omnianasa/nasa-apod-metadata huggingface dataset:
Millions of Stars in Omega Centauri (2024-03-28)
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.
Galileo's Europa (2024-03-29)
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 on a voyage of exploration. The spacecraft will make nearly 50 flybys, approaching to within 25 kilometers of Europa's icy surface.
Medieval Astronomy from Melk Abbey (2024-03-30)
Discovered by accident, this manuscript page provides graphical insight to astronomy in medieval times, before the Renaissance and the influence of Nicolaus Copernicus, Tycho 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.
Total Solar Eclipse Below the Bottom of the World (2024-03-31)
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.   NASA Coverage: Total Solar Eclipse of 2024 April 8
Swirling Magnetic Field around Our Galaxy's Central Black Hole (2024-04-01)
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 solar 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 creates disks and jets.    NASA Predicts:  Moon to Get in Way of Sun
Detailed View of a Solar Eclipse Corona (2024-04-02)
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  NASA Coverage: Total Solar Eclipse of 2024 April 8
Unusual Nebula Pa 30 (2024-04-03)
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.   NASA Coverage: Total Solar Eclipse of 2024 April 8
Comet Pons-Brooks at Night (2024-04-04)
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.   NASA Coverage: Total Solar Eclipse of 2024 April 8
The Solar Corona Unwrapped (2024-04-05)
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.   NASA Coverage: Total Solar Eclipse of 2024 April 8
Unwinding M51 (2024-04-06)
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, logarithmic spirals can also describe hurricanes, the tracks of subatomic particles in a bubble chamber and, of course, cauliflower.   NASA Coverage: Total Solar Eclipse of 2024 April 8
A Total Solar Eclipse over Wyoming (2024-04-07)
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 phases of the solar eclipse both before and after totality.   NASA Coverage: Tomorrow's Total Solar Eclipse
The Changing Ion Tail of Comet Pons-Brooks (2024-04-08)
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.   NASA Coverage: Today's Total Solar Eclipse  Total Eclipse Imagery: Notable Submissions to APOD
Moon's Shadow over Lake Magog (2024-04-09)
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 a 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 most of the North American continent.   Total Eclipse Imagery: Notable Submissions to APOD
Planets Around a Total Eclipse (2024-04-10)
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.   Monday's Eclipse Imagery: Notable Submissions to APOD
Eclipse in Seven (2024-04-11)
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.   Monday's Eclipse Imagery: Notable Submissions to APOD
Total Totality (2024-04-12)
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.   Solar Eclipse Imagery: Notable Submissions to APOD
Palm Tree Partial Eclipse (2024-04-13)
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.   Solar Eclipse Imagery: Notable Submissions to APOD
The Cigar Galaxy from Hubble and Webb (2024-04-15)
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.    Total Eclipse Imagery: Notable Submissions to APOD
Filaments of the Vela Supernova Remnant (2024-04-16)
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.   Monday's Eclipse Imagery: Notable Submissions to APOD
Total Eclipse and Comets (2024-04-17)
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.    Solar Eclipse Imagery: Notable Submissions to APOD
Facing NGC 1232 (2024-04-18)
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.
The Great Carina Nebula (2024-04-19)
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).
Diamonds in the Sky (2024-04-20)
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.
Moon and Smoke Rings from Mt. Etna (2024-04-22)
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 rings 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.
Contrail Shadow X (2024-04-23)
What created this giant X in the clouds? It was the shadow of contrails. 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. These contrails cast long shadows.  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.
Dragon's Egg Bipolar Emission Nebula (2024-04-24)
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.   New Mirror: APOD now available via WhatsApp
NGC 604: Giant Stellar Nursery (2024-04-25)
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.