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To some, this nebula looks like the head of a fish . However, this colorful cosmic portrait really features glowing gas and obscuring dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia . The nebula's colors were created by adopting the Hubble color palette for mapping narrowband emissions from oxygen, hydrogen, and sulfur atoms to blue, green and red colors, and further blending the data with images of the region recorded through broadband filters. Not far on the sky from the famous Double Star Cluster in Perseus, IC 1795 is itself located next to IC 1805, the Heart Nebula , as part of a complex of star forming regions that lie at the edge of a large molecular cloud. Located just over 6,000 light-years away, the larger star forming complex sprawls along the Perseus spiral arm of our Milky Way Galaxy . At that distance, IC 1795 would span about 70 light-years across. from NASA https://ift.tt/weIfsmV

The star system GK Per is known to be associated with only two of the three nebulas pictured . At 1500 light years distant, Nova Persei 1901 ( GK Persei ) was the second closest nova yet recorded. At the very center is a white dwarf star , the surviving core of a former Sun-like star. It is surrounded by the circular Firework nebula , gas that was ejected by a thermonuclear explosion on the white dwarf's surface -- a nova -- as recorded in 1901 . The red glowing gas surrounding the Firework nebula is the atmosphere that used to surround the central star. This gas was expelled before the nova and appears as a diffuse planetary nebula . The faint gray gas running across is interstellar cirrus that seems to be just passing through coincidently. In 1901, GK Per's nova became brighter than Betelgeuse . Similarly, star system T CrB is expected to erupt in a nova later this year, but we don't know exactly when nor how bright it will become. from NASA https://ift.tt/Zy...

Three bright objects satisfied seasoned stargazers of the western sky just after sunset earlier this month. The most familiar was the Moon , seen on the upper left in a crescent phase . The rest of the Moon was faintly visible by sunlight first reflected by the Earth . The bright planet Jupiter , the largest planet in the Solar System , is seen to the upper left. Most unusual was Comet 12P/Pons-Brooks , below the Moon and showing a stubby dust tail on the right but an impressive ion tail extending upwards . The featured image, a composite of several images taken consecutively at the same location and with the same camera, was taken near the village of Llers , in Spain 's Girona province . Comet Pons-Brooks passed its closest to the Sun last week and is now dimming as it moves into southern skies and returns to the outer Solar System. from NASA https://ift.tt/fyrMTxU

The Ring Nebula (M57) is more complicated than it appears through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - explores the looping filaments of glowing gas extending much farther from the nebula 's central star. This composite image includes red light emitted by hydrogen as well as visible and infrared light . The Ring Nebula is an elongated planetary nebula , a type of nebula created when a Sun -like star evolves to throw off its outer atmosphere and become a white dwarf star . The Ring Nebula is about 2,500 light-years away toward the musical constellation Lyra . from NASA https://ift.tt/yNP4njZ

If the Sun is up but the sky is dark and the horizon is bright all around, you might be standing in the Moon's shadow during a total eclipse of the Sun. In fact, the all-sky Moon shadow shown in this composited panoramic view was captured from a farm near Shirley, Arkansas, planet Earth. The exposures were made under clear skies during the April 8 total solar eclipse . For that location near the center line of the Moon's shadow track, totality lasted over 4 minutes. Along with the solar corona surrounding the silhouette of the Moon planets and stars were visible during the total eclipse phase. Easiest to see here are bright planets Venus and Jupiter, to the lower right and upper left of the eclipsed Sun. from NASA https://ift.tt/L93vIp5

In northern hemisphere spring , bright star Regulus is easy to spot above the eastern horizon. The alpha star of the constellation Leo, Regulus is the spiky star centered in this telescopic field of view . A mere 79 light-years distant, Regulus is a hot, rapidly spinning star that is known to be part of a multiple star system. Not quite lost in the glare, the fuzzy patch just below Regulus is diffuse starlight from small galaxy Leo I. Leo I is a dwarf spheroidal galaxy , a member of the Local Group of galaxies dominated by our Milky Way Galaxy and the Andromeda Galaxy ( M31 ). About 800 thousand light-years away, Leo I is thought to be the most distant of the known small satellite galaxies orbiting the Milky Way. But dwarf galaxy Leo I has shown evidence of a supermassive black hole at its center, comparable in mass to the black hole at the center of the Milky Way. from NASA https://ift.tt/rCz5fv8

