omnianasa/nasa-apod-metadata huggingface dataset:
Galactic Collision in Cluster Abell 1185 (2005-11-22)
What is a guitar doing in a cluster of galaxies? Colliding.  Clusters of galaxies are sometimes packed so tight that the galaxies that compose them collide.  A prominent example occurs on the left of the above image of the rich cluster of galaxies Abell 1185.   There at least two galaxies, cataloged as Arp 105 and dubbed The Guitar for their familiar appearance, are pulling each other apart gravitationally.  Most of Abell 1185's hundreds of galaxies are elliptical galaxies, although spiral, lenticular, and irregular galaxies are all clearly evident.  Many of the spots on the above image are fully galaxies themselves containing billions of stars, but some spots are foreground stars in our own Milky Way Galaxy.  Recent observations of Abell 1185 have found unusual globular clusters of stars that appear to belong only to the galaxy cluster and not to any individual galaxy. Abell 1185 spans about one million light years and lies 400 million light years distant.
Pandora: A Shepherd Moon of Saturn (2005-11-23)
What does Saturn's small moon Pandora look like?  To help find out, the robot Cassini spacecraft now orbiting Saturn passed about 50,000 kilometers from the unusual moon in early September.  The highest resolution image of Pandora ever taken was then captured and is shown above in representative colors.  Features as small as 300 meters can be discerned on 80-kilometer wide Pandora.  Craters on Pandora appear to be covered over by some sort of material, providing a more smooth appearance than sponge-like Hyperion, another small moon of Saturn.  Curious grooves and ridges also appear to cross the surface of the small moon.  Pandora is partly interesting because, along with its companion moon Prometheus, it helps shepherd the particles of Saturn's F ring into a distinct ring.
Dusty NGC 1333 (2005-11-24)
Dusty NGC 1333 is seen as a reflection nebula in visible light images, sporting bluish hues characteristic of starlight reflected by dust. But at longer infrared wavelengths, the interstellar dust itself glows - shown in red in this false-color Spitzer Space Telescope image. The penetrating infrared view also shows youthful stars that would otherwise still be obscured by the dusty clouds which formed them. Notably, greenish streaks and splotches that seem to litter the region trace the glow of cosmic jets blasting away from emerging young stellar objects as the jets plow into the cold cloud material. In all, the chaotic scene likely resembles one in which our own Sun formed over 4.5 billion years ago. NGC 1333 is a mere 1,000 light-years distant in the constellation Perseus.
Moon Over Antarctica (2005-11-25)
Last week, the nearly Full Moon set along the northern horizon - as seen from Davis Station, Antarctica.  The squashed orange pumpkin shape just silhouettes the peak of a distant iceberg in this stunning view.  The Moon's apparently squashed shape is due to atmospheric bending of light or refraction - an effect which is more severe closer to the horizon. Skimming low along the stark features of the frozen landscape, the Moon's lower edge appears noticeably more distorted than the upper limb. Along with about 70 others present at Davis Station, Dr. Jim Behrens had a chance to enjoy the view while studying the ongoing detachment of a large iceberg known as "Loose Tooth".
A Stereo Sun (2005-11-26)
A stereo view of the closest star, this creatively composited image was constructed from an extensive archive of pictures taken between March 2004 and April 2005. When viewed with red/blue glasses, the Sun's disk and surface features, including sunspots, filaments, and prominences, stand out in an exaggerated stereo perspective. The images were recorded through a narrow band hydrogen-alpha filter, designed to transmit only light from hydrogen atoms in the solar atmosphere. After combining the solar hydrogen-alpha images, a 3D star field was added to the final anaglyphic stereo view.
Light Echoes from V838 Mon (2005-11-27)
What caused this outburst of V838 Mon?  For reasons unknown, star V838 Mon's outer surface suddenly greatly expanded with the result that it became the brightest star in the entire Milky Way Galaxy in January 2002.  Then, just as suddenly, it faded.  A stellar flash like this has never been seen before -- supernovas and novas expel matter out into space.  Although the V838 Mon flash appears to expel material into space, what is seen in the above image from the Hubble Space Telescope is actually an outwardly moving light echo of the bright flash.  In a light echo, light from the flash is reflected by successively more distant rings in the complex array of ambient interstellar dust that already surrounded the star.  V838 Mon lies about 20,000 light years away toward the constellation of the unicorn (Monoceros), while the light echo above spans about six light years in diameter.
