omnianasa/nasa-apod-metadata huggingface dataset:
Lightning Eclipse from the Planet of the Goats (2011-06-18)
Thunderstorms almost spoiled this view of the spectacular June 15 total lunar eclipse. Instead, storm clouds parted for 10 minutes during the total eclipse phase and lightning bolts contributed to the dramatic sky. Captured with a 30 second exposure the scene also inspired what, in the 16 year history of Astronomy Picture of the Day, the editor considers may be the best title yet for a picture (title credit to Chris K.). Of course, the lightning reference clearly makes sense, and the shadow play of the dark lunar eclipse was widely viewed across planet Earth in Europe, Africa, Asia, and Australia. The picture itself, however, was shot from the Greek island of Ikaria at Pezi. That area is known as "the planet of the goats" because of the rough terrain and strange looking rocks.
The Regolith of Asteroid Eros (2011-06-19)
From fifty kilometers above asteroid Eros, the surface inside one of its largest craters appears covered with an unusual substance: regolith.  The thickness and composition of the surface dust that is regolith remains a topic of much research.  Much of the regolith on 433 Eros was probably created by numerous small impacts during its long history.  In this representative-color view taken by the robot spacecraft NEAR-SHOEMAKER that orbited Eros in 2000 and 2001, brown areas indicate regolith that has been chemically altered by exposure to the solar wind during micrometeorite impacts.  White areas are thought to have undergone relatively less exposure.  The boulders visible inside the crater appear brown, indicating either that they are old enough to have a surface itself tanned by the solar wind, or that they have somehow become covered with some dark surface dust. This July, NASA's Dawn spacecraft will orbit giant main belt asteroid Vesta.
Last Roll Out of a NASA Space Shuttle (2011-06-20)
In the final move of its kind, NASA's space shuttle Atlantis was photographed earlier this month slowly advancing toward Launch Pad 39A, where it is currently scheduled for a July launch to the International Space Station. The mission, designated STS-135, is the 135th and last mission for a NASA space shuttle. Atlantis and its four-person crew will be carrying, among other things, the Multi-Purpose Logistics Module Raffaello to bring key components and supplies to the ISS. Pictured above, the large Shuttle Crawler Transporter rolls the powerful orbiter along the five-kilometer long road at less than two kilometers per hour.  Over 15,000 spectators, some visible on the right, were on hand for the historic roll out.
Eclipsed Moonlight (2011-06-21)
A celestial prelude to today's solstice, the June 15 total lunar eclipse was one of the longest in recent years. It was also one of the darkest, but not completely dark. Even during totality, a somber, red lunar disk could be seen in the starry night sky, reflecting reddened light falling on to its surface. Seen from a lunar perspective, the ruddy illumination is from all the sunsets and sunrises around the edges of a silhouetted Earth. In this sharp portrait of the eclipsed Moon from Granada, Spain, the Moon's edge reflects a bluish tinge as well as it emerges from Earth's umbral shadow. The bluer light is still filtered through Earth's atmosphere, but originates in rays of sunlight passing through layers high in the upper stratosphere. That light is colored by ozone that absorbs red light and transmits bluer hues.
MESSENGER's Degas View (2011-06-22)
Now imaging inner planet Mercury from orbit, the MESSENGER spacecraft wide angle camera has returned this impressive color view of Degas Crater, with a full resolution of 90 meters per pixel. Named for the impressionist painter, the 52 kilometer diameter crater is also shown in an inset context image from the Mariner 10 flyby mission in the mid 1970s. In MESSENGER's view, the crater floor is seen to be filled with an intricate series of cracks, formed as the molten surface resulting from the impact cooled and contracted. Starkly bright, patchy deposits, suggesting compositional differences and freshly exposed material, standout around the crater's central peaks and walls. Details of similar bright deposits are seen in even higher resolution images from MESSENGER.
