juliensimon/nasa-apod huggingface dataset:
Philae Lander Found on Comet 67P (2016-09-12)

A little spacecraft that was presumed lost has now been found. In 2014, the Philae lander slowly descended from its parent Rosetta spacecraft to the nucleus of Comet C67/P Churyumov-Gerasimenko. At the surface, after a harpoon malfunction, the lander bounced softly twice and eventually sent back images from an unknown location.  Earlier this month, though, Rosetta swooped low enough to spot its cub.  The meter-sized Philae is seen on the far right of the main image, with inset images showing both a zoom out and a zoom in. At the end of this month, Rosetta itself will be directed to land on 67P, but Rosetta's landing will be harder and, although taking unique images and data, will bring the mission  to an end.    Free Download: APOD 2017 Calendar: NASA Images

Image credit: ESA, 
Rosetta, 
MPS, OSIRIS; 
UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA/Navcam
NGC 1672: Barred Spiral Galaxy from Hubble (2016-09-13)

Many spiral galaxies have bars across their centers.  Even our own Milky Way Galaxy is thought to have a modest central bar. Prominently barred spiral galaxy NGC 1672, featured here, was captured in spectacular detail in an image taken by the orbiting Hubble Space Telescope. Visible are dark filamentary dust lanes, young clusters of bright blue stars, red emission nebulas of glowing hydrogen gas, a long bright bar of stars across the center, and a bright active nucleus that likely houses a supermassive black hole.  Light takes about 60 million years to reach us from NGC 1672, which spans about 75,000 light years across. NGC 1672, which appears toward the constellation of the Dolphinfish (Dorado), is being studied to find out how a spiral bar contributes to star formation in a galaxy's central regions.    Follow APOD on: Facebook,  Google Plus,  Instagram, or Twitter

Image credit: Steve Cooper
The North and South of Jupiter (2016-09-14)

A wide, looping orbit brought Juno close to Jupiter on August 27. As the spacecraft swung around the giant planet's poles JunoCam acquired these premier direct polar views, a change from the usual nearly equatorial perspective of outbound spacecraft and the telescopes of planet Earth. The sunlit side of Jupiter's north polar region (left) was imaged about 125,000 kilometers from the cloud tops, two hours before Juno's closest approach. An hour after close approach the south polar region was captured from 94,500 kilometers away. Strikingly different from the alternating light-colored zones and darker belts girdling more familiar equatorial regions, the polar region clouds appear more convoluted and mottled by many clockwise and counterclockwise rotating storm systems. Another 35 close orbital flybys are planned during the Juno mission.
Retrograde Mars and Saturn (2016-09-15)

Wandering Mars and Saturn have spent much of this year remarkably close in planet Earth's night sky. In a sequence of exposures spanning mid-December 2015 through the beginning of this week, this composited skyview follows their time together, including both near opposition, just north of bright star Antares near the Milky Way's central bulge. In the corresponding video, Saturn's apparent movement is seen to be back and forth along the flattened, compact loop, while Mars traces the wider, reversing S-shaped track from upper right to lower left through the frame. To connect the dots and dates just slide your cursor over the picture (or follow this link). It looks that way, but Mars and Saturn don't actually reverse direction along their orbits. Instead, their apparent backwards or retrograde motion with respect to the background stars is a reflection of the orbital motion of the Earth itself. Retrograde motion can be seen each time Earth overtakes and laps planets orbiting farther from the Sun, the Earth moving more rapidly through its own relatively close-in orbit.

Image credit: Tunç Tezel
Full Moon over Brno (2016-09-16)

After sunset this gorgeous full moon rose over Brno city in the Czech Republic on July 20, 2016. The panoramic image was made during a celebration of the 47th anniversary of the Apollo 11 lunar landing. A series of exposures captures the yellow hued lunar disk against the fading colors of twilight, with the 14th century Spilberk castle illuminated in the foreground.  Of course, tonight's full moon is called the Harvest Moon. The closest full moon to the northern hemisphere's autumnal equinox, its traditional name has long been celebrated in story and song. Tonight's full lunar phase also coincides with a subtle, penumbral lunar eclipse, the Moon passing only through the Earth's diffuse, outer shadow.