Located some 3 million light-years away in the arms of nearby spiral galaxy M33 , giant stellar nursery NGC 604 is about 1,300 light-years across. That's nearly 100 times the size of the Milky Way's Orion Nebula , the closest large star forming region to planet Earth. In fact, among the star forming regions within the Local Group of galaxies, NGC 604 is second in size only to 30 Doradus, also known as the Tarantula Nebula in the Large Magellanic Cloud. Cavernous bubbles and cavities in NGC 604 fill this stunning infrared image from the James Webb Space Telescope's NIRCam . They are carved out by energetic stellar winds from the region's more than 200 hot, massive, young stars, all still in early stages of their lives . from NASA https://ift.tt/QPVD21d

How did a star form this beautiful nebula? In the middle of emission nebula NGC 6164 is an unusually massive star . The central star has been compared to an oyster's pearl and an egg protected by the mythical sky dragons of Ara . The star, visible in the center of the featured image and catalogued as HD 148937 , is so hot that the ultraviolet light it emits heats up gas that surrounds it. That gas was likely thrown off from the star previously, possibly the result of a gravitational interaction with a looping stellar companion. Expelled material might have been channeled by the magnetic field of the massive star, in all creating the symmetric shape of the bipolar nebula . NGC 6164 spans about four light years and is located about 3,600 light years away toward the southern constellation Norma . from NASA https://ift.tt/vSGI1T5

What created this giant X in the clouds? It was the shadow of contrails illuminated from below. When airplanes fly, humid engine exhaust may form water droplets that might freeze in Earth's cold upper atmosphere . These persistent streams of water and ice scatter light from the Sun above and so appear bright from below . On rare occasions, though, when the Sun is near the horizon, contrails can be lit from below. These contrails cast long shadows upwards, shadows that usually go unseen unless there is a high cloud deck. But that was just the case over Istanbul , Türkiye , earlier this month. Contrails occur all over planet Earth and, generally, warm the Earth when the trap infrared light but cool the Earth when they efficiently reflect sunlight . The image was taken by a surprised photographer in the morning on the way to work . from NASA https://ift.tt/johSzUG

Yes, but can your volcano do this? To the surprise of some, Mt. Etna emits, on occasion, smoke rings. Technically known as vortex rings , the walls of the volcano slightly slow the outside of emitted smoke puffs , causing the inside gas to move faster. A circle of low pressure develops so that the emitted puff of volcanic gas and ash loops around in a ring , a familiar geometric structure that can be surprisingly stable as it rises. Smoke ring s are quite rare and need a coincidence of the right geometry of the vent, the right speed of ejected smoke , and the relative calmness of the outside atmosphere. In the featured image taken about two weeks ago from Gangi , Sicily , Italy , multiple volcanic smoke rings are visible. The scene is shaded by the red light of a dawn Sun , while a crescent Moon is visible in the background. from NASA https://ift.tt/HnymRLI

Watch Juno zoom past Jupiter. NASA 's robotic spacecraft Juno is continuing on its now month-long, highly- elongated orbits around our Solar System's largest planet. The featured video is from perijove 16, the sixteenth time that Juno passed near Jupiter since it arrived in mid-2016. Each perijove passes near a slightly different part of Jupiter's cloud tops. This color-enhanced video has been digitally composed from 21 JunoCam still images, resulting in a 125-fold time-lapse. The video begins with Jupiter rising as Juno approaches from the north. As Juno reaches its closest view -- from about 3,500 kilometers over Jupiter's cloud tops -- the spacecraft captures the great planet in tremendous detail. Juno passes light zones and dark belts of clouds that circle the planet, as well as numerous swirling circular storms, many of which are larger than hurricanes on Earth . As Juno moves away, the remarkable dolphin-shaped cloud is visible. After the perijove, Ju...

When the dark shadow of the Moon raced across North America on April 8, sky watchers along the shadow's narrow central path were treated to a total solar eclipse. During the New Moon's shadow play diamonds glistened twice in the eclipse-darkened skies . The transient celestial jewels appeared immediately before and after the total eclipse phase. That's when the rays of a vanishing and then emerging sliver of solar disk are just visible behind the silhouetted Moon's edge, creating the appearance of a shiny diamond set in a dark ring. This dramatic timelapse composite from north-central Arkansas captures both diamond ring moments of this total solar eclipse . The diamond rings are separated by the ethereal beauty of the solar corona visible during totality. from NASA https://ift.tt/VX1yM0N