Vista Inside Gusev Crater on Mars (2005-11-28)
What is the geologic history of Mars?  To help find out, the robot Spirit rover explored the terrain on the way up to the top of Husband Hill and took pictures along the way.  Earth-bound team members later combined images from one camera with colors from another to create this semi-realistic vista from near the top of the rugged hill.   Many rock faces were imaged and probed along the way.  The above image captures not only a high and distant Mars inside Gusev crater, but also more of the refrigerator-sized Spirit rover than other similar vistas.  Visible technology includes a wide array of energy-absorbing solar panels, a sundial, and the circular high gain communications antenna.
Simeis 147: Supernova Remnant from Palomar (2005-11-29)
It's easy to get lost following the intricate filaments in this detailed image of faint supernova remnant Simeis 147. Seen towards the constellation Taurus it covers nearly 3 degrees (6 full moons) on the sky corresponding to a width of 150 light-years at the stellar debris cloud's estimated distance of 3,000 light-years. The above image is a color composite of 66 blue and red color band images from the National Geographic Palomar Observatory Sky Survey taken with the wide field Samuel Oschin 48-inch Telescope.  The area of the sky shown covers over 70 times the area of the full Moon. This supernova remnant has an apparent age of about 100,000 years - meaning light from the massive stellar explosion first reached Earth 100,000 years ago - but this expanding remnant is not the only aftermath. The cosmic catastrophe also left behind a spinning neutron star or pulsar, all that remains of the original star's core.
Reflections on the Horsehead Nebula (2005-11-30)
Sculpted by stellar winds and radiation, a magnificent interstellar dust cloud by chance has assumed this recognizable shape.  Fittingly named the Horsehead Nebula, it is some 1,500 light-years distant, embedded in the vast Orion cloud complex. About five light-years "tall", the dark cloud is cataloged as Barnard 33 and is visible only because its obscuring dust is silhouetted against the glowing red emission nebula IC 434.  Contrasting blue reflection nebula NGC 2023 is visible on the lower left.  In this gorgeous color image, both Horsehead and NGC 2023 seem to be caught in beams of light shining from above -- but the beams are actually just internal reflections from bright star Sigma Orionis, just off the upper edge of the view.
SOHO's Uninterrupted View of the Sun (2005-12-01)
Launched ten years ago this week, SOHO (the SOlar and Heliospheric Observatory) still enjoys an uninterrupted view of the Sun. Twelve sungazing instruments on board the spacecraft have explored the Sun's internal structure, the extensive solar atmosphere and solar wind, and discovered over 1,000 comets from a remarkable orbit around a point about 1.5 million kilometers directly sunward of planet Earth itself. At that location, known as a Lagrange point, the gravitational influence of the Earth and Sun are equal. With scientific instrument teams distributed around the world, the SOHO operations center is located at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Mission operations are planned through March of 2007 to allow the study of a complete 11-year solar cycle. Contributions from SOHO's instruments are represented in the colorful montage image. Happy tenth anniversary SOHO!
Crab Nebula Mosaic from HST (2005-12-02)
The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous list of things which are not comets. In fact, the cosmic Crab is now known to be a supernova remnant, an expanding cloud of debris from the death explosion of a massive star. Light from that stellar catastrophe was first witnessed by astronomers on planet Earth in the year 1054. Composed of 24 exposures taken in October 1999, January 2000, and December 2000, this Hubble Space Telescope mosaic spans about twelve light years. Colors in the intricate filaments trace the light emitted from atoms of hydrogen, oxygen, and sulfur in the debris cloud. The spooky blue interior glow is emitted by high-energy electrons accelerated by the Crab's central pulsar. One of the most exotic objects known to modern astronomers, the pulsar is a neutron star, the spinning remnant of the collapsed stellar core. The Crab Nebula lies about 6,500 light-years away in the constellation Taurus.
