omnianasa/nasa-apod-metadata huggingface dataset:
The Sun Erupts (1996-09-16)
The Sun is a seething ball of extremely hot gas. Above, the Sun was captured by Skylab in 1973 throwing off one the largest eruptive prominences in recorded history. The Sun has survived for about 5 billion years, and will likely survive for another 5 billion. The Sun is not on fire, will never explode, and a solar flare will never destroy the Earth. The Sun continues to present many unanswered questions. For example: Why is the Sun's corona so hot? What causes the Sun's unusual magnetic field? Why does the Sun's center emit so few neutrinos?
Comet Hale-Bopp Fades (1996-09-17)
 Comet Hale-Bopp has faded in the past few weeks. For Hale-Bopp, promised as the Great Comet of 1997, this was a bit of a disappointment -- but not  entirely unexpected.  Comet Hale-Bopp continues to approach the Sun - making the comet itself brighten, but now the Earth is moving away from it - making the comet appear to dim.  Experts disagree on just how bright Hale-Bopp will become. Optimists hope it will eventually outshine Comet Hyakutake, but some pessimists now expect no better than 3rd magnitude - hardly visible from well-lit cities. Comet Hale-Bopp still appears to be, however, a very large comet, and is sure to show much activity as it nears the Sun.  The comet should reach peak brightness in March 1997. This image was taken on August 18th and shows gas shed from the nucleus of the comet.
Stars in the Infrared Sky (1996-09-18)
What if you could see infrared light? Because this light is less absorbed by dust than visible light, you could peer into the center of our Milky Way Galaxy. The stars there are normally hidden from direct view by the interstellar dust clouds which line the Galactic plane. Above is a false color image of the entire sky made by the DIRBE instrument onboard NASA's COBE Satellite using infrared light with a wavelength of 3.5 microns - about 7 times longer than the wavelength of visible light. The galactic plane runs horizontally along the middle of the image. At this wavelength, the cool stars in our galaxy shine brightly and can be seen to define the plane of the Milky Way and the central bulge. Interplanetary dust, which tends to lie along the plane of our own solar system, scatters sunlight and emits radiation at these wavelengths too. The faint glow it produces results in the "S" shape apparent in this infrared all-sky view.
The Moon and All the Crashes (1996-09-19)
A clear blue summer sky finally grows dark and the new telescope, hastily set up in the backyard, generates excitment and anticipation. "I bought it for the kids ...", Dad assures himself as he over-anxiously supervises the two young boys' efforts to center a bright, first quarter Moon, in the finder. The evening's first target acquired, James adjusts the focus knob and falls silent. Suddenly, "Wow, looks just like on Apollo 13!". His younger brother Christopher takes his turn. "Do you see the Moon?", James asks, eager to provide guidance based on his own observing experience. Christopher echoes his brother's enthusiasm, "Yes, and I see all the crashes too!". The view they shared was not too different from the above image of a six day old moon, recorded in July 1995 by Rhode Island amateur astronomer Jim Hendrickson. Along the terminator, the line between lunar night and day, the shadows outline to advantage the spectacular craters -- caused by all the crashes.  Information: Thursday, September 26 - A Total Lunar Eclipse
Hurricane Fran's Approach (1996-09-20)
 Two weeks ago Hurricane Fran, pictured above, struck the east coast of the United States. Hurricanes are huge swirling storms with cloud systems typically larger than a state.  Tropical cyclones, called Hurricanes in Earth's Western Hemisphere and Typhoons in the Eastern Hemisphere, get their immense energy from warm evaporated ocean water.  As this water vapor cools and condenses, it heats the air, lowers pressure and hence causes cooler air to come swooshing in. Winds can reach over 150 miles per hour and become very dangerous.  Hurricane Fran, for example, killed more than 30 people and destroyed many million of dollars worth of property.  Much remains unknown about cyclones, including how they are formed and the exact path they will take.