A jewel of the southern sky , the Great Carina Nebula is more modestly known as NGC 3372. One of our Galaxy's largest star forming regions, it spans over 300 light-years. Like the smaller, more northerly Great Orion Nebula , the Carina Nebula is easily visible to the unaided eye. But at a distance of 7,500 light-years it lies some 5 times farther away. This stunning telescopic view reveals remarkable details of the region's glowing filaments of interstellar gas and obscuring cosmic dust clouds. The Carina Nebula is home to young, extremely massive stars, including the still enigmatic variable Eta Carinae , a star with well over 100 times the mass of the Sun. Eta Carinae is the bright star above the central dark notch in this field and left of the dusty Keyhole Nebula (NGC 3324). from NASA https://ift.tt/9gFuRIT

From our vantage point in the Milky Way Galaxy , we see NGC 1232 face-on. Nearly 200,000 light-years across, the big, beautiful spiral galaxy is located some 47 million light-years away in the flowing southern constellation of Eridanus. This sharp, multi-color, telescopic image of NGC 1232 includes remarkable details of the distant island universe. From the core outward, the galaxy's colors change from the yellowish light of old stars in the center to young blue star clusters and reddish star forming regions along the grand, sweeping spiral arms. NGC 1232's apparent, small, barred-spiral companion galaxy is cataloged as NGC 1232A. Distance estimates place it much farther though, around 300 million light-years away, and unlikely to be interacting with NGC 1232 . Of course, the prominent bright star with the spiky appearance is much closer than NGC 1232 and lies well within our own Milky Way. from NASA https://ift.tt/aXoLFmC

Not one, but two comets appeared near the Sun during last week's total solar eclipse . The expected comet was Comet 12P/Pons-Brooks , but it was disappointingly dimmer than many had hoped. However, relatively unknown Comet SOHO-5008 also appeared in long duration camera exposures. This comet was the 5008th comet identified on images taken by ESA & NASA 's Sun-orbiting SOHO spacecraft . Likely much smaller, Comet SOHO-5008 was a sungrazer which disintegrated within hours as it passed too near the Sun . The featured image is not only unusual for capturing two comets during an eclipse, but one of the rare times that a sungrazing comet has been photographed from the Earth's surface. Also visible in the image is the sprawling corona of our Sun and the planets Mercury (left) and Venus (right). Of these planets and comets, only Venus was easily visible to millions of people in the dark shadow of the Moon that crossed North America on April 8. from NASA https:...

The explosion is over, but the consequences continue. About eleven thousand years ago, a star in the constellation of Vela could be seen to explode , creating a strange point of light briefly visible to humans living near the beginning of recorded history . The outer layers of the star crashed into the interstellar medium , driving a shock wave that is still visible today. The featured image captures some of that filamentary and gigantic shock in visible light . As gas flies away from the detonated star, it decays and reacts with the interstellar medium, producing light in many different colors and energy bands. Remaining at the center of the Vela Supernova Remnant is a pulsar , a star as dense as nuclear matter that spins around more than ten times in a single second. from NASA https://ift.tt/14bq0fA

Something strange happened to this galaxy, but what? Known as the Cigar Galaxy and cataloged as M82 , red glowing gas and dust are being cast out from the center. Although this starburst galaxy was surely stirred up by a recent pass near its neighbor , large spiral galaxy M81 , this doesn't fully explain the source of the red-glowing outwardly expanding gas and dust . Evidence indicates that this material is being driven out by the combined emerging particle winds of many stars, together creating a galactic superwind . In the featured images , a Hubble Space Telescope image in visible light is shown on the left, while a James Webb Space Telescope image of the central region in infrared light is shown on the right. Detailed inspection of the new Webb image shows, unexpectedly, that this red-glowing dust is associated with hot plasma . Research into the nature of this strange nearby galaxy will surely continue. from NASA https://ift.tt/DhPoLyn

How does a total solar eclipse end? Yes, the Moon moves out from fully blocking the Sun , but in the first few seconds of transition, interesting things appear . The first is called a diamond ring . Light might stream between mountains or through relative lowlands around the Moon's edge , as seen from your location, making this sudden first light, when combined with the corona that surrounds the Moon , look like a diamond ring . Within seconds other light streams appear that are called, collectively, Bailey's beads . In the featured video , it may seem that the pink triangular prominence on the Sun is somehow related to where the Sun begins to reappear, but it is not. Observers from other locations saw Bailey's beads emerge from different places around the Moon, away from the iconic triangular solar prominence visible to all. The video was captured with specialized equipment from New Boston , Texas , USA on April 8, 2024. from NASA https://ift.tt/sA8HbWX