Stereo Helene (2011-06-23)
Get out your red/blue glasses and float next to Helene, small, icy moon of Saturn. Appropriately named, Helene is one of four known Trojan moons, so called because it orbits at a Lagrange point. A Lagrange point is a gravitationally stable position near two massive bodies, in this case Saturn and larger moon Dione. In fact, irregularly shaped ( about 36 by 32 by 30 kilometers) Helene orbits at Dione's leading Lagrange point while brotherly ice moon Polydeuces follows at Dione's trailing Lagrange point. The sharp stereo anaglyph was constructed from two Cassini images (N00172886, N00172892) captured during the recent close flyby. It shows part of the Saturn-facing hemisphere of Helene mottled with craters and gully-like features.   Technorati Claim Code: 9CN8HGUDKM3X
The Big Dipper (2011-06-24)
The best known asterism in northern skies, The Big Dipper is easy to recognize, though some might see The Plough. Either way, the star names and the familiar outlines will appear in this thoughtfully composed 24 frame mosaic when you slide your cursor over the image. Dubhe, alpha star of the dipper's parent constellation Ursa Major is at the upper right. Together with beta star Merak below, the two form a line pointing the way to Polaris and the North Celestial Pole off the top edge of the field. Notable too in skygazing lore Mizar, second star from the left in the dipper's handle, forms a vision-testing visual double star with apparently close Alcor. Also identified in the famous star field are Messier catalog objects. Download the higher resolution image to hunt for exquisite views of some of Messier's distant spiral galaxies and a more local owl.   What was that?: Help identify a mystery flash seen on Mauna Kea
Eclipse over the Acropolis (2011-06-25)
The total phase of the June 15 lunar eclipse lasted an impressive 100 minutes. Its entire duration is covered in this composite of a regular sequence of digital camera exposures, tracking the dark lunar disk as it arced above the Acropolis in Athens, Greece. In fact, around 270 BCE Greek astronomer Aristarchus also tracked the duration of lunar eclipses, though without the benefit of digital clocks and cameras. Still, using geometry, he devised a simple and impressively accurate way to calculate the Moon's distance, in terms of the radius of planet Earth, from the eclipse duration. A more modern Greek astronomer, Elias Politis titled this eclipse duration study and the accompanying youtube timelapse video "Acropoclipse".   What was that?: Help identify a mystery flash seen on Mauna Kea
NGC 3132: The Eight Burst Nebula (2011-06-26)
It's the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula.  Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun.  In this representative color picture, the hot blue pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Although photographed to explore unusual symmetries, it's the asymmetries that help make this planetary nebula so intriguing.  Neither the unusual shape of the surrounding cooler shell nor the structure and placements of the cool filamentary dust lanes running across NGC 3132 are well understood.
Stars and Dust Across Corona Australis (2011-06-27)
Cosmic dust clouds sprawl across a rich field of stars in this sweeping telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Probably less than 500 light-years away and effectively blocking light from more distant, background stars in the Milky Way, the densest part of the dust cloud is about 8 light-years long. At its tip (upper right) is a group of lovely reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. A characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The smaller yellowish nebula (NGC 6729) surrounds young variable star R Coronae Australis. Magnificent globular star cluster NGC 6723 is toward the upper right corner of the view. While NGC 6723 appears to be part of the group, it actually lies nearly 30,000 light-years away, far beyond the Corona Australis dust clouds.
Stardust and Betelgeuse (2011-06-28)
An expansive nebula of dust is seen to surround red supergiant star Betegeuse in this remarkable high resolution composite, an infrared VLT image from the European Southern Observatory. Betelgeuse itself is outlined by the small, central red circle. If found in our own solar system its diameter would almost encompass the orbit of Jupiter. But the larger envelope of circumstellar dust extends some 60 billion kilometers into space, equivalent to about 400 times the Earth-Sun distance. The dust is likely formed as the swollen atmosphere of the supergiant sheds material into space, a final phase in the evolution of a massive star. Mixing with the interstellar medium, the dust could ultimately form rocky terrestrial planets like Earth. The central bright portion of the outer image has been masked to reveal fainter extended structures. The field of view is 5.63 arcseconds across.
