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11/11/2021

ASTRONOMY - NGC 1333: Stellar Nursery in Perseus

 2021 November 11

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

NGC 1333: Stellar Nursery in Perseus
Image Credit & Copyright: Michael Sherick

Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by interstellar dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This telescopic close-up spans about two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with telltale hints of contrasty red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains hundreds of stars less than a million years old, most still hidden from optical telescopes by the pervasive stardust. The chaotic environment may be similar to one in which our own Sun formed over 4.5 billion years ago.

09/11/2021

ASTRONOMY - A Waterfall and the Milky Way

 2021 November 1

The picture shows a waterfall under a night sky 
dominated by the arch of our Milky Way Galaxy. 
Please see the explanation for more detailed information.

A Waterfall and the Milky Way
Image Credit & Copyright: Xie Jie

Explanation: The dream was to capture both the waterfall and the Milky Way together. Difficulties included finding a good camera location, artificially illuminating the waterfall and the surrounding valley effectively, capturing the entire scene with numerous foreground and background shots, worrying that fireflies would be too distracting, keeping the camera dry, and avoiding stepping on a poisonous snake. Behold the result -- captured after midnight in mid-July and digitally stitched into a wide-angle panorama. The waterfall is the picturesque Zhulian waterfall in the Luoxiao Mountains in eastern Hunan ProvinceChina. The central band of our Milky Way Galaxy crosses the sky and shows numerous dark dust filaments and colorful nebulas. Bright stars dot the sky -- all residing in the nearby Milky Way -- including the Summer Triangle with bright Vega visible above the Milky Way's arch. After capturing all 78 component exposures for you to enjoy, the photographer and friends enjoyed the view themselves for the rest of the night.

08/11/2021

ASTRONOMY - A Filament Leaps from the Sun

 2021 November 8

A Filament Leaps from the Sun
Video Credit & Copyright: Stéphane Poirier

Explanation: Why, sometimes, does part of the Sun's atmosphere leap into space? The reason lies in changing magnetic fields that thread through the Sun's surface. Regions of strong surface magnetism, known as active regions, are usually marked by dark sunspots. Active regions can channel charged gas along arching or sweeping magnetic fields -- gas that sometimes falls backsometimes escapes, and sometimes not only escapes but impacts our Earth. The featured one-hour time-lapse video -- taken with a small telescope in France -- captured an eruptive filament that appeared to leap off the Sun late last month. The filament is huge: for comparison, the size of the Earth is shown on the upper left. Just after the filament lifted off, the Sun emitted a powerful X-class flare while the surface rumbled with a tremendous solar tsunami. A result was a cloud of charged particles that rushed into our Solar System but mostly missed our Earth -- this time. However, enough solar plasma did impact our Earth's magnetosphere to create a few faint auroras.

07/11/2021

ASTRONOMY - A Rorschach Aurora

 2021 October 30

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

A Rorschach Aurora
Image Credit & Copyright: Göran Strand

Explanation: If you see this as a monster's face, don't panic. It's only pareidolia, often experienced as the tendency to see faces in patterns of light and shadow. In fact, the startling visual scene is actually a 180 degree panorama of Northern Lights, digitally mirrored like inkblots on a folded piece of paper. Frames used to construct it were captured on a September night from the middle of a waterfall-crossing suspension bridge in Jamtland, Sweden. With geomagnetic storms triggered by recent solar activity, auroral displays could be very active at planet Earth's high latitudes in the coming days. But if you see a monster's face in your own neighborhood tomorrow night, it might just be Halloween.

06/11/2021

ASTRONOMY - Road to the Galactic Center

 2021 October 25

The picture shows the a composite image of Monument Valley, Utah, USA 
in the foreground, and the plane of the Milky Way Galaxy including 
the Galactic Center in the background. 
Please see the explanation for more detailed information.

Road to the Galactic Center
Image Credit & Copyright: Michael Abramyan

Explanation: Does the road to our galaxy's center go through Monument Valley? It doesn't have to, but if your road does -- take a picture. In this case, the road is US Route 163 and iconic buttes on the Navajo National Reservation populate the horizon. The band of Milky Way Galaxy stretches down from the sky and appears to be a continuation of the road on Earth. Filaments of dust darken the Milky Way, in contrast to billions of bright stars and several colorful glowing gas clouds including the Lagoon and Trifid nebulas. The featured picture is a composite of images taken with the same camera and from the same location -- Forest Gump Point in UtahUSA. The foreground was taken just after sunset in early September during the blue hour, while the background is a mosaic of four exposures captured a few hours later.