Only those along the narrow track of the Moon's shadow on April 8 saw a total solar eclipse. But most of North America still saw a partial eclipse of the Sun. From Clearwater, Florida, USA this single snapshot captured multiple images of that more widely viewed celestial event without observing the Sun directly. In the shade of a palm tree, criss-crossing fronds are projecting recognizable eclipse images on the ground, pinhole camera style . In Clearwater the maximum eclipse phase was about 53 percent. from NASA https://ift.tt/3nejFw2

Baily's beads often appear at the boundaries of the total phase of an eclipse of the Sun. Pearls of sunlight still beaming through gaps in the rugged terrain along the lunar limb silhouette, their appearance is recorded in this dramatic timelapse composite. The series of images follows the Moon's edge from beginning through the end of totality during April 8's solar eclipse from Durango, Mexico . They also capture pinkish prominences of plasma arcing high above the edge of the active Sun. One of the first places in North America visited by the Moon's shadow on April 8, totality in Durango lasted about 3 minutes and 46 seconds. from NASA https://ift.tt/392jUXp

Start at the upper left above and you can follow the progress of April 8's total eclipse of the Sun in seven sharp, separate exposures. The image sequence was recorded with a telescope and camera located within the narrow path of totality as the Moon's shadow swept across Newport, Vermont, USA. At center is a spectacular view of the solar corona . The tenuous outer atmosphere of the Sun is only easily visible to the eye in clear dark skies during the total eclipse phase. Seen from Newport , the total phase for this solar eclipse lasted about 3 minutes and 26 seconds. from NASA https://ift.tt/GCcHvud

What wonders appear when the Moon blocks the Sun? For many eager observers of Monday’s total eclipse of the Sun, the suddenly dark sky included the expected corona and two (perhaps surprise) planets: Venus and Jupiter . Normally, in recent days, Venus is visible only in the morning when the Sun and Jupiter are below the horizon, while Jupiter appears bright only in the evening. On Monday, though, for well-placed observers, both planets became easily visible during the day right in line with the totally eclipsed Sun . This line was captured Monday afternoon in the featured image from Mount Nebo , Arkansas , USA , along with a line of curious observers — and a picturesque tree . from NASA https://ift.tt/MsHiI5z

Captured in this snapshot, the shadow of the Moon came to Lake Magog, Quebec, North America, planet Earth on April 8. For the lakeside eclipse chasers, the much anticipated total solar eclipse was spectacle to behold in briefly dark, but clear skies. Of course Lake Magog was one of the last places to be visited by the Moon's shadow. The narrow path of totality for the 2024 total solar eclipse swept from Mexico's Pacific Coast north and eastward through the US and Canada. But a partial eclipse was visible across the entire North American continent. from NASA https://ift.tt/rmo6G8C

How does a comet tail change? It depends on the comet. The ion tail of Comet 12P/Pons–Brooks has been changing markedly, as detailed in the featured image sequenced over nine days from March 6 to 14 (top to bottom). On some days, the comet's ion tail was relatively long and complex, but not every day. Reasons for tail changes include the rate of ejection of material from the comet's nucleus , the strength and complexity of the passing solar wind , and the rotation rate of the comet . Over the course of a week, apparent changes even include a change of perspective from the Earth. In general, a comet's ion tail will point away from the Sun , as gas expelled is pushed out by the Sun's wind . Today, Pons-Brooks may become a rare comet suddenly visible in the middle of the day for those able to see the Sun totally eclipsed by the Moon . from NASA https://ift.tt/HcjNEVa

Will the sky be clear enough to see the eclipse? This question is already on the minds of many North Americans hoping to see tomorrow's solar eclipse . This question was also on the mind of many people attempting to see the total solar eclipse that crossed North America in August 2017 . Then, the path of total darkness shot across the mainland of the USA from coast to coast , from Oregon to South Carolina -- but, like tomorrow's event, a partial eclipse occurred above most of North America . Unfortunately, in 2017, many locations saw predominantly clouds . One location that did not was a bank of the Green River Lakes , Wyoming . Intermittent clouds were far enough away to allow the center image of the featured composite sequence to be taken, an image that shows the corona of the Sun extending out past the central dark Moon that blocks our familiar Sun . The surrounding images show the partial phase s of the solar eclipse both before and after totality. from NASA https:...