The Ecliptic Plane (1996-09-21)
The Plane of the Ecliptic is illustrated in this Clementine star tracker camera image which reveals (from right to left) the Moon lit by Earthshine, the Sun's corona rising over the Moon's dark limb, and the planets Saturn, Mars, and Mercury. The ecliptic plane is defined as the imaginary plane containing the Earth's orbit around the Sun. In the course of a year, the Sun's apparent path through the sky lies in this plane. The planetary bodies of our solar system all tend to lie near this plane, since they were formed from the Sun's spinning, flattened, proto-planetary disk. The snapshot above nicely captures a momentary line-up looking out along this fundamental plane of our solar system.   Information: Thursday, September 26 - A Total Lunar Eclipse
The Equal Night (1996-09-22)
Today the Sun crosses the celestial equator heading south -- marking the Autumnal Equinox, the first day of Autumn. Equinox means equal night and with the Sun on the celestial equator, Earthlings will experience 12 hours of daylight and 12 hours of darkness. Then, for those in the northern hemisphere, the days will begin to grow shorter with the Sun marching lower in the sky as winter approaches. A few weeks after the Autumnal Equinox of 1994, the Crew of the Shuttle Endeavor recorded this image of the Sun poised above the Earth's limb. The glare illuminates Endeavor's vertical tail (pointing toward the Earth) along with radar equipment in the payload bay.  Information: Thursday, September 26 - A Total Lunar Eclipse
Venus: Earth's Cloudy Twin
Credit: (1996-09-23)
If Venus weren't so cloudy it would be more similar to Earth.  This picture by the Galileo spacecraft shows just how cloudy Venus is.  Venus is very similar to Earth in size and mass - and so is sometimes referred to as Earth's sister planet - but Venus has a quite different climate. Venus' thick clouds and closeness to the Sun (only Mercury is closer) make it the hottest planet - much hotter than the Earth. Humans could not survive there, and no life of any sort has ever been found. When Venus is visible it is usually the brightest object in the sky after the Sun and the Moon. More than 20 spacecraft have visited Venus including Venera 9, which landed on the surface, and Magellan, which used radar to peer through the clouds and make a map of the surface. This visible light picture of Venus was taken by the Galileo spacecraft now in orbit around Jupiter.  Many things about Venus remain unknown, including the cause of  mysterious bursts of radio waves.
Beneath Venus' Clouds (1996-09-24)
If the thick clouds covering Venus were removed, how would the surface appear? Using an imaging radar technique, the Magellan spacecraft was able to lift the veil from the Face of Venus and produce this spectacular high resolution imageof the planet's surface. Red, in this false-color map, represent mountains, while blue represents valleys This 3-kilometer resolution map is a composite of Magellan images compiled between 1990 and 1994. Gaps were filled in by the Earth-based Arecibo Radio Telescope. The large yellow/red area in the north is Ishtar Terra featuring Maxwell Montes, the largest mountain on Venus. The large highland regions are analogous to continents on Earth. Scientists are particularly interested in exploring the geology of Venus because of its similarity to Earth.  Information: Thursday, September 26 - A Total Lunar Eclipse
Bright Stars and Dark Clouds
Credit: (1996-09-25)
Did you ever feel like a black cloud was following you around? Well don't feel bad - this even happened to the bright young stars of the open cluster NGC 6520. On the left are the cluster's bright blue stars. They formed only millions of years ago - much more recently than our ancient Sun which formed billions of years ago. On the right is an absorption nebula from which the stars might have formed. This nebula contains much opaque dust which blocks visible light from the many stars that would have been seen in the background. The study of open clusters is valuable for many reasons which include the understanding star formation and the calibration of the distance scale of our universe.  Information: Thursday, September 26 - A Total Lunar Eclipse
Tonight: A Total Lunar Eclipse 
Credit and Copyright: (1996-09-26)
Tonight brings the last total lunar eclipse visible from North America until the year 2000 - with the Moon becoming completely immersed in Earth's shadow. The above time-lapse photograph shows a lunar eclipse that occurred in April 1993. Tonight's eclipse will begin at 8:12 pm Eastern Daylight Time, with totality extending from 10:19 pm to 11:29 pm. In North and South America, the Moon will be just rising at the beginning of the eclipse. In West Europe and Africa, tonight's lunar eclipse will be visible before the dawn of September 27th. The Moon is not expected to become completely dark - usually it has a slight red glow caused by sunlight refracted through the Earth's dusty atmosphere - but every lunar eclipse is slightly different. This year's eclipse will be enhanced by the proximity of bright Saturn just 3 degrees away.