Abell 2744: Pandora's Cluster of Galaxies (2011-06-29)
Why is this cluster of galaxies so jumbled? Far from a smooth distribution, Abell 2744 not only has knots of galaxies, but the X-ray emitting hot gas (colored red) in the cluster appears distributed differently than the dark matter. The dark matter, taking up over 75 percent of the cluster mass and colored blue in the above image, was inferred by that needed to create the distortion of background galaxies by gravitational lensing. The jumble appears to result from the slow motion collision of at least four smaller galaxy clusters over the past few billion years. The above picture combines optical images from the Hubble Space Telescope and the Very Large Telescope with X-ray images from the Chandra X-Ray Observatory. Abell 2744, dubbed Pandora's cluster, spans over two million light years and can best be seen with a really large telescope toward the constellation of the Sculptor.
Star Factory Messier 17 (2011-06-30)
Sculpted by stellar winds and radiation, the star factory known as Messier 17 lies some 5,500 light-years away in the nebula-rich constellation Sagittarius. At that distance, this degree wide field of view spans almost 100 light-years, courtesy of the European Southern Observatory's new VLT Survey Telescope and OmegaCAM. The sharp, false color image includes both optical and infrared data, following faint details of the region's gas and dust clouds against a backdrop of central Milky Way stars. Stellar winds and energetic light from hot, massive stars formed from M17's stock of cosmic gas and dust have slowly carved away at the remaining interstellar material producing the cavernous appearance and undulating shapes. M17 is also known as the Omega Nebula or the Swan Nebula.
VAR! (2011-07-01)
In the 1920s, examining photographic plates from the Mt. Wilson Observatory's 100 inch telescope, Edwin Hubble determined the distance to the Andromeda Nebula, decisively demonstrating the existence of other galaxies far beyond the Milky Way. His notations are evident on the historic plate image inset at the lower right, shown in context with ground based and Hubble Space Telescope images of the region made nearly 90 years later. By comparing different plates, Hubble searched for novae, stars which underwent a sudden increase in brightness. He found several on this plate, indicating their position with lines and an "N".  Later, discovering that the one near the upper right corner was actually a type of variable star known as a cepheid, he crossed out the "N" and wrote "VAR!". Thanks to the work of Harvard astronomer Henrietta Leavitt, cepheids, regularly varying pulsating stars, could be used as standard candle distance indicators. Identifying such a star allowed Hubble to show that Andromeda was not a small cluster of stars and gas within our own galaxy, but a large galaxy in its own right at a substantial distance from the Milky Way. Hubble's discovery is responsible for establishing our modern concept of a Universe filled with galaxies.
Moon and Venus at Dawn (2011-07-02)
Brilliant Venus and a thin crescent Moon stood together above the eastern horizon just before sunrise on June 30. The lovely celestial pairing is captured in this colorful twilight skyview overlooking a reservoir near Izmir, Turkey. For some, the close conjunction could be viewed as a daylight occultation. While Venus is nearing the end of its latest performance as planet Earth's morning star, the old lunar cresent, about 24 hours from its New Moon phase, was also bidding farewell for now to the dawn. In fact, for the next two nights a young Moon can be spotted just after sunset. Look for a thin sunlit sliver close to the western horizon, not far from bright planet Mercury.
Alpha Centauri: The Closest Star System (2011-07-03)
The closest star system to the Sun is the Alpha Centauri system. Of the three stars in the system, the dimmest -- called Proxima Centauri -- is actually the nearest star. The bright stars Alpha Centauri A and B form a close binary as they are separated by only 23 times the Earth- Sun distance - slightly greater than the distance between Uranus and the Sun. In the above picture, the brightness of the stars overwhelm the photograph causing an illusion of great size, even though the stars are really just small points of light. The Alpha Centauri system is not visible in much of the northern hemisphere. Alpha Centauri A, also known as Rigil Kentaurus, is the brightest star in the constellation of Centaurus and is the fourth brightest star in the night sky. Sirius is the brightest even thought it is more than twice as far away. By an exciting coincidence, Alpha Centauri A is the same type of star as our Sun, causing many to speculate that it might contain planets that harbor life.