The arms of a grand design spiral galaxy 60,000 light-years across are unwound in this digital transformation of the magnificent 2005 Hubble Space Telescope portrait of M51 . In fact, M51 is one of the original spiral nebulae, its winding arms described by a mathematical curve known as a logarithmic spiral , a spiral whose separation grows in a geometric way with increasing distance from the center. Applying logarithms to shift the pixel coordinates in the Hubble image relative to the center of M51 maps the galaxy's spiral arms into diagonal straight lines. The transformed image dramatically shows the arms themselves are traced by star formation, lined with pinkish starforming regions and young blue star clusters. Companion galaxy NGC 5195 (top) seems to alter the track of the arm in front of it though, and itself remains relatively unaffected by this unwinding of M51. Also known as the spira mirabilis , logarthimic spirals can be found in nature on all scales. For example, logar...

Changes in the alluring solar corona are detailed in this creative composite image mapping the dynamic outer atmosphere of the Sun during two separate total solar eclipses. Unwrapped from the complete circle of the eclipsed Sun's edge to a rectangle and mirrored, the entire solar corona is shown during the 2017 eclipse (bottom) seen from Jackson Hole, Wyoming, and the 2023 eclipse from Exmouth, Western Australia. While the 2017 eclipse was near a minimum in the Sun's 11 year activity cycle , the 2023 eclipse was closer to solar maximum. The 2023 solar corona hints at the dramatically different character of the active Sun, with many streamers and pinkish prominences arising along the solar limb. Of course, the solar corona is only easily visible to the eye while standing in the shadow of the Moon. from NASA https://ift.tt/Tv4cj9O

In dark evening skies over June Lake , northern hemisphere, planet Earth, Comet 12P/Pons-Brooks stood just above the western horizon on March 30. Its twisted turbulent ion tail and diffuse greenish coma are captured in this two degree wide telescopic field of view along with bright yellowish star Hamal also known as Alpha Arietis . Now Pons-Brooks has moved out of the northern night though, approaching perihelion on April 21. On April 8 you might still spot the comet in daytime skies. But to do it, you will have to stand in the path of totality and look away from the spectacle of an alluring solar corona and totally eclipsed Sun. from NASA https://ift.tt/4OURhIL

What created this unusual celestial firework? The nebula, dubbed Pa 30 , appears in the same sky direction now as a bright " guest star " did in the year 1181 . Although Pa 30's filaments look similar to that created by a nova (for example GK Per ), and a planetary nebula (for example NGC 6751 ), some astronomers now propose that it was created by a rare type of supernova : a thermonuclear Type Iax, and so is (also) named SN 1181 . In this model , the supernova was not the result of the detonation of a single star, but rather a blast that occurred when two white dwarf stars spiraled together and merged. The blue dot in the center is hypothesized to be a zombie star , the remnant white dwarf that somehow survived this supernova -level explosion. The featured image combines images and data obtained with infrared ( WISE ), visible ( MDM , Pan-STARRS ), and X-ray ( Chandra , XMM ) telescopes. Future observations and analyses may tell us more . from NASA https://ift....

Only in the fleeting darkness of a total solar eclipse is the light of the solar corona easily visible. Normally overwhelmed by the bright solar disk, the expansive corona , the sun's outer atmosphere , is an alluring sight. But the subtle details and extreme ranges in the corona's brightness, although discernible to the eye, are notoriously difficult to photograph. Pictured here , however, using multiple images and digital processing, is a detailed image of the Sun's corona taken during the April 20, 2023 total solar eclipse from Exmouth , Australia. Clearly visible are intricate layers and glowing caustics of an ever changing mixture of hot gas and magnetic fields . Bright looping prominences appear pink just around the Sun's limb . A similar solar corona might be visible through clear skies in a narrow swath across the North America during the total solar eclipse that occurs just six days from today from NASA https://ift.tt/wxZOnD9

What's happening to the big black hole in the center of our galaxy? It is sucking in matter from a swirling disk -- a disk that is magnetized , it has now been confirmed. Specifically, the black hole's accretion disk has recently been seen to emit polarized light , radiation frequently associated with a magnetized source . Pictured here is a close-up of Sgr A*, our Galaxy's central black hole , taken by radio telescopes around the world participating in the Event Horizon Telescope (EHT) Collaboration . Superposed are illustrative curved lines indicating polarized light likely emitted from swirling magnetized gas that will soon fall into the 4+ million mass central black hole . The central part of this image is likely dark because little light-emitting gas is visible between us and the dark event horizon of the black hole. Continued EHT monitoring of this and M87's central black hole may yield new clues about the gravity of black holes and how infalling matter ...

