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The evidence for this mystery space rock comes from a diamond-studded meteor that exploded over Sudan in 2008. NASA had spotted the 9-ton (8,200 kilograms), 13-foot (4 meters) meteor heading toward the planet well before impact, and researchers showed up in the Sudanese desert to collect an unusually rich haul of remains. Now, a new study of one of those meteorites suggests that the meteor may have broken off of a giant asteroid — one more or less the size of the dwarf planet Ceres, the largest object in the asteroid belt. The meteorite harbored an unusual suite of minerals...

About 87 million miles (140 million kilometers) above the Grand Canyon, an even larger, grander abyss cuts through the gut of the Red Planet. Known as Valles Marineris, this system of deep, vast canyons runs more than 2,500 miles (4,000 km) along the Martian equator, spanning nearly a quarter of the planet's circumference. This gash in the bedrock of Mars is nearly 10 times as long as Earth's Grand Canyon and three times deeper, making it the single largest canyon in the solar system — and, according to ongoing research from the University of Arizona (UA) in Tucson, one of...

A group of galaxies nicknamed the Copeland Septet, in the constellation of Leo. Astronomers using images from Kitt Peak National Observatory and Cerro Tololo Inter-American Observatory have created the largest ever map of the sky, comprising over a billion galaxies. The final data release from the ambitious DESI Legacy Imaging Surveys sets the stage for a ground-breaking 5-year survey with the Dark Energy Spectroscopic Instrument (DESI), which aims to provide new insights into the nature of dark energy. Credit: KPNO/CTIO/NOIRLab/NSF/AURA/Legacy Imaging Survey ----------------------------------------------------------------------------------------------------- Giant Map of the Sky Sets Stage for Ambitious DESI Survey Astronomers using images from Kitt Peak...

Explanation: Why does a cloudy moon sometimes appear colorful? The effect, called a lunar corona, is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud. Since light of different colors has different wavelengths, each color diffracts differently. Lunar Coronae are one of the few quantum mechanical color effects that can be easily seen with the unaided eye. Solar coronae are also sometimes evident. The featured composite image was captured a few days before the close Great Conjunction between Saturn and Jupiter last month. In the foreground, the Italian village of...

Magazine article, no link. A reconstruction of our Milky Way's history finds that our galaxy has absorbed at least five large satellites. According to research of Diederik Kruijssen, Heidelberg University Germany. History of our most significant mergers with other galaxies is starting with "the Kraken", which collided with our galaxy around 11 billion years ago. The collision with Kraken must truly transformed our Milky Way Galaxy.

Explanation: What powers this unusual nebula? CTB-1 is the expanding gas shell that was left when a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. The star likely detonated when it ran out of elements, near its core, that could create stabilizing pressure with nuclear fusion. The resulting supernova remnant, nicknamed the Medulla Nebula for its brain-like shape, still glows in visible light by the heat generated by its collision with confining interstellar gas. Why the nebula also glows in X-ray light, though, remains a mystery. One hypothesis holds that an energetic pulsar was co-created that...

Artistic rendition of the exoplanet WASP-107b and its star, WASP-107. Some of the star's light streams through the exoplanet's extended gas layer. Credit: ESA/Hubble, NASA, M. Kornmesser. ======================================================== The core mass of the giant exoplanet WASP-107b is much lower than what was thought necessary to build up the immense gas envelope surrounding giant planets like Jupiter and Saturn, astronomers at Université de Montréal have found. This intriguing discovery by Ph.D. student Caroline Piaulet of UdeM's Institute for Research on Exoplanets (iREx) suggests that gas-giant planets form a lot more easily than previously believed. Piaulet is part of the groundbreaking research...

Researchers used the ALMA telescope array in Chile to discover the quasar A quasar is a type of supermassive black hole that is releasing a lot of energy This object was discovered when the universe was just 670 million years old The discovery can help researchers better understand how these objects form Its age and size brings into doubt theories they were formed from collapsed star clusters, with researchers suggesting they instead feast on cold hydrogen gas =========================================================== The most distant supermassive black hole known to science has been detected by astronomers - and it is more than 13 billion...

As the solar system was developing, the giant planets (Jupiter and Saturn) formed very early, and as they grew, they migrated both closer to and further away from the sun to stay in gravitationally stable orbits. The gravitational effect of these massive objects caused immense reshuffling of other planetary bodies that were forming at the time, meaning that the current locations of many planetary bodies in our solar system are not where they originally formed. Lawrence Livermore National Laboratory (LLNL) scientists set out to reconstruct these original formation locations by studying the isotopic compositions of different groups of meteorites that...