A Triangular Shadow of a Large Volcano (2011-07-05)
Why does the shadow of this volcano look like a triangle? The Mount Teide volcano itself does not have the strictly pyramidal shape that its geometric shadow might suggest.  The triangle shadow phenomena is not unique to the Mt. Teide, though, and is commonly seen from the tops of other large mountains and volcanoes. A key reason for the strange dark shape is that the observer is looking down the long corridor of a sunset (or sunrise) shadow that extends to the horizon. Even if the huge volcano were a perfect cube and the resulting shadow were a long rectangular box, that box would appear to taper off at its top as its shadow extended far into the distance, just as parallel train tracks do. The above spectacular image shows Pico Viejo crater in the foreground, located on Tenerife in the Canary Islands of Spain. The nearly full moon is seen nearby shortly after its total lunar eclipse last month.
Sunrise at Tycho (2011-07-06)
Tycho crater's central peak complex casts a long, dark shadow near local sunrise in this spectacular lunarscape. The dramatic oblique view was recorded on June 10 by the Lunar Reconnaissance Orbiter. Shown in amazing detail, boulder strewn slopes and jagged shadows appear in the highest resolution version at 1.5 meters per pixel. The rugged complex is about 15 kilometers wide, formed in uplift by the giant impact that created the well-known ray crater 100 million years ago. The summit of its central peak reaches 2 kilometers above the Tycho crater floor.
Arp 78: Peculiar Galaxy in Aries (2011-07-07)
Peculiar spiral galaxy Arp 78 is found within the boundaries of the head strong constellation Aries, some 100 million light-years beyond the stars and nebulae of our Milky Way galaxy. Also known as NGC 772, the island universe is over 100 thousand light-years across and sports a single prominent outer spiral arm in this detailed cosmic portrait. Its brightest companion galaxy, compact NGC 770, is toward the upper right of the larger spiral. NGC 770's fuzzy, elliptical appearance contrasts nicely with a spiky foreground Milky Way star in matching yellowish hues. Tracking along sweeping dust lanes and lined with young blue star clusters, Arp 78's large spiral arm is likely due to gravitational tidal interactions. Faint streams of material seem to connect Arp 78 with its nearby companion galaxies.
Saturn Storm Panoramas (2011-07-08)
These tantalizing panoramas follow a remarkable giant storm encircling the northern hemisphere of ringed planet Saturn. Still active, the roiling storm clouds were captured in near-infrared images recorded by the Cassini spacecraft on February 26 and stitched into the high resolution, false-color mosaics. Seen late last year as a prominent bright spot by amateur astronomers when Saturn rose in predawn skies, the powerful storm has grown to enormous proportions. Its north-south extent is nearly 15,000 kilometers and it now stretches completely around the gas giant's northern hemisphere some 300,000 kilometers. Taken about one Saturn day (11 hours) apart, the panoramas show the head of the storm at the left and cover about 150 degrees in longitude. Also a source of radio noise from lightning, the intense storm may be related to seasonal changes as Saturn experiences northern hemisphere spring.  NASA: Space Shuttle Launch Coverage
Atlantis Reflection (2011-07-09)
Space shuttle orbiter Atlantis left planet Earth on Friday, July 8, embarking on the STS-135 mission to the International Space Station. The momentous launch was the final one in NASA's 30 year space shuttle program that began with the launch of the first reusable spacecraft on April 12, 1981. In this reflective prelaunch image from July 7, Atlantis stands in a familiar spot on the Kennedy Space Center's pad 39A, after an early evening roll back of the pad's Rotating Service Structure. The historic orbital voyages of Atlantis have included a Hubble Space Telescope servicing mission, deployment of Magellan, Galileo, and the Compton Gamma-ray Observatory, and seven trips to the Russian space station Mir. Scheduled to dock once again with the International Space Station on Sunday, Atlantis has now made its 33rd and final trip to orbit.
A Milky Way Band (2011-07-10)
Most bright stars in our Milky Way Galaxy reside in a disk.  Since our Sun also resides in this disk, these stars appear to us as a diffuse band that circles the sky.  The above panorama of a northern band of the Milky Way's disk covers 90 degrees and is a digitally created mosaic of several independent exposures.   Scrolling right will display the rest of this spectacular picture. Visible are many bright stars, dark dust lanes, red emission nebulae, blue reflection nebulae, and clusters of stars.  In addition to all this matter that we can see, astronomers suspect there exists even more dark matter that we cannot see.