05/11/2021

ASTRONOMY - Lucy Launches to Eight Asteroids

 2021 October 20

The picture shows the NASA's Lucy mission
launching from Cape Canaveral, Florida. 
Please see the explanation for more detailed information.

Lucy Launches to Eight Asteroids
Image Credit & Copyright: John Kraus

Explanation: Why would this mission go out as far as Jupiter -- but then not visit Jupiter? Lucy's plan is to follow different leads about the origin of our Solar System than can be found at Jupiter -- where Juno now orbits. Jupiter is such a massive planet that its gravity captures numerous asteroids that orbit the Sun ahead of it -- and behind. These trojan asteroids formed all over our Solar System and some may have been trapped there for billions of years. Flying by these trojan asteroids enables studying them as fossils that likely hold unique clues about our early Solar System. Lucy, named after a famous fossil skeleton which was named after a famous song, is scheduled to visit eight asteroids from 2025 to 2033. Pictured, Lucy's launch was captured with reflection last week aboard a powerful Atlas V rocket from Cape CanaveralFloridaUSA.

04/11/2021

ASTRONOMY - Earthshine Moon over Sicily

2021 October 18
The picture shows the sky over Sicily, Italy earlier this month
featuring a crescent moon with Earthshine, Venus, and Antares.
Please see the explanation for more detailed information.

Earthshine Moon over Sicily
Image Credit & Copyright: Dario Giannobile

Explanation: Why can we see the entire face of this Moon? When the Moon is in a crescent phase, only part of it appears directly illuminated by the Sun. The answer is earthshine, also known as earthlight and the da Vinci glow. The reason is that the rest of the Earth-facing Moon is slightly illuminated by sunlight first reflected from the Earth. Since the Earth appears near full phase from the Moon -- when the Moon appears as a slight crescent from the Earth -- earthshine is then near its brightest. Featured here in combined, consecutively-taken, HDR images taken earlier this month, a rising earthshine Moon was captured passing slowly near the planet Venus, the brightest spot near the image center. Just above Venus is the star Dschubba (catalogued as Delta Scorpii), while the red star on the far left is Antares. The celestial show is visible through scenic cloud decks. In the foreground are the lights from Palazzolo Acreide, a city with ancient historical roots in SicilyItaly

MUSIC - Richard Wagner - The ride of Walkyries

"The ride of Walkyries"

03/11/2021

ASTRONOMY - Fireball over Lake Louise

 2021 October 12

The picture shows a bright meteor fireball 
over Lake Louise in Alberta, Canada. 
Please see the explanation for more detailed information.

Fireball over Lake Louise
Image Credit & Copyright: Hao Qin

Explanation: What makes a meteor a fireball? First of all, everyone agrees that a fireball is an exceptionally bright meteor. Past that, the International Astronomical Union defines a fireball as a meteor brighter than apparent magnitude -4, which corresponds (roughly) to being brighter than any planet -- as well as bright enough to cast a human-noticeable shadow. Pictured, an astrophotographer taking a long-duration sky image captured by accident the brightest meteor he had ever seen. Clearly a fireball, the disintegrating space-rock created a trail so bright it turned night into day for about two seconds earlier this month. The fireball has been artificially dimmed in the featured image to bring up foreground Lake Louise in AlbertaCanada. Although fireballs are rare, many people have been lucky enough to see them. If you see a fireball, you can report it. If more than one person recorded an image, the fireball might be traceable back to the Solar System body from which it was ejected.

02/11/2021

ASTRONOMY - Juno Flyby of Ganymede and Jupiter

Juno Flyby of Ganymede and Jupiter
Video Credit: Images: NASAJPL-CaltechSWRIMSSS;
Animation: Koji KuramuraGerald Eichstädt, Mike Stetson; Music: Vangelis

Explanation: What would it be like to fly over the largest moon in the Solar System? In June, the robotic Juno spacecraft flew past Jupiter's huge moon Ganymede and took images that have been digitally constructed into a detailed flyby. As the featured video begins, Juno swoops over the two-toned surface of the 2,000-km wide moon, revealing an icy alien landscape filled with grooves and craters. The grooves are likely caused by shifting surface plates, while the craters are caused by violent impacts. Continuing on in its orbit, Juno then performed its 34th close pass over Jupiter's clouds. The digitally-constructed video shows numerous swirling clouds in the north, colorful planet-circling zones and bands across the middle -- featuring several white-oval clouds from the String of Pearls, and finally more swirling clouds in the south. Next September, Juno is scheduled to make a close pass over another of Jupiter's large moons: Europa.

ASTRONOMIE - Collision entre deux planètes naines

Que se passe- t -il quand deux astres de la taille de Pluton entrent en collision ? Cette vue d'artiste reflète l'ampleur du phéno...