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22/08/2026

Astronomy - MOSTLY PERSEIDS

 2026 August 22

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

Mostly Perseids
Image Credit & Copyright: Jakub Koukal (Valašské Meziříčí Observatory)

Explanation: Recorded the night of August 12-13, images from four dedicated meteor-monitoring cameras at an astronomical observatory in Czechia were aligned and combined to create this all-night, all-sky view. On that night, the total count came to 1,706 meteors. And since that coincided with the peak activity of the 2026 Perseid Meteor Shower, most are perseids. Their overwhelming numbers make them easy to spot. Quite convincingly, perseid trails all trace back to a single radiant on the sky at the upper right, a region in the annual shower's eponymous constellation Perseus. But meteors belonging to other much less active showers can also revealed by finding their radiants too. For example, seen crossing the perseid trails are meteors from a shower whose radiant lies in Cygnus, known as Kappa Cygnids. The antihelion complex, a general region near Aquarius and opposite the Sun in the sky, is also identifiable as a weak source for meteors.

21/08/2026

Astronomy - SIMULATION TNG50 : A GALAXY CLUSTER FORMS


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.

Villes bioniques du futur - L'ARCHE BIONIQUE DE TAIWAN : UNE TOUR AUTOSUFFISANTE


Outre des panneaux solaires, trois éoliennes à axes verticaux fournissent l'énergie électrique. Les vitres, par effet de serre, assurent un apport thermique aux espaces intérieurs.

© Vincent Callebaut

20/08/2026

Astronomy - THE ELEPHANT'S TRUNK IN CEPHEUS

 2026 August 20

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

The Elephant's Trunk in Cepheus
Image Credit & Copyright: Eddie Sgarbossa

Explanation: Like an illustration in a galactic Just So Story, the Elephant's Trunk Nebula winds through the emission region and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. Also known as vdB 142, this cosmic elephant's trunk is over 20 light-years long. The detailed telescopic view features the bright swept-back ridges and pockets of cool interstellar dust and gas that abound in the region. But the dark, tendril-shaped clouds contain the raw material for star formation and hide protostars within. Nearly 3,000 light-years distant, the relatively faint IC 1396 complex covers a large region on the sky, spanning over 5 degrees. Top to bottom this proboscidean-like rendition reaches across an almost 1 degree wide field of view, though. That's a little less than the angular size of 2 full moons.

19/08/2026

Astronomy - RED SUN THROUGH WILDFIRE SMOKE

 2026 July 30

A deep red sun shows several sunspots.
	  Clouds and haze are visible.

Red Sun through Wildfire Smoke
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.

18/08/2026

Astronomy - PERSEIDS FROM PERSUS

 2026 August 18

A starfield is bounded by trees on three sides and
a pond on the bottom. Amongst the stars are many streaks
of light appearing to emanate from a place on the sky
just above a foreground bridge. 
Please see the explanation for more detailed information.

Perseids from Perseus
Image Credit & Copyright: Jakub Kuřák

Explanation: This was a good year for the Perseids meteor shower. A key reason was the Moon was absent from lighting up Earth's night sky so that more meteors were visible than usual. Where was the Moon? It was busy visiting the Sun. Near the Perseids peak, the Moon moved directly in front of the Sun and created a total solar eclipse visible from Greenland and Spain. The Perseids occur when the Earth collides with a stream of Sun-orbiting debris cast off by Comet Swift-Tuttle. Perseid meteors, although typically only the size of a sand grain, tend to be fast and bright because Swift-Tuttle's debris orbits the Sun in a direction partly opposite Earth's orbital motion. In the featured image compilation, accumulated over several nights from Jizerka in the Czech Republic, the Perseids meteor streaks can be traced back to a single location on the sky -- its radiant in Perseus.

17/08/2026

Monde sous-marin - ESCARGOT DES SOURCES HYDROTHERMALES DU JAPON


Ce mollusque gastéropode des sources hydrothermales, est un escargot du genre Alviniconcha associé à des symbiotes chimiotrophes. Cet individu, retrouvé au niveau du mont sous-marin de Suiyo (Japon), est le seul de son espèce jamais découvert.

© Yoshihiro FUJIWARA / JAMSTEC

Astronomy - A GOLDEN CORONA ECLIPSE

 2026 August 17

A total eclipse Sun is featured in the image center.
Around the Sun is a filamentary gold-hued corona flowing
out in all directions. 
Please see the explanation for more detailed information.

A Golden Corona Eclipse
Image Credit & Copyright: Rui Santos (Living Impressions)

Explanation: This total solar eclipse appeared not only poetically beautiful but scientifically interesting. Usually the solar corona appears white, and to some observers the corona of last week's total solar eclipse did appear this pearly color. But this time, totality observers in Spain saw a corona that appeared unusually golden. For one reason, from Spain, the totality occurred when the setting Sun was near the horizon. That low, sunlight travels through a large amount of air which scatters out blue light. An unusual amount of smoke in the air from nearby forest fires acted as a second filter, further scattering the remaining blue tones and deepening the already gold-dominated light. The HDR-processed, multiple-exposure featured image was captured from Benavente, Spain last week. One thing that did not appear golden was a hydrogen-glowing prominence that hovered over the Sun's left edge -- its original bright pink color survived.

16/08/2026

Villes bioniques du futur - L'ARCHE BIONIQUE DE TAIWAN : LA NATURE A LA VERTICALE


Dans le parc Gateway de Taichung, à Taiwan, cette tour est comme une forêt dans la ville. Des prairies et des jardins s'étalent en palier sur 390 m de hauteur dans un bâtiment autosuffisant, grâce aux énergies solaire et éolienne. On s'y promène pour apprécier la nature et pour trouver une vision panoramique sur la mégalopole. La tour sert aussi pour les relais de télécommunications.

© Vincent Callebaut

Astronomy - MILKY WAY OVER YELLOWSTONE

2026 August 16
A landscape image shows a starfield above a lake.
Part of the lake is evaporating into the sky on the 
right. The arch of the Milky Way Galaxy curves overhead.
It may look like the evaporation is creating the Milky Way.
Please see the explanation for more detailed information.

Milky Way over Yellowstone
Image Credit & Copyright: Dave Lane

Explanation: The Milky Way was not created by an evaporating lake. The colorful pool of water, about 10 meters across, is known as Silex Spring and is located in Yellowstone National Park in Wyoming, USA. Illuminated artificially, the colors are caused by layers of bacteria that grow in the hot spring. Steam rises off the spring, heated by underground magma associated with the Yellowstone Hotspot. Unrelated and far in the distance, the central band of our Milky Way Galaxy arches high overhead, a band lit by billions of stars. The picture features a 16-image panorama taken in 2014. If the Yellowstone Hotspot causes another supervolcanic eruption as it did about 640,000 years ago, a large part of North America 

Astronomy - MOSTLY PERSEIDS

 2026 August 22 Mostly Perseids Image Credit & Copyright : Jakub Koukal ( Valašské Meziříčí Observatory ) Explanation: Recorded the nig...