In late 2021 there was a total solar eclipse visible only at the end of the Earth. To capture the unusual phenomenon , airplanes took flight below the clouded seascape of Southern Ocean . The featured image shows one relatively spectacular capture where the bright spot is the outer corona of the Sun and the eclipsing Moon is seen as the dark spot in the center. A wing and engine of the airplane are visible across the left and bottom of the image, while another airplane observing the eclipse is visible on the far left. The dark area of the sky surrounding the eclipsed Sun is called a shadow cone . It is dark because you are looking down a long corridor of air shadowed by the Moon. A careful inspection of the eclipsed Sun will reveal the planet Mercury just to the right. You won't have to travel to the end of the Earth to see the next total solar eclipse . The total eclipse path will cross North America on 2024 April 8 , just over one week from today. from NASA https://i...

Discovered by accident, this manuscript page provides graphical insight to astronomy in medieval times, before the Renaissance and the influence of Nicolaus Copernicus , Tycho de Brahe , Johannes Kepler , and Galileo . The intriguing page is from lecture notes on astronomy compiled by the monk Magister Wolfgang de Styria before the year 1490. The top panels clearly illustrate the necessary geometry for a lunar (left) and solar eclipse in the Earth-centered Ptolemaic system . At lower left is a diagram of the Ptolemaic view of the Solar System with text at the upper right to explain the movement of the planets according to Ptolemy's geocentric model. At the lower right is a chart to calculate the date of Easter Sunday in the Julian calendar. The illustrated manuscript page was found at historic Melk Abbey in Austria. from NASA https://ift.tt/QVZIctP

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. The Juno spacecraft currently in Jovian orbit has also made repeated flybys of the water world, returning images along with data exploring Europa's habitability . This October will see the launch of the NASA's Europa Clipper ...

Globular star cluster Omega Centauri , also known as NGC 5139, is 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about 150 light-years in diameter. It's the largest and brightest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of a small galaxy merging with the Milky Way. With a yellowish hue , Omega Centauri's red giant stars are easy to pick out in this sharp, color telescopic view . from NASA https://ift.tt/hA50PNc

Almost every object in the featured photograph is a galaxy. The Coma Cluster of Galaxies pictured here is one of the densest clusters known - it contains thousands of galaxies . Each of these galaxies houses billions of stars - just as our own Milky Way Galaxy does. Although nearby when compared to most other clusters , light from the Coma Cluster still takes hundreds of millions of years to reach us. In fact, the Coma Cluster is so big it takes light millions of years just to go from one side to the other. Most galaxies in Coma and other clusters are ellipticals , while most galaxies outside of clusters are spirals . The nature of Coma's X-ray emission is still being investigated . from NASA https://ift.tt/wb6oc4U

Comet Pons-Brooks has quite a tail to tell. First discovered in 1385 , this erupting dirty snowball loops back into our inner Solar System every 71 years and, this time, is starting to put on a show for deep camera exposures. In the featured picture , the light blue stream is the ion tail which consists of charged molecule s pushed away from the comet's nucleus by the solar wind. The ion tail, shaped by the Sun's wind and the comet's core's rotation , always points away from the Sun. Comet 12P/Pons–Brooks is now visible with binoculars in the early evening sky toward the northwest, moving perceptibly from night to night. The frequently flaring comet is expected to continue to brighten, on the average, and may even become visible with the unaided eye -- during the day -- to those in the path of totality of the coming solar eclipse on April 8 . from NASA https://ift.tt/4OoywLP

Here is what the Earth looks like during a solar eclipse . The shadow of the Moon can be seen darkening part of Earth . This shadow moved across the Earth at nearly 2000 kilometers per hour. Only observers near the center of the dark circle see a total solar eclipse - others see a partial eclipse where only part of the Sun appears blocked by the Moon . This spectacular picture of the 1999 August 11 solar eclipse was one of the last ever taken from the Mir space station . The two bright spots that appear on the upper left are thought to be Jupiter and Saturn . Mir was deorbited in a controlled re-entry in 2001. A new solar eclipse will occur over North America in about two weeks. from NASA https://ift.tt/KNDhIU4