Astro 1 In Orbit (2005-12-03)
Fifteen years ago, in December of 1990, the Space Shuttle Orbiter Columbia carried an array of astronomical telescopes high above the Earth's obscuring atmosphere to explore the Universe at ultraviolet and x-ray wavelengths. The telescopes, known by the acronyms UIT, HUT, WUPPE, and BBXRT, are seen here in Columbia's payload bay against a spectacular view of the constellation Orion. The ultraviolet telescopes were mounted on a common structure - HUT is visible in this view along with a star tracker (the silver cone at the left). Taken during the nighttime portion of the shuttle's 90 minute orbit, the picture shows the telescopes and structures illuminated by moonlight.
Proxima Centauri: The Closest Star (2005-12-04)
What is the closest star to our Sun?  It is Proxima Centauri, the nearest member of the Alpha Centauri triple star system.  Light takes only 4.22 years to reach us from Proxima Centauri.  This small red star, captured in the center of the above image,  is so faint that it was only discovered in 1915 and is only visible through a telescope.  Stars of all types from our Milky Way Galaxy are visible in the background.  The brightest star in the Alpha Centauri system is quite similar to our Sun, has been known as long as recorded history, and is the third brightest star in the night sky.  The Alpha Centauri system is primarily visible from Earth's Southern Hemisphere.
Fountains Discovered on Saturn's Enceladus (2005-12-05)
Fountains of ice shoot out from Saturn's moon Enceladus.  Clear discovery images of the fountains were made using observations from the robot Cassini spacecraft currently orbiting Saturn.  During a recent pass, Cassini was programmed to look back toward the Sun where Enceladus would appear as a thin crescent.  From this vantage point, particles emitted from the surface would better show themselves by reflecting sunlight.  The tactic was successful -- the above frame shows several plumes emanating from regions previously known to contain gashes in the surface dubbed tiger stripes.  Cassini detected an increase in particle emissions from these regions during a July flyby.  Some of these ice particles likely contribute to the make up of Saturn's mysterious E ring.
The Veil Nebula Unveiled (2005-12-06)
These wisps of gas are all that remain visible of a Milky Way star.  Many thousands of years ago that star exploded in a supernova leaving the Veil Nebula, pictured above.  At the time, the expanding cloud was likely as bright as a crescent Moon toward the constellation of Cygnus, visible for weeks to people living at the dawn of recorded history.  The supernova remnant lies about 1400 light-years away and covers over five times the size of the full Moon.  The above image of the Veil was made clearer by digitally dimming stars in the frame. The bright wisp at the top is known as the Witch's Broom Nebula and can be seen with a small telescope.  The Veil Nebula is also known as the Cygnus Loop.
Europe at Night (2005-12-07)
Can you find your favorite European city?  The above digital fantasy of Europe at Night is a digital composite of archived satellite images taken both during the day and night.  This image is different from what an astronaut would see for reasons including a complete lack of clouds and an unrealistic exaggeration of lights and contrasts.  Even so, the geography underlying the image is captivating.   Nighttime light patterns have been accumulated from the USAF Defense Meteorological Satellite Program (DMSP) Operational Linescan System.
X-Rays from the Perseus Cluster Core (2005-12-08)
The Perseus Cluster of thousands of galaxies, 250 million light-years distant, is one of the most massive objects in the Universe and the brightest galaxy cluster in the x-ray sky. At its core lies the giant cannibal galaxy Perseus A (NGC 1275), accreting matter as gas and galaxies fall into it. This deep Chandra Observatory x-ray image spans about 300,000 light-years across the galaxy cluster core. It shows remarkable details of x-ray emission from the monster galaxy and surrounding hot (30-70 million degrees C) cluster gas.  The bright central source is the supermassive black hole at the core of Perseus A itself. Low density regions are seen as dark bubbles or voids, believed to be generated by cyclic outbursts of activity from the central black hole. The activity creates pressure waves - sound waves on a cosmic scale- that ripple through the x-ray hot gas. Dramatically, the blue-green wisps just above centre in the false-color view are likely x-ray shadows of the remains of a small galaxy falling into the burgeoning Perseus A.