Welcome Home Shannon Lucid
Credit: (1996-09-27)
Today is Shannon Lucid's first day on Planet Earth in six months. Her stay aboard Russia's Mir Space Station was of record length - the longest stay of any American in space ever. During her time in orbit around the Earth, Lucid, a biochemist, did many things including experiments on the effect of weightlessness on the human body. Pictured above, Lucid greets the astronaut that will replace her on Mir, John Blaha.
A Soyuz at Mir
Credit: (1996-09-28)
Pictured above is a three person Russian Soyuz capsule with wing-like solar panels extended, joined to the Mir space station. In Russian soyuz means "union" and indeed one of the milestones achieved by a Soyuz spacecraft was an orbital union with a US Apollo command module during the first international space mission (Apollo-Soyuz) in 1975. The Soyuz TM spacecraft are specially modified for use with the Mir as ferries for cosmonauts and astronauts and also as lifeboats, should the need arise. This image is from an electronic still camera used by the crew of the Space Shuttle Atlantis during their latest Mir visit to pick up astronaut Shannon Lucid and drop off John Blaha.
The X-Ray Moon
Credit: (1996-09-29)
This X-Ray image of the Moon was made by the orbiting Roentgen Observatory Satellite (ROSAT) in 1990. It shows three distinct regions: a bright X-ray sky, a bright part of the Moon, and a relatively dark part of the Moon. The bright X-ray sky is due to the diffuse cosmic X-ray background. The bright lunar crescent shines because it reflects X-rays emitted by the Sun. The dark lunar face is in shadow and so stands stands out from the relatively bright background - but, surprisingly it is not completely dark! Where do those X-rays from? They are currently thought to result from energetic particles from the solar wind bombarding the lunar surface.
Exploring The Universe With IUE 1978-1996
Credit: (1996-09-30)
How do planets, stars, and galaxies form? How do they evolve? The International Ultraviolet Explorer (IUE) satellite was launched in 1978 and operated by NASA/ ESA/ PPARC to help provide answers to some of the most fundamental questions about the contents of our universe. IUE served as a geostationary orbiting observatory for the next 18 years acquiring over 100,000 observations with its onboard ultraviolet spectrographs. Its prodigious scientific output is only hinted at by the all-sky plot above which shows the locations of IUE's many pointed observations over its long operational history. The brightness of a point on the sky represents the the number of IUE observations. The plot is in galactic coordinates (the plane of our Galaxy runs horizontally through the middle) and reveals the positions of distant quasars, galaxies, stars, star clusters, nebulae, novae, and supernovae - testifying to IUE's broad range of capabilities. The ecliptic plane is also visible running diagonally through the center, traced out by many observations of solar system objects. After over 18 years, IUE's science operations officially end today as the final commands are transmitted to the aging satellite by controllers at NASA's Goddard Space Flight Center. Astronomers from around the world whose careers have been touched by IUE have expressed their fond farewells to this most productive and longest lived astronomical satellite and their thanks to all who have made IUE's remarkable voyage of exploration possible.   News Flash:  BATSE Detects Huge Gamma Ray Burst
BATSE's Biggest Gamma Ray Burst (Yet)
Credit: (1996-10-01)
Something big exploded but astronomers have no idea what. On September 24th, the Burst and Transient Source Experiment (BATSE) onboard the orbiting Compton Gamma Ray Observatory recorded the most intense gamma ray burst in its five year history. During its mission, BATSE has recorded many gamma ray bursts - about one per day, but none were this powerful. Since their discovery over 25 years ago, the origin and even distance to gamma ray bursts remains hotly debated. Bursts are surely mysterious phenomena: they flash into existence suddenly dominating the entire gamma-ray sky, then typically fade in a few seconds never to be seen again. It is possible that this intense wave of gamma radiation caused other satellites to glitch and may even have been the cause of unusual noise in the Earth's atmosphere. If you know of such an anomaly, please report it.
