omnianasa/nasa-apod-metadata huggingface dataset:
The Longer Days (2019-06-27)
This persistent six month long exposure compresses the time from solstice to solstice (December 21, 2018 to June 16, 2019) into a single point of view. Dubbed a solargraph, the unconventional picture was recorded with a tall, tube-shaped pinhole camera using a piece of photographic paper. Fixed to a single spot at Casarano, Italy for the entire exposure, the simple camera continuously records the Sun's daily path as a glowing trail burned into the photosensitive paper. Breaks and gaps in the trails are caused by cloud cover. At the end of the exposure, the paper was scanned to create the digital image. Of course, starting in December the Sun trails peak lower in the sky, near the northern hemisphere's winter solstice. The trails climb higher as the days grow longer and the June 21st summer solstice approaches.
A Solstice Night in Paris (2019-06-28)
The night of June 21 was the shortest night for planet Earth's northern latitudes, so at latitude 48.9 degrees north, Paris was no exception. Still, the City of Light had an exceptionally luminous evening. Its skies were flooded with silvery night shining or noctilucent clouds after the solstice sunset. Hovering at the edge of space, the icy condensations on meteoric dust or volcanic ash are still in full sunlight at the extreme altitudes of the mesophere. Seen at high latitudes in summer months, stunning, wide spread displays of northern noctilucent clouds are now being reported.
M83: The Thousand-Ruby Galaxy (2019-06-29)
Big, bright, and beautiful, spiral galaxy M83 lies a mere twelve million light-years away, near the southeastern tip of the very long constellation Hydra. Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its popular name, The Southern Pinwheel.  But reddish star forming regions that dot the sweeping arms highlighted in this sparkling color composite also suggest another nickname, The Thousand-Ruby Galaxy. About 40,000 light-years across, M83 is a member of a group of galaxies that includes active galaxy Centaurus A. In fact, the core of M83 itself is bright at x-ray energies, showing a high concentration of neutron stars and black holes left from an intense burst of star formation. This sharp composite color image also features spiky foreground Milky Way stars and distant background galaxies. The image data was taken from the Subaru Telescope, the European Southern Observatory's Wide Field Imager camera, and the Hubble Legacy Archive.
The Big Corona (2019-07-01)
Most photographs don't adequately portray the magnificence of the Sun's corona. Seeing the corona first-hand during a total solar eclipse is unparalleled.  The human eye can adapt to see coronal features and extent that average cameras usually cannot. Welcome, however, to the digital age.  The featured central image digitally combined short and long exposures that were processed to highlight faint and extended features in the corona of the total solar eclipse that occurred in August of 2017.  Clearly visible are intricate layers and glowing caustics of an ever changing mixture of hot gas and magnetic fields in the Sun's corona.  Looping prominences appear bright pink just past the Sun's limb.  Faint details on the night side of the New Moon can even be made out, illuminated by sunlight reflected from the dayside of the Full Earth. Images taken seconds before and after the total eclipse show glimpses of the background Sun known as Baily's Beads and Diamond Ring.  Tomorrow, a new total solar eclipse will be visible from parts of South America.
NGC 1566: The Spanish Dancer Spiral Galaxy (2019-07-02)
If not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe containing billions of stars and situated about 40 million light-years away toward the constellation of the Dolphinfish (Dorado), NGC 1566 presents a gorgeous face-on view. Classified as a grand design spiral, NGC 1566's shows two prominent and graceful spiral arms that are traced by bright blue star clusters and dark cosmic dust lanes. Numerous Hubble Space Telescope images of NGC 1566 have been taken to study star formation, supernovas, and the spiral's unusually active center. Some of these images, stored online in the Hubble Legacy Archive, were freely downloaded, combined, and digitally processed by an industrious amateur to create the featured image. NGC 1566's flaring center makes the spiral one of the closest and brightest Seyfert galaxies, likely housing a central supermassive black hole wreaking havoc on surrounding stars and gas.   Today: Total solar eclipse visible in parts of South America
In the Shadow of the Moon (2019-07-04)
On July 2 denizens of planet Earth could stand in the Moon's dark umbral shadow during South America's 2019 total solar eclipse. It first touched down in the Southern Pacific Ocean, east of New Zealand. Racing toward the east along a narrow track, the shadow of the Moon made landfall along the Chilean coast with the Sun low on the western horizon. Captured in the foreground here are long shadows still cast by direct sunlight though, in the final moments before totality began. While diffraction spikes are from the camera lens aperture, the almost totally eclipsed Sun briefly shone like a beautiful diamond ring in the clear, darkened sky.