Seeing our world through the eyes of a migratory bird would be a rather spooky experience. Something about their visual system allows them to 'see' our planet's magnetic field, a clever trick of quantum physics, and biochemistry that helps them navigate vast distances. Now, for the first time ever, scientists from the University of Tokyo have directly observed a key reaction hypothesised to be behind birds', and many other creatures', talents for sensing the direction of the planet's poles. Importantly, this is evidence of quantum physics directly affecting a biochemical reaction in a cell – something we've long hypothesised but...

Explanation: Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax Cluster of galaxies. This impressively sharp color image shows the intense, reddish star forming regions near the ends of central bar and along the spiral arms, with details of the obscuring dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing...

From Jan. 9-12, Mercury, Jupiter, and Saturn will be visible in the southwestern sky. The celestial event is known as a “triple conjunction,” which means two planets and a third planet meet each other in the sky for a short period of time. Shortly after sunset on Jan. 9, look above the west-southwestern horizon and you will see Mercury to the left of Saturn and Jupiter positioned just above Saturn. “From Friday evening to Monday evening, the planet Mercury will appear to pass first by Saturn and then by Jupiter as it shifts away from the horizon, visible each evening...

Explanation: Why are these sand dunes on Mars striped? No one is sure. The featured image shows striped dunes in Kunowsky Crater on Mars, photographed recently with the Mars Reconnaissance Orbiter’s HiRISE Camera. Many Martian dunes are known to be covered unevenly with carbon dioxide (dry ice) frost, creating patterns of light and dark areas. Carbon dioxide doesn’t melt, but sublimates, turning directly into a gas. Carbon dioxide is also a greenhouse material even as a solid, so it can trap heat under the ice and sublimate from the bottom up, causing geyser-like eruptions. During Martian spring, these eruptions can...

The largest black holes in the universe... sit at the centers of almost every galaxy in the cosmos. Even the Milky Way has one, a monster at 4 million solar masses, designated as Sagittarius A*. ...[A]s far as we know, the only way to form black holes is through the deaths of massive stars. When they die, they leave behind a black hole a few times more massive than the sun. To get to supergiant status, they have to merge with other black holes and/or consume as much gas as possible, bulking up all those millions of solar masses... Either...

Explanation: In the mid 19th century, one of the first photographic technologies used to record the lunar surface was the wet-plate collodion process, notably employed by British astronomer Warren De la Rue. To capture an image, a thick, transparent mixture was used to coat a glass plate, sensitized with silver nitrate, exposed at the telescope, and then developed to create a negative image on the plate. To maintain photographic sensitivity, the entire process, from coating to exposure to developing, had to be completed before the plate dried, in a span of about 10 to 15 minutes. This modern version of...

Explanation: Familiar stars of a northern winter's night shine in this night skyview, taken near Zhangye, Gansu, China and the border with Inner Mongolia. During the early hours of December 17 Orion is near center in the single exposure that captures a fireball streaking across the sky, almost as bright as yellowish Mars shining on the right. Splitting Gemini's twin bright stars Castor and Pollux near the top of the frame, the fireball's trail and timing are consistent with the second skipping atmospheric entry of the Chang'e 5 mission's returner capsule. The returner capsule was successfully recovered after landing in...

Explanation: The South Celestial Pole is easy to spot in star trail images of the southern sky. The extension of Earth's axis of rotation to the south, it's at the center of all the southern star trail arcs. In this starry panorama streching about 60 degrees across deep southern skies the South Celestial Pole is somewhere near the middle though, flanked by bright galaxies and southern celestial gems. Across the top of the frame are the stars and nebulae along the plane of our own Milky Way Galaxy. Gamma Crucis, a yellowish giant star heads the Southern Cross near top...

Today's image is a video at link. Explanation: Yes, but have you seen a movie of Jupiter and Saturn's Great Conjunction? The featured time-lapse video was composed from a series of images taken from Thailand and shows the two giant planets as they angularly passed about a tenth of a degree from each other. The first Great Conjunction sequence shows a relative close up over five days with moons and cloud bands easily visible, followed by a second video sequence, zoomed out, over 9 days. Even though Jupiter and Saturn appeared to pass unusually close together on the sky on...

Video of December 14, 2020 eclipse shadow at link. Explanation: What does the Earth look like during a total solar eclipse? It appears dark in the region where people see the eclipse, because that's where the shadow of the Moon falls. The shadow spot rapidly shoots across the Earth at nearly 2,000 kilometers per hour, darkening locations in its path -- typically for only a few minutes -- before moving on. The featured video shows the Earth during the total solar eclipse earlier this month. The time-lapse sequence, taken from a geostationary satellite, starts with the Earth below showing night...

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...