Image credit: Petr Horálek
M33: Triangulum Galaxy (2016-09-17)

The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy and astronomers in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from planet Earth, this sharp composite image nicely shows off M33's blue star clusters and pinkish star forming regions along the galaxy's loosely wound spiral arms. In fact, the cavernous NGC 604 is the brightest star forming region, seen here at about the 1 o'clock position from the galaxy center. Like M31, M33's population of well-measured variable stars have helped make this nearby spiral a cosmic yardstick for establishing the distance scale of the Universe.

Image credit: Giovanni Benintende
Starry Night Scavenger Hunt (2016-09-18)

Did you know that van Gogh's painting Starry Night includes Comet Hale-Bopp? Hopefully not, because it doesn't. But the featured image does.  Although today's picture may appear at first glance to be a faithful digital reproduction of the original Starry Night, actually it is a modern rendition meant not only to honor one of the most famous paintings of the second millennium, but to act as a scavenger hunt. Can you find, in the featured image, a comet, a spiral galaxy, an open star cluster, and a supernova remnant?  Too easy? OK, then find, the rings of Supernova 1987A, the NGC 2392, the Crab Nebula, Thor's Helmet, the Cartwheel Galaxy, and the Ant Nebula. Still too easy? Then please identify any more hidden images not mentioned here -- and there are several -- on APOD's main discussion board: The Asterisk.  Finally, the collagist has graciously hidden APOD's 10th anniversary Vermeer photomontage just to honor APOD. (Thanks!)    Free Download: APOD 2017 Calendar: NASA Images

Image credit: Ronnie Warner
50,000 Kilometers over the Sun (2016-09-19)

What's happening at the edge of the Sun? Although it may look like a monster is rampaging, what is pictured is actually only a monster prominence -- a sheath of thin gas held above the surface by the Sun's magnetic field. The solar event was captured just this past weekend with a small telescope, with the resulting image then inverted and false-colored. As indicated with illustrative lines, the prominence rises over 50,000 kilometers above the Sun's surface, making even our 12,700-diameter Earth seem small by comparison. Below the monster prominence is active region 12585, while light colored filaments can be seen hovering over a flowing solar carpet of fibrils. Filaments are actually prominences seen against the disk of the Sun, while similarly, fibrils are actually spicules seen against the disk.  Energetic events like this are becoming less common as the Sun evolves toward a minimum in its 11-year activity cycle.    Free Download: APOD 2017 Calendar: NASA Images

Image credit: Pete Lawrence
The Helix Nebula in Infrared (2016-09-20)

What makes this cosmic eye look so red?  Dust. The featured image from the robotic Spitzer Space Telescope shows infrared light from the well-studied Helix Nebula (NGC 7293) a mere 700 light-years away in the constellation of the Water Carrier Aquarius. The two light-year diameter shroud of dust and gas around a central white dwarf has long been considered an excellent example of a planetary nebula, representing the final stages in the evolution of a Sun-like star. But the Spitzer data show the nebula's central star itself is immersed in a surprisingly bright infrared glow. Models suggest the glow is produced by a dust debris disk. Even though the nebular material was ejected from the star many thousands of years ago, the close-in dust could have been generated by collisions in a reservoir of objects analogous to our own solar system's Kuiper Belt or cometary Oort cloud. Had the comet-like bodies formed in the distant planetary system, they would have survived even the dramatic late stages of the star's evolution.   Follow APOD on: Facebook,  Google Plus,  Instagram, or Twitter
Zooming in on Star Cluster Terzan 5 (2016-09-21)

Globular clusters once ruled the Milky Way.  Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy.  Today, there are less than 200 left.  Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center.  Surviving relics are older than any Earth fossil, older than any other structures