La Silla Eclipse Sequence (2019-07-05)
The road to the high mountaintop La Silla Observatory in the Chilean Atacama Desert also led in to the path of July 2nd's total solar eclipse. Recorded at regular intervals before and after the total eclipse phase, the frames in this composite sequence include the moment the Moon's dark shadow fell across some of planet Earth's advanced large telescopes. The dreamlike view looks west toward the setting Sun and the approaching Moon shadow. In fact La Silla was a little north of the shadow track's center line, so the region's stunning, clear skies are slightly brighter to the north (right) in the scene.
8 Minute and 30 Second Eclipse (2019-07-06)
The total phase of the July 2nd solar eclipse lasted about 4 minutes and 30 seconds at the point of maximum eclipse. On the surface of planet Earth, that was about 600 nautical miles north of Easter Island in the Southern Pacific Ocean. But from 41,000 feet above, on a charter flight intercepting the Moon's shadow, the Moon could be seen to completely block the Sun for about 8 minutes and 30 seconds. With a tailwind at the mid-eclipse intercept point, the plane was traveling around 488 nautical miles per hour chasing along the Moon's shadow track. From above the clouds this wide-field image of the totally eclipsed Sun and shimmering solar corona over the wing records the spectacular view from a window seat on the sunward side of the aircraft.
Crescent Saturn (2019-07-07)
Saturn never shows a crescent phase -- from Earth.  But when viewed from beyond, the majestic giant planet can show an unfamiliar diminutive sliver. This image of crescent Saturn in natural color was taken by the robotic Cassini spacecraft in 2007. The featured image captures Saturn's majestic rings from the side of the ring plane opposite the Sun -- the unilluminated side -- another vista not visible from Earth. Pictured are many of Saturn's photogenic wonders, including the subtle colors of cloud bands, the complex shadows of the rings on the planet, and the shadow of the planet on the rings. A careful eye will find the moons Mimas (2 o'clock) and Janus (4 o'clock), but the real challenge is to find Pandora (8 o'clock).  Saturn is now nearly opposite from the Sun in the Earth's sky and so can be seen in the evening starting just after sunset for the rest of the night.
The Galactic Center in Radio from MeerKAT (2019-07-08)
What's happening at the center of our galaxy? It's hard to tell with optical telescopes since visible light is blocked by intervening interstellar dust. In other bands of light, though, such as radio, the galactic center can be imaged and shows itself to be quite an interesting and active place.  The featured picture shows the inaugural image of the MeerKAT array of 64 radio dishes just completed in South Africa. Spanning four times the angular size of the Moon (2 degrees), the image is impressively vast, deep, and detailed.  Many known sources are shown in clear detail, including many with a prefix of Sgr, since the Galactic Center is in the direction of the constellation Sagittarius.  In our Galaxy's Center lies Sgr A, found here just to the right of the image center, which houses the Milky Way's central supermassive black hole.  Other sources in the image are not as well understood, including the Arc, just to the left of  Sgr A, and numerous filamentary threads. Goals for MeerKAT include searching for radio emission from neutral hydrogen emitted in a much younger universe and brief but distant radio flashes.