Orion's Horsehead Nebula 
Credit: (1996-10-02)
The Horsehead Nebula is arguably the most famous nebula on the sky.  It is visible as the black indentation to the red emission nebula seen just to the right of center of the above photograph. The bright star near the center is located in the belt of the familiar constellation of Orion. The horse-head feature is dark because it is really an opaque dust cloud which lies in front of the bright red emission nebula. Like clouds in Earth's atmosphere, this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years, the internal motions of the cloud will alter its appearance. The emission nebula's red color is caused by electrons recombining with protons to form hydrogen atoms. Also visible in the picture are blue reflection nebulae, which preferentially reflect the blue light from nearby stars.
Three Views of Jupiter's Io
Credit: (1996-10-03)
The Galileo spacecraft orbiting Jupiter continues to return impressive results. The Galileo team has just released three more photographs of Jupiter's volcanic moon Io taken in June.  These three photos are reflected at the bottom of the above picture, digitally enhanced to better show important features. Some areas of Io, it now appears, are truly red, not the usual green and yellow hues recorded previously. In fact, the last major mission - Voyager - did not have cameras sensitive to red light. This red material appears to be associated with recent volcanic eruptions, and the red color appears to fade with time. Comparisons of these photos with 17-year old Voyager photos show that about a dozen surface regions -- each the size of Connecticut-- have been affected by Io's active volcanoes.
Globular Cluster Omega Centauri
Credit: (1996-10-04)
Does an old, red globular cluster have any hot, blue stars? The rightmost picture, taken by the Ultraviolet Imaging Telescope in ultraviolet light, shows that indeed it does. Pictured, Omega Centauri is the largest known globular cluster in our Galaxy, containing well over a million stars. Many of these stars are evident in the visible light photograph on the left. When photographed in ultraviolet light, however, different and less numerous stars emerge, as evident on the photograph on the right. Most of these stars are thought to have evolved past the current stage of our Sun. These stars no longer fuse hydrogen to helium in their core but rather fuse helium into carbon. These stars will soon shed their outer envelopes and end up as smoldering carbon embers known as white dwarf stars.
A Close-Up of the Horsehead Nebula 
Credit and Copyright: (1996-10-05)
1500 light years away lies a nebula of quite peculiar shape. How did the dark dust cloud shown above come to be shaped like a horse's head? Nobody knows! Barnard 33, as this region is known to some, is surely a dark dust cloud absorbing the light from the bright red emission nebula behind it. The Horsehead Nebula is also thought to be a region where low-mass stars form. But the reason for gross shapes in the universe is frequently poorly understood. Perhaps there is no simple explanation in this case. Some stars are thought to be efficient creators of dust, while others are much better at destroying it. The Horsehead Nebula's dust distribution might just be the result of a specific irregular distribution of stars and gas in its vicinity.
A Crescent Earth At Midnight
Credit: (1996-10-06)
The Earth's northern hemisphere appears outlined as a sunlit crescent in this dramatic view from the GOES 8 satellite. The image was made near midnight for the Geostationary Operational Environmental Satellite on June 22 this year, two days after the Summer Solstice. The Summer Solstice is the time of year when the sun reaches its greatest northern declination and the arctic regions near the top of the picture experience 24 hours of daylight. Looking south along the Earth's limb, atmospheric scattering of sunlight causes the bright crescent to be visible beyond areas directly illuminated by the sun.
Io's Shadow
Credit: (1996-10-07)
Caught in the act earlier this summer by the Hubble Space Telescope, the volcanic moon Io (above and right of center) and its shadow (black dot) are seen here against Jupiter's clouds. Io's shadow is 2,262 miles in diameter (about the size of Io) as it races across the swirling cloud tops at about 38,000 miles per hour. From our perspective in the inner Solar System, dramatic scenes like this one are possible when Jupiter, Io, and the Sun line up. What would this scene look like when viewed from Jupiter's cloud tops? As the shadow passed over Jupiter, for observers along the shadow's track, Io's disk would appear to eclipse the sun. The situation is familiar to those Earth Dwellers who have seen a Solar Eclipse - visible from along the track of the Moon's shadow passing across the surface of the Earth.
