery.

26/08/2022

MERVEILLEUX MONDE SOUS-MARIN - La gorgone rouge et le gorgonocéphale

 

Méditerranée - France - Archipel des Iles d'Hyères - Ile du Levant.

Gorgone rouge (Paramuricea clavata - Purple gorgonian) et gorgonocéphale (Astropartus mediterraneus - Basket star). Ces deux espèces vivent fréquemment associées l'une à l'autre.

© Alexis Rosenfeld
FuturaSciences

ASTRONOMY - Little Planet South Pole

 2022 August 26

See Explanation.  Clicking on the picture will download
the highest resolution version available.

Little Planet South Pole
Image Credit & CopyrightAman Chokshi

Explanation: Lights play around the horizon of this snowy little planet as it drifts through a starry night sky. Of course the little planet is actually planet Earth. Recorded on August 21, the digitally warped, nadir centered panorama covers nearly 360x180 degrees outside the Amundsen-Scott South Pole Station, Antarctica. The southernmost research outpost is near the horizon at the top where the light of dawn is approaching after nearly six months of darkness. Along the bottom is the ceremonial pole marker surrounded by the 12 flags of the original signatories of the Antarctic treaty, with a wild display of the aurora australis above.

25/08/2022

ASTRONOMY - Tiangong Space Station Transits the Moon

 2022 August 25

See Explanation.  Clicking on the picture will download
the highest resolution version available.

Tiangong Space Station Transits the Moon
Image Credit & CopyrightLucy Yunxi Hu

Explanation: The rugged lunar south polar region lies at the top of this colorful portrait of a last quarter Moon made on August 20. Constructed from video frames and still images taken at Springrange, New South Wales, Australia it also captures a transit of China's Tiangong Space Station. The transit itself was fleeting, taking the space station less than a second to cross the shadowed and sunlit lunar disk. The low Earth orbiting Tiangong is at an altitude of about 400 kilometers, while the Moon is some 400,000 kilometers away. Subtle color differences along the bright lunar surface are revealed in the multiple stacked frames. Not visible to the eye, they indicate real differences in chemical makeup across the lunar surface.

24/08/2022

ASTRONOMY - The Cartwheel Galaxy from Webb

 2022 August 24

The featured image shows the interacting Cartwheel
Galaxy as captured in visible and infrared light by the
Webb Space Telescope.
Please see the explanation for more detailed information.

The Cartwheel Galaxy from Webb
Image Credit: NASAESACSASTScI, Webb ERO Production Team

Explanation: To some, it looks like a wheel of a cart. In fact, because of its outward appearance, the presence of a central galaxy, and its connection with what looks like the spokes of a wheel, the galaxy on the right is known as the Cartwheel Galaxy. To others, however, it looks like a complicated interaction between galaxies awaiting explanation. Along with the two galaxies on the left, the Cartwheel is part of a group of galaxies about 500 million light years away in the constellation Sculptor. The large galaxy's rim spans over 100,000 light years and is composed of star forming regions filled with extremely bright and massive stars. The Cartwheel's ring-like shape is the result of gravitational disruption caused by a smaller galaxy passing through a large one, compressing the interstellar gas and dust and causing a star formation wave to move out like a ripple across the surface of a pond. The featured recent image of the Cartwheel Galaxy by the Webb Space Telescope reveals new details not only about where stars are forming, but also about activity near the galaxy's central black hole.

23/08/2022

ASTRONOMY - Meteor & Milky Way over the Mediterranean

 2022 August 23

The featured image shows a beach nighscape featuring a bright meteor,
the band of our Milky Way Galaxy, and a small island in the 
Mediterranean Sea of France.
Please see the explanation for more detailed information.

Meteor & Milky Way over the Mediterranean
Image Credit & Copyright: Julien Looten

Explanation: Careful planning made this a nightscape to remember. First, the night itself was chosen to occur during the beginning of this year's Perseid Meteor Shower. Next, the time of night was chosen to be before the bright Moon would rise and dominate the night sky's brightness. The picturesque foreground was selected to be a rocky beach of the Mediterranean Sea in Le Dramont, France, with, at the time, île d’Or island situated near the ominously descending central band of our Milky Way Galaxy. Once everything was set and with the weather cooperating, all of the frames for this seemingly surreal nightscape were acquired within 15 minutes. What you can't see is that, on this night, the astrophotographer brought along his father who, although unskilled in modern sky-capture techniques, once made it a point to teach his child about the sky.