Birds During a Total Solar Eclipse (2019-07-09)
What do birds do during a total solar eclipse? Darkness descends more quickly in a total eclipse than during sunset, but returns just as quickly -- and perhaps unexpectedly  to the avians -- just a few minutes later. Stories about the unusual behavior of birds during eclipses have been told for centuries, but bird reactions were recorded and studied systematically by citizen scientists participating in an eBird project during the total solar eclipse that crossed the USA in 2017 August.  Although some unusual behaviors were observed, many observers noted birds acting like it was dusk and either landing or flying low to the ground.  Radar confirmed a significant decrease in high-flying birds and insects during and just after totality.  Conversely, several sightings of normally nocturnal birds were reported.  Pictured, a flock of birds in La Serena, Chile flew through the air together during the total solar eclipse that crossed South America last week. The photographer captured the scene in frames from an eclipse video.  The next total solar eclipse in 2020 December will also cross South America, while in 2024 April a total solar eclipse will cross North America from Mexico through New England, USA.   Gallery 2019: Notable total eclipse images submitted to APOD
The Ghost of Jupiter's Halo (2019-07-11)
Close-up images of NGC 3242 show the cast off shroud of a dying, sun-like star fancifully known as The Ghost of Jupiter nebula. But this deep and wide telescopic view also finds the seldom seen outer halo of the beautiful planetary nebula at the upper left, toward Milky Way stars and background galaxies in the serpentine constellation Hydra. Intense and otherwise invisible ultraviolet radiation from the nebula's central white dwarf star powers its illusive glow in visible light. In fact, planets of NGC 3242's evolved white dwarf star may have contributed to the nebula's symmetric features and shape. Activity beginning in the star's red giant phase, long before it produced a planetary nebula, is likely the cause of the fainter more extensive halo. About a light-year across NGC 3242 is some 4,500 light-years away. The tenuous clouds of glowing material at the right could well be interstellar gas, by chance close enough to the NGC 3242's white dwarf to be energized by its ultraviolet radiation.
Magellanic Galaxy NGC 55 (2019-07-12)
Irregular galaxy NGC 55 is thought to be similar to the Large Magellanic Cloud (LMC). But while the LMC is about 180,000 light-years away and a well-known satellite of our own Milky Way Galaxy, NGC 55 is more like 6 million light-years distant, a member of the Sculptor Galaxy Group. Classified as an irregular galaxy, in deep exposures the LMC itself resembles a barred disk galaxy. Spanning about 50,000 light-years, NGC 55 is seen nearly edge-on though, presenting a flattened, narrow profile in contrast with our face-on view of the LMC. Just as large star forming regions create emission nebulae in the LMC, NGC 55 is also seen to be producing new stars. This highly detailed galaxy portrait highlights a bright core crossed with dust clouds, telltale pinkish star forming regions, and young blue star clusters in NGC 55.
The Eagle Rises (2019-07-13)
Get out your red/blue glasses and check out this stereo view from lunar orbit. The 3D anaglyph was created from two photographs (AS11-44-6633, AS11-44-6634) taken by astronaut Michael Collins during the 1969 Apollo 11 mission. It features the lunar module ascent stage, dubbed The Eagle, rising to meet the command module in lunar orbit on July 21. Aboard the ascent stage are Neil Armstrong and Buzz Aldrin, the first to walk on the Moon. The smooth, dark area on the lunar surface is Mare Smythii located just below the equator on the extreme eastern edge of the Moon's near side.  Poised beyond the lunar horizon is our fair planet Earth.
Eagle Aurora over Norway (2019-07-14)
What's that in the sky? An aurora. A large coronal mass ejection occurred on our Sun five days before this 2012 image was taken, throwing a cloud of fast moving electrons, protons, and ions toward the Earth. Although most of this cloud passed above the Earth, some of it impacted our Earth's magnetosphere and resulted in spectacular auroras being seen at high northern latitudes. Featured here is a particularly photogenic auroral corona captured above Grotfjord, Norway. To some, this shimmering green glow of recombining atmospheric oxygen might appear as a large eagle, but feel free to share what it looks like to you.  Although the Sun is near Solar Minimum, streams of the solar wind continue to impact the Earth and create impressive auroras visible even last week.
The Space Station Crosses a Spotless Sun (2019-07-15)
That's no sunspot. It's the International Space Station (ISS) caught passing in front of the Sun. Sunspots, individually, have a dark central umbra, a lighter surrounding penumbra, and no solar panels.  By contrast, the ISS is a complex and multi-spired mechanism, one of the largest and most sophisticated machines ever created by humanity.  Also, sunspots occur on the Sun, whereas the ISS orbits the Earth.  Transiting the Sun is not very unusual for the ISS, which orbits the Earth about every 90 minutes, but getting one's timing and equipment just right for a great image is rare.  Strangely, besides that fake spot, in this recent two-image composite, the Sun  lacked any real sunspots.  The featured picture combines two images -- one capturing the space station transiting the Sun -- and another taken consecutively capturing details of the Sun's surface.  Sunspots have been rare on the Sun since the dawn of the current Solar Minimum, a period of low solar activity. For reasons not yet fully understood, the number of sunspots occurring during both the previous and current solar minima have been unusually low.