ROSAT Explores the X-Ray Sky (1996-10-08)
Launched in 1990, the orbiting ROSAT observatory explored the Universe by viewing the entire sky in x-rays - photons with about 1,000 times more energy than visible light. This ROSAT survey produced the sharpest, most sensitive image of the x-ray sky to date. The all-sky image is shown with the plane of our Milky Way Galaxy running horizontally through the center. Both x-ray brightness and relative energy are represented with red, green, and blue colors indicating three x-ray energy ranges (from lowest to highest). Bright x-ray spots near the galactic plane are within our own Milky Way. The brightest region (right of center) is toward the Vela Pulsar and the Puppis supernova remnant. Bright sources beyond our Galaxy are also apparent, notably the Virgo cluster of galaxies (near top right) and the Large Magellanic Cloud (LMC). The LMC is easy to find here as several of the black stripes (blank areas caused by missing data) seem to converge on its position (lower right). Over large areas of the sky a general diffuse background of x-rays dominates. Hot gas in our own Galaxy provides much of this background and gives rise to the grand looping structures visible in the direction of the galactic center (image center). Unresolved extragalactic sources also add to this background, particularly above and below the plane. Despite the x-ray sky's exotic appearance, a very familiar feature is visible - the gas and dust clouds which line the plane of our galaxy absorb x-rays as well as optical light and produce the dark bands running through the galactic center.
M31: The Andromeda Galaxy (1996-10-09)
Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about 2 million years for light to reach us from there. Much about M31 remains unknown, including why the center contains two nuclei.
Triton: Neptune's Largest Moon (1996-10-10)
Today marks the 150th anniversary of the discovery of Triton. On October 10 1846, William Lassell was observing the newly discovered planet Neptune. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well. Lassell soon proved the ring was product of his new telescope's distortion, but the satellite Triton remained. The above picture of Triton was taken in 1989 by the only spacecraft ever to pass Triton: Voyager 2. Voyager 2 found fascinating terrain, a thin atmosphere, and even evidence for ice volcanoes on this world of peculiar orbit and spin. Ironically, Voyager 2 also confirmed the existence of complete thin rings around Neptune - but these would have been quite invisible to Lassell!
The Double Nucleus of M31 (1996-10-11)
The center of M31 is twice as unusual as previously thought. In 1991 the Planetary Camera then onboard the Hubble Space Telescope pointed toward the center of our Milky Way's closest major galactic neighbor: Andromeda (M31). To everyone's surprise, M31's nucleus showed a double structure. The nuclear hot-spots are quite close together when considering Galactic distances: M31 is about 150,000 light years across while the above shows only the central 30 light-years. Subsequent ground-based observations have led to speculation that indeed two nuclei exist, are moving with respect to each other, that one nucleus is slowly tidally disrupting the other, and that one nucleus may be the remains of smaller galaxy "eaten" by M31. The nuclei of many galaxies, including M31, are known to be quite violent places, and the existence of massive black holes are frequently postulated to explain them.
The Water Vapor Channel (1996-10-12)
What alien planet's bizarre landscape lurks below these fiery-looking clouds? It's only Planet Earth, of course -- as seen on the Water Vapor Channel. Hourly, images like this one (shown in false color) are brought to you by the orbiting GOES 8 satellite's multi-channel imager. This instrument can produce images at the infrared wavelength of 6.7 microns or about 10 times the wavelength of visible light, recording radiation emitted by water vapor in the upper troposphere. Bright regions correspond to high concentrations of water vapor while dark spots are relatively dry areas. Atmospheric water vapor is invisible to the eye and produced by evaporation from the oceans. Convected upward in the tropical zones it affects the climate by contributing substantially to the greenhouse effect.
The Earth Also Rises (1996-10-13)
The Lunar Orbiter 1 spacecraft was launched in 1966 to map the lunar surface in preparation for the Apollo moon landings. NASA's plucky robotic explorer performed its job well and pioneered this classic view of the Earth poised above the lunar horizon. The first humans to directly witness a similar scene were the Apollo 8 astronauts. As they orbited the Moon in December of 1968 they also recorded Earth rise in a photograph that was to become one of the most famous images in history - a moving portrait of our world from deep space.