December Moon Meets Evening Star (2005-12-09)
If you've been outdoors near sunset, then you've probably noticed Venus low in the west as the brilliant evening star. Sometimes mistaken for a tower light near the horizon, Venus is the third brightest celestial beacon, after the Sun and Moon, in planet Earth's sky. That distinction is particularly easy to appreciate in this peaceful scene featuring the crescent Moon, Venus, and sunset colors captured on December 4th near Albany, Missouri, USA. As this season's evening star, Venus will be at its most brilliant tonight, but as December progresses the bright planet will begin to fall out of the western sky. By early next week, December's Moon will have moved on to meet another bright planet overhead -- Mars.
The Last Moon Shot (2005-12-10)
In 1865 Jules Verne predicted the invention of a space capsule that could carry people. His science fiction story "From the Earth to the Moon" outlined his vision of a cannon in Florida so powerful that it could shoot a Projectile-Vehicle carrying three adventurers to the Moon. Over 100 years later NASA, guided by  Wernher Von Braun's vision, produced the Saturn V rocket. From a spaceport in Florida, this rocket turned Verne's fiction into fact, launching 9 Apollo Lunar missions and allowing 12 astronauts to walk on the Moon. As spotlights play on the rocket and launch pad at dusk, the last moon shot, Apollo 17, is pictured here awaiting its December 1972 night launch.
R136: The Massive Stars of 30 Doradus (2005-12-11)
In the center of star-forming region 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known.  These stars, known as the star cluster R136, and part of the surrounding nebula are captured here in this gorgeous visible-light image from the Hubble Space Telescope.  Gas and dust clouds in 30 Doradus, also known as the Tarantula Nebula, have been sculpted into elongated shapes by powerful winds and ultraviolet radiation from these hot cluster stars.  The 30 Doradus Nebula lies within a neighboring galaxy, the Large Magellanic Cloud, located a mere 170,000 light-years away.
30 Doradus: The Tarantula Zone (2005-12-12)
The Tarantula Nebula is more than 1,000 light-years across - a giant emission nebula within our neighboring galaxy the Large Magellanic Cloud. Inside this cosmic arachnid lies a central young cluster of massive stars, cataloged as R136, whose intense radiation and strong winds have helped energize the nebular glow and shape the spidery filaments. In this impressive color mosaic of images from the Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory (CTIO) in Chile, other young star clusters can be seen still within the nebula's grasp. Also notable among the denizens of the Tarantula zone are several dark clouds, sprawling wispy filaments of gas, compact emission nebula, nearly spherical supernova remnants, and areas surrounding hot stars known as superbubbles. The rich mosaic's field of view covers an area on the sky about the size of the full moon in the southern constellation Dorado.
620 Kilometers Above Rhea (2005-12-13)
What does the surface of Saturn's moon Rhea look like?  To help find out, the robot Cassini spacecraft currently orbiting Saturn was directed to fly right past the second largest moon of the gas giant planet late last month.  Pictured above is an image taken only 620 kilometers above Rhea's icy surface, spanning about 90 kilometers. The rim of an old crater crosses the middle of the image, with many smaller and younger craters scattered throughout.  A linear depression -- possibly a tectonic fault -- is visible toward the right, crossing the likely loose material that composes Rhea's surface regolith.   The origins of many features on Rhea are currently unexplained and being researched.
A Digital Opportunity Rover on Mars (2005-12-14)
If you could see one of the robot rovers currently rolling across Mars, what would it look like?  To gain this perspective useful in planning explorations, the above synthetic image was produced digitally.  Above, a digital model of the Opportunity rover was added to a real image of the inside of Endurance Crater on Mars taken earlier by Opportunity itself.  The size of the six-wheeled robot was scaled to the size of the tracks that the Opportunity rover actually created.  In actuality, both the Opportunity and Spirit rovers currently rolling across Mars each span about two meters and so are similar in size to a large rolling desk.  Also visible in the image is dark soil, ancient light rock and numerous small gray pellets known as blueberries.