Shadowed Moon and Mountain (2019-07-18)
On July 16 the Moon celebrated the 50th anniversary of the launch of Apollo 11 with a lunar eclipse visible from much of planet Earth. In this view part of the lunar disk is immersed in Earth's dark, reddened umbral shadow. Near the maximum eclipse phase, it just touches down along a mountain ridge. The rugged Tyrolean nightscape was recorded after moonrise south of Innsbruck, Austria with a dramatically lit communication tower along the ridgeline. Of course eclipses rarely travel alone. This partial lunar eclipse was at the Full Moon following July 2nd's New Moon and total eclipse of the Sun.
Tranquility Base Panorama (2019-07-19)
On July 20, 1969 the Apollo 11 lunar module Eagle safely touched down on the Moon. It landed near the southwestern corner of the Moon's Mare Tranquillitatis at a landing site dubbed Tranquility Base. This panoramic view of Tranquility Base was constructed from the historic photos taken from the lunar surface. On the far left astronaut Neil Armstrong casts a long shadow with Sun is at his back and the Eagle resting about 60 meters away ( AS11-40-5961). He stands near the rim of 30 meter-diameter Little West crater seen here to the right ( AS11-40-5954). Also visible in the foreground is the top of the camera intended for taking stereo close-ups of the lunar surface.
Apollo 11 Landing Panorama (2019-07-20)
Have you seen a panorama from another world lately? Assembled from high-resolution scans of the original film frames, this one sweeps across the magnificent desolation of the Apollo 11 landing site on the Moon's Sea of Tranquility. The images were taken by Neil Armstrong looking out his window of the Eagle Lunar Module fifty years ago, shortly after the July 20, 1969 landing. The frame at the far left (AS11-37-5449) is the first picture taken by a person on another world. Toward the south, thruster nozzles can be seen in the foreground on the left, while at the right, the shadow of the Eagle is visible to the west. For scale, the large, shallow crater on the right has a diameter of about 12 meters. Frames taken from the Lunar Module windows about an hour and a half after landing, before walking on the lunar surface, were intended to initially document the landing site in case an early departure was necessary.
Moonquakes Surprisingly Common (2019-07-21)
Why are there so many moonquakes?   Analyses of seismometers left on the moon by the Apollo moon landings reveals a surprising number of moonquakes occurring within 100 kilometers of the surface.   In fact, 62 moonquakes were detected in data recorded between 1972 and 1977.   Many of these moonquakes are not only strong enough to move furniture in a lunar apartment, but the stiff rock of the moon continues to vibrate for many minutes, significantly longer than the softer rock earthquakes on Earth.   The cause of the moonquakes remains unknown, but a leading hypothesis is the collapse of underground faults. Regardless of the source, future moon dwellings need to be built to withstand the frequent shakings.   Pictured here 50 years ago today, Apollo 11 astronaut Buzz Aldrin stands beside a recently deployed lunar seismometer, looking back toward the lunar landing module.