This close-up from the Mars Reconnaissance Orbiter's HiRISE camera shows weathered craters and windblown deposits in southern Acidalia Planitia . A striking shade of blue in standard HiRISE image colors, to the human eye the area would probably look grey or a little reddish. But human eyes have not gazed across this terrain, unless you count the eyes of NASA astronauts in the scifi novel The Martian by Andy Weir. The novel chronicles the adventures of Mark Watney, an astronaut stranded at the fictional Mars mission Ares 3 landing site corresponding to the coordinates of this cropped HiRISE frame. For scale Watney's 6-meter-diameter habitat at the site would be about 1/10th the diameter of the large crater. Of course , the Ares 3 landing coordinates are only about 800 kilometers north of the (real life) Carl Sagan Memorial Station , the 1997 Pathfinder landing site . from NASA https://ift.tt/MfvUH8r

A tiny moon with a scary name , Phobos emerges from behind the Red Planet in this timelapse sequence from the Earth-orbiting Hubble Space Telescope . Over 22 minutes the 13 separate exposures were captured near the 2016 closest approach of Mars to planet Earth. Martians have to look to the west to watch Phobos rise, though. The small moon is closer to its parent planet than any other moon in the Solar System, about 3,700 miles (6,000 kilometers) above the Martian surface . It completes one orbit in just 7 hours and 39 minutes. That's faster than a Mars rotation, which corresponds to about 24 hours and 40 minutes. So on Mars, Phobos can be seen to rise above the western horizon 3 times a day. Still, Phobos is doomed . from NASA https://ift.tt/LZaxdvU

This popular group leaps into the early evening sky around the March equinox and the northern hemisphere spring . Famous as the Leo Triplet , the three magnificent galaxies found in the prominent constellation Leo gather here in one astronomical field of view. Crowd pleasers when imaged with even modest telescopes, they can be introduced individually as NGC 3628 (left), M66 (bottom right), and M65 (top). All three are large spiral galaxies but tend to look dissimilar, because their galactic disks are tilted at different angles to our line of sight. NGC 3628 , also known as the Hamburger Galaxy, is temptingly seen edge-on, with obscuring dust lanes cutting across its puffy galactic plane. The disks of M66 and M65 are both inclined enough to show off their spiral structure. Gravitational interactions between galaxies in the group have left telltale signs, including the tidal tails and warped, inflated disk of NGC 3628 and the drawn out spiral arms of M66. This gorgeous view of the ...

Across the heart of the Virgo Galaxy Cluster lies a string of galaxies known as Markarian's Chain . Prominent in Markarian's Chain are these two interacting galaxies , NGC 4438 (left) and NGC 4435 - also known as The Eyes. About 50 million light-year s away, the two galaxies appear to be about 100,000 light-years apart in this sharp close-up , but have likely approached to within an estimated 16,000 light-years of each other in their cosmic past . Gravitational tides from the close encounter have ripped away at their stars, gas, and dust. The more massive NGC 4438 managed to hold on to much of the material torn out in the collision , while material from the smaller NGC 4435 was more easily lost . The remarkably deep image of this crowded region of the universe also includes many more distant background galaxies . from NASA https://ift.tt/1RFyVY9

A bright comet will be visible during next month's total solar eclipse. This very unusual coincidence occurs because Comet 12P/Pons-Brooks 's return to the inner Solar System places it by chance only 25 degrees away from the Sun during Earth's April 8 total solar eclipse . Currently the comet is just on the edge of visibility to the unaided eye, best visible with binoculars in the early evening sky toward the constellation of the Fish ( Pisces ). Comet Pons-Brooks , though, is putting on quite a show for deep camera images even now. The featured image is a composite of three very specific colors, showing the comet's ever-changing ion tail in light blue, its outer coma in green, and highlights some red-glowing gas around the coma in a spiral . The spiral is thought to be caused by gas being expelled by the slowly rotating nucleus of the giant iceberg comet. Although it is always difficult to predict the future brightness of comets, Comet Pons-Brook has been p...