Autumn Moon Encore (2005-12-15)
Near its northernmost declination, tonight's Full Moon will be a special one, arcing high in northern hemisphere skies. But a Full Moon won't occur on this calendar date for another 19 years, a period known as the lunar Metonic cycle. September 15th's lunar phase and date were notable too, marking the return of a gibbous Moon rising over the High Sierra mountains. That scene was captured in Ansel Adams' famous photograph Autumn Moon from Glacier Point, Yosemite National Park. Earlier this year, Texas State University physicists Donald Olson, Russell Doescher and students were able to pinpoint the location and (formerly uncertain) date the original Ansel Adams photo was taken - September 15, 1948. Accordingly, their astronomical detective work predicted that the lunar alignment and waxing gibbous phase would be repeated on Thursday, September 15, 2005, exactly three 19-year Metonic cycles later. On that day, about 300 photographers gathered at Glacier Point to record Ansel Adams' Autumn Moon encore.
GLIMPSE the Milky Way (2005-12-16)
Scroll right and gaze through the dusty plane of our Milky Way Galaxy in infrared light. The cosmic panorama is courtesy of the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) project and the Spitzer Space Telescope. The galactic plane itself runs through the middle of the false-color view that spans nine degrees (about 18 full moons) across the southern constellation Norma. Spitzer's infrared cameras see through much of the galaxy's obscuring dust revealing many new star clusters as well as star forming regions (bright white splotches) and hot interstellar hydrogen gas (greenish wisps). The pervasive red clouds are emission from dust and organic molecules, pocked with holes and bubbles blown by energetic outflows from massive stars. Intensely dark patches are regions of dust too dense for even Spitzer's infrared vision to penetrate.
Apollo 17: Last on the Moon (2005-12-17)
In December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon, in the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead. Near the beginning of their third and final excursion across the lunar surface, Schmitt took this picture of Cernan flanked by an American flag and their lunar rover's umbrella-shaped high-gain antenna. The prominent Sculptured Hills lie in the background while Schmitt's reflection can just be made out in Cernan's helmet. The Apollo 17 crew returned with 110 kilograms of rock and soil samples, more than from any of the other lunar landing sites. Cernan and Schmitt are still the last to walk on the Moon.
M83: The Southern Pinwheel Galaxy from VLT (2005-12-18)
M83 is one of the closest and brightest spiral galaxies on the sky. Visible with binoculars in the constellation of Hydra, majestic spiral arms have prompted its nickname as the Southern Pinwheel. Although discovered 250 years ago, only much later was it appreciated that M83 was not a nearby gas cloud, but a barred spiral galaxy much like our own Milky Way Galaxy.  M83, pictured above in a photograph from a Very Large Telescope, is a prominent member of a group of galaxies that includes Centaurus A and NGC 5253, all of which lie about 15 million light years distant.  Several bright supernova explosions have been recorded in M83.  An intriguing double circumnuclear ring has been discovered at the center of M83.
Thin Rings Around Polarized Saturn (2005-12-19)
How thin are the rings of Saturn?  Brightness measurements from different angles have shown Saturn's rings to be about one kilometer thick, making them many times thinner, in relative proportion, than a razor blade.  This thinness sometimes appears in dramatic fashion during an image taken nearly along the ring plane.  The robot Cassini spacecraft now orbiting Saturn has now captured another shot that dramatically highlights the ring's thinness.  The above artistic looking image was taken early last month in infrared polarized light.   If alone in space, the unlit part of Saturn would be much darker.  Reflection of light off of moons like Enceladus (pictured) and the billions of small particles in Saturn's rings, however, gives the giant space orb an unusual glow, an effect highlighted in polarized light.
Star Trails Above Mauna Kea (2005-12-20)
Is there a road to the stars?  Possibly there are many, but the physical road pictured above leads up to the top of a dormant volcano that is a premier spot on planet Earth for observing stars and astronomical phenomena.  At the top of Hawaii's Mauna Kea are some of the largest optical telescopes on Earth, including the Keck telescopes, Gemini, Subaru, CFHT, and the IRTF.  Together, these 10-meter eyes have made many universe-redefining discoveries, including detailing that most of the universe is made not of familiar matter but of mysterious dark matter and dark energy.  The above picture was compiled from over 150 one-minute exposures from a digital camera.  During that time, the rotation of the Earth made the stars far in the distance appear to have long star trails.  The foreground landscape was illuminated by the Moon.