22/08/2022

MERVEILLEUX MONDE SOUS-MARIN - Poissons-clowns de Clark dans leur anémone


Atoll de Fakarava, passe de Tetamanu. Réserve de la biosphère.

Poissons-clowns de Clark (Amphipirion clarkii) au-dessus de l'anémone magnifique (Heteractis magnifica) dans laquelle ils habitent. Immunisés contre ses toxines, ils profitent de l'abri offert par l'anémone contre les prédateurs, qui eux craignent son poison.

© Photographe Alexis Rosenfeld
FuturaSciences

ASTRONOMY - Earth's Recent Climate Spiral

 2022 August 22

Earth's Recent Climate Spiral
Video Credit: NASA's Scientific Visualization Studio

Explanation: Is our Earth warming? Compared to the past 250 million years, the Earth is currently enduring a relative cold spell, possibly about four degrees Celsius below average. Over the past 120 years, though, data indicate that the average global temperature of the Earth has increased by nearly one degree Celsius. The featured visualization video depicts Earth's recent global warming in graphic terms. The depicted temperatures are taken from the Goddard Institute for Space StudiesSurface Temperature Analysis. Already noticeable by many, Earth's recent warming trend is causing sea levels to riseprecipitation patterns to change, and pole ice to melt. Few now disagree that recent global warming is occurring, and the Intergovernmental Panel on Climate Change (IPCC) has concluded that we humans have created a warming surge that is likely to continue. A continuation could impact many local agricultures and even the global economy. Although there seems to be no simple solutionsgeoengineering projects that might help include artificial cloud creation to reduce the amount of sunlight heating the Earth's surface.

21/08/2022

ASTRONOMY - The Spinning Pulsar of the Crab Nebula

 2022 August 21

The featured image shows the center of the Crab Nebula
in colors mapped to Hubble, Chandra, and Spitzer space 
telescopes. The Crab pulsar appears in the center surrounded
by a spinning disk.
Please see the explanation for more detailed information.

The Spinning Pulsar of the Crab Nebula
Image Credit: NASA: X-ray: Chandra (CXC), Optical: Hubble (STScI), Infrared: Spitzer (JPL-Caltech)

Explanation: At the core of the Crab Nebula lies a city-sized, magnetized neutron star spinning 30 times a second. Known as the Crab Pulsar, it is the bright spot in the center of the gaseous swirl at the nebula's core. About twelve light-years across, the spectacular picture frames the glowing gas, cavities and swirling filaments near the Crab Nebula's center. The featured picture combines visible light from the Hubble Space Telescope in purple, X-ray light from the Chandra X-ray Observatory in blue, and infrared light from the Spitzer Space Telescope in red. Like a cosmic dynamo the Crab pulsar powers the emission from the nebula, driving a shock wave through surrounding material and accelerating the spiraling electrons. With more mass than the Sun and the density of an atomic nucleus,the spinning pulsar is the collapsed core of a massive star that exploded. The outer parts of the Crab Nebula are the expanding remnants of the star's component gasses. The supernova explosion was witnessed on planet Earth in the year 1054.

20/08/2022

MACROPHOTOGRAPHIE - Le pissenlit jamais imaginé

 
Chez le pissenlit, l'ovaire de chaque fleur donne un akène, un fruit sec qui contient une graine.
Chaque akène est surmonté d'un pappus en forme de parachute. Un coup de vent -- ou le passage d'un animal -- et les akènes mûrs se détachent pour être disséminés, parfois sur de longues distances.

Une stratégie poétique mise en œuvre par la nature et magnifiée ici par la photographe japonaise Miki Asai. Une légère brume créée avec les moyens du bord -- un spray usagé pour cheveu -- et une belle goutte d'eau bien ronde délicatement déposée au centre à l'aide d'un compte-goutte. Laissez ensuite simplement agir la magie du reflet arrondi de cette fleur dans l'eau. 

© Miki Asai

ASTRONOMIE - Galaxies - NGC 4603

La distance de cette galaxie a été mesurée précisément grâce aux Céphéides qu'on y observe. Elle est située à 108 millions d' anné...