The southern winter Milky Way sprawls across this night skyscape. Looking due south, the webcam view was recorded near local midnight on March 11 in dry, dark skies over the central Chilean Atacama desert. Seen below the graceful arc of diffuse starlight are satellite galaxies of the mighty Milky Way, also known as the Large and Small Magellanic clouds . In the foreground is the site of the European Southern Observatory's 40-metre-class Extremely Large Telescope (ELT). Under construction at the 3000 metre summit of Cerro Armazones , the ELT is on track to become planet Earth's biggest Eye on the Sky. from NASA https://ift.tt/rRH2h7p

Big, beautiful spiral galaxy NGC 1055 is a dominant member of a small galaxy group a mere 60 million light-years away toward the aquatically intimidating constellation Cetus . Seen edge-on, the island universe spans over 100,000 light-years, a little larger than our own Milky Way galaxy. The colorful, spiky stars decorating this cosmic portrait of NGC 1055 are in the foreground, well within the Milky Way. But the telltale pinkish star forming regions are scattered through winding dust lanes along the distant galaxy's thin disk. With a smattering of even more distant background galaxies, the deep image also reveals a boxy halo that extends far above and below the central bulge and disk of NGC 1055. The halo itself is laced with faint, narrow structures, and could represent the mixed and spread out debris from a satellite galaxy disrupted by the larger spiral some 10 billion years ago . from NASA https://ift.tt/9Uk10aB

What phase of the Moon is 3.14 radians from the Sun? The Full Moon, of course. Even though the Moon might look full for several days, the Moon is truly at its full phase when it is Pi radians (aka 180 degrees) from the Sun in ecliptic longitude. That's opposite the Sun in planet Earth's sky. Rising as the Sun set on March 9, 2020, only an hour or so after the moment of its full phase, this orange tinted and slightly flattened Moon still looked full. It was photographed opposite the setting Sun from Teide National Park on the Canary Island of Tenerife. Also opposite the setting Sun, seen from near the Teide volcano peak about 3,500 meters above sea level, is the mountain's rising triangular shadow extending into Earth's dense atmosphere. Below the distant ridge line on the left are the white telescope domes of Teide Observatory . Again Pi radians from the Sun, on March 25 the Full Moon will dim slightly as it glides through Earth's outer shadow in a penumbral l...

A broad expanse of glowing gas and dust presents a bird-like visage to astronomers from planet Earth , suggesting its popular moniker: the Seagull Nebula . This portrait of the cosmic bird covers a 1.6-degree wide swath across the plane of the Milky Way, near the direction of Sirius , the alpha star of the constellation of the Big Dog ( Canis Major ). Of course, the region includes objects with other catalog designations: notably NGC 2327 , a compact, dusty emission and reflection nebula with an embedded massive star that forms the bird's head . Dominated by the reddish glow of atomic hydrogen , the complex of gas and dust clouds with bright young stars spans over 100 light-years at an estimated 3,800 light-year distance. from NASA https://ift.tt/3WYdzaR

What's that over the horizon? What may look like a strangely nearby galaxy is actually a normal rocket's exhaust plume -- but unusually backlit. Although the SpaceX Falcon 9 rocket was launched from Cape Canaveral in Florida , USA , its burned propellant was visible over a much wider area, with the featured photograph being taken from Akureyri , Iceland . The huge spaceship was lifted off a week ago, and the resulting spectacle was captured soon afterward with a single 10-second smartphone exposure, before it quickly dissipated. Like noctilucent clouds , the plume's brightness is caused by the Twilight Effect , where an object is high enough to be illuminated by the twilight Sun, even when the observer on the ground experiences the darkness of night. The spiral shape is likely caused by high winds pushing the expelled gas into the shape of a corkscrew , which, when seen along the trajectory, looks like a spiral . Stars and faint green and red aurora appear in the...

What glows in the night? This night featured a combination of usual and unusual glows. Perhaps the most usual glow was from the Moon , a potentially familiar object. The full Moon's nearly vertical descent results from the observer being near Earth's equator . As the Moon sets, air and aerosol s in Earth's atmosphere preferentially scatter out blue light, making the Sun-reflecting satellite appear reddish when near the horizon. Perhaps the most unusual glow was from the bioluminescent plankton , likely less familiar objects. These microscopic creatures glow blue, it is thought, primarily to surprise and deter predators . In this case, the glow was caused primarily by plankton-containing waves crashing onto the beach. The image was taken on Soneva Fushi Island , Maldives just over one year ago. from NASA https://ift.tt/cOTNLJ5

Would you go to the end of the world to see a total eclipse of the Sun? If you did, would you be surprised to find someone else there already? In 2003, the Sun , the Moon, Antarctica, and two photographers all lined up in Antarctica during an unusual total solar eclipse . Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon . One of the treasures collected was the featured picture -- a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse. As the image was taken, both the Moon and the Sun peeked together over an Antarctic ridge. In the sudden darkness , the magnificent corona of the Sun became visible around the Moon. Quite by accident, another photographer was caught in one of the images checking his video camera. Visible to his left are an equipment bag and a collapsible cha...