The Perseus Cluster of Galaxies (2011-07-12)
Here is one of the largest objects that anyone will ever see on the sky. Each of these fuzzy blobs is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies. The cluster is seen through a foreground of faint stars in our own Milky Way Galaxy. Near the cluster center, roughly 250 million light-years away, is the cluster's dominant galaxy NGC 1275, seen above as a large galaxy on the image left. A prodigious source of x-rays and radio emission, NGC 1275 accretes matter as gas and galaxies fall into it. The Perseus Cluster of Galaxies, also cataloged as Abell 426, is part of the Pisces-Perseus supercluster spanning over 15 degrees and containing over 1,000 galaxies. At the distance of NGC 1275, this view covers about 15 million light-years.
Atlantis' Last Approach (2011-07-13)
For the last time, the US Space Shuttle has approached the International Space Station (ISS).  Following a dramatic launch from Cape Canaveral last week that was witnessed by an estimated one million people, Space Shuttle Atlantis on STS-135 lifted a small crew to a welcome rendezvous three days ago with the orbiting station.  Although NASA is discontinuing the aging shuttle fleet, NASA astronauts in the near future will be able to visit the ISS on Russian space flights.  Pictured above, Atlantis rises toward the ISS with its cargo bay doors open, showing a gleaming metallic Raffaello Multi-Purpose Logistics Module.  Over 200 kilometers below lie the cool blue waters of planet Earth. The much-anticipated last glide back to Earth for the Space Shuttle is currently scheduled for next Thursday, July 21.   Quiz: Can you identify what land masses are visible below the shuttle?
Neptune: Once Around (2011-07-14)
Neptune rotates once on its axis in about 16 hours. So, spaced about 4 hours apart these 4 images of the solar system's most distant gas giant cover one Neptune day. Recorded by the Hubble Space Telescope in late June they combine exposures made with visible and near-infrared filters to show high-altitude clouds composed of methane ice crystals against the planet's normally blue cloud tops. Because Neptune's axis of rotation is tilted to its orbital plane by 29 degrees, compared to Earth's 23.5 degrees, Neptune experiences seasons analogous to Earth's. As early summer comes to Neptune's southern hemisphere and winter to the north, Hubble observations have shown cloud activity shifting to the northern hemisphere. In fact the progression of Neptune's seasons has come around once since its position was predicted by French mathematician Urbain Le Verrier and British mathematician John Couch Adams, and the planet was subsequently discovered by German astronomer Johann Galle on September 23, 1846. With an orbital period of approximately 165 years, this week on July 12, Neptune has been once around the Sun since its discovery date.
NGC 3314: When Galaxies Overlap (2011-07-15)
NGC 3314 is actually two large spiral galaxies which just happen to almost exactly line up. The foreground spiral is viewed nearly face-on, its pinwheel shape defined by young bright star clusters. But against the glow of the background galaxy, dark swirling lanes of interstellar dust appear to dominate the face-on spiral's structure. The dust lanes are surprisingly pervasive, and this remarkable pair of overlapping galaxies is one of a small number of systems in which absorption of light from beyond a galaxy's own stars can be used to directly explore its distribution of dust. NGC 3314 is about 140 million light-years (background galaxy) and 117 million light-years (foreground galaxy) away in the multi-headed constellation Hydra. The background galaxy would span nearly 70,000 light-years at its estimated distance. A synthetic third channel was created to construct this dramatic new composite of the overlapping galaxies from two color image data in the Hubble Legacy Archive.
Starry Night over Dubai (2011-07-16)
A starry night over the city of Dubai in the United Arab Emirates is really not so starry. In fact, the Moon is the only celestial beacon to come close to competing with city lights in this night skyscape, a situation all too familiar to urban skygazers. The futuristic looking scene is dominated by the 800 meter tall Khalifa Tower, presently the tallest free standing structure on planet Earth. But for now you should also be able to make out a few of the very brightest stars in Earth's night sky. Capella is left of the tower and Aldebaran, Betelgeuse, Rigel, and stars in Orion's Belt can just be identified in the heavily light-polluted skies. Need some help finding them? Slide your cursor over the image.