HDR: Earth's Circular Shadow on the Moon (2019-07-22)
What could create such a large circular shadow on the Moon? The Earth. Last week's full Moon -- the Buck Moon -- was so full that it fell almost exactly in a line with the Sun and the Earth.  When that happens the Earth casts its shadow onto the Moon. The circularity of the Earth's shadow on the Moon was commented on by Aristotle and so has been noticed since at least the 4th century BC.  What's new is humanity's ability to record this shadow with such high dynamic range (HDR).  The featured HDR composite of last week's partial lunar eclipse combines 15 images and include an exposure as short as 1/400th of a second -- so as not to overexpose the brightest part -- and an exposure that lasted five seconds -- to bring up the dimmest part. This dimmest part -- inside Earth's umbra -- is not completely dark because some light is refracted through the Earth's atmosphere onto the Moon.  A total lunar eclipse will occur next in 2021 May.   Partial Lunar Eclipse in 2019 July: Some memorable images submitted to APOD
M82: Galaxy with a Supergalactic Wind (2019-07-23)
Why is the Cigar Galaxy billowing red smoke?  M82, as this starburst galaxy is also known, was stirred up by a recent pass near large spiral galaxy M81.  This doesn't fully explain the source of the red-glowing outwardly expanding gas and dust, however.  Evidence indicates that this gas and dust is being driven out by the combined emerging particle winds of many stars, together creating a galactic superwind.  The dust particles are thought to originate in M82's interstellar medium and are actually similar in size to particles in cigar smoke.  The featured photographic mosaic highlights a specific color of red light strongly emitted by ionized hydrogen gas, showing detailed filaments of this gas and dust.  The filaments extend for over 10,000 light years. The 12-million light-year distant Cigar Galaxy is the brightest galaxy in the sky in infrared light, and can be seen in visible light with a small telescope towards the constellation of the Great Bear (Ursa Major).   APOD in other languages: Arabic, Catalan, Chinese (Beijing), Chinese (Taiwan), Croatian, Czech, Dutch, Farsi, French, French, German, Hebrew, Indonesian, Japanese, Korean, Montenegrin, Polish, Russian, Serbian, Slovenian,  Spanish and Ukrainian
Zodiacal Road (2019-07-24)
What's that strange light down the road? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset -- or just before sunrise -- and is called zodiacal light.  Although the origin of this dust is still being researched, a leading hypothesis holds that zodiacal dust originates mostly from faint Jupiter-family comets and slowly spirals into the Sun. Recent analysis of dust emitted by Comet 67P, visited by ESA's robotic Rosetta spacecraft, bolster this hypothesis.  Pictured when climbing a road up to Teide National Park in the Canary Islands of Spain, a bright triangle of zodiacal light appeared in the distance soon after sunset. Captured on June 21, the scene includes bright Regulus, alpha star of Leo, standing above center toward the left. The Beehive Star Cluster (M44) can be spotted below center, closer to the horizon and also immersed in the zodiacal glow.
Cygnus Skyscape (2019-07-25)
In brush strokes of interstellar dust and glowing hydrogen gas, this beautiful skyscape is painted across the plane of our Milky Way Galaxy near the northern end of the Great Rift and the constellation Cygnus the Swan. Composed with three different telescopes and about 90 hours of image data the widefield mosaic spans an impressive 24 degrees across the sky. Alpha star of Cygnus, bright, hot, supergiant Deneb lies near top center. Crowded with stars and luminous gas clouds Cygnus is also home to the dark, obscuring Northern Coal Sack Nebula, extending from Deneb toward the center of the view. The reddish glow of star forming regions NGC 7000, the North America Nebula and IC 5070, the Pelican Nebula, are just left of Deneb. The Veil Nebula is a standout below and left of center. A supernova remnant, the Veil is some 1,400 light years away, but many other nebulae and star clusters are identifiable throughout the cosmic scene. Of course, Deneb itself is also known to northern hemisphere skygazers for its place in two asterisms -- marking the top of the Northern Cross and a vertex of the Summer Triangle.
The Veins of Heaven (2019-07-26)
Transfusing sunlight through a still dark sky, this exceptional display of noctilucent clouds was captured earlier this month, reflected in the calm waters of Vallentuna Lake near Stockholm, Sweden. From the edge of space, about 80 kilometers above Earth's surface, the icy clouds themselves still reflect sunlight even though the Sun is below the horizon as seen from the ground. Usually spotted at high latitudes in summer months the night shining clouds have made a strong showing so far during the short northern summer nights. Also known as polar mesopheric clouds they are understood to form as water vapor driven into the cold upper atmosphere condenses on the fine dust particles supplied by disintegrating meteors or volcanic ash. NASA's AIM mission provides daily projections of noctilucent clouds as seen from space.
Chandrayaan 2 Launch (2019-07-27)
On July 22nd this GSLV (Geosynchronous Satellite Launch Vehicle) MkIII rocket vanished from sight into a cloud bank an instant after this dramatic snapshot was taken. Launched from India's Satish Dhawan Space Centre it carried the Chandrayaan 2 mission spacecraft into Earth orbit. The spacecraft's orbiter, lander, and rover are destined for the Moon, though. In the coming weeks it will perform a series of orbit raising maneuvers, eventually transferring to lunar orbit in early September. Carrying the solar-powered rover, the lander is scheduled to separate and attempt its autonomous soft landing at high latitudes near the lunar south pole. It should arrive on the lunar nearside near local sunrise and the start of about two Earth weeks of lunar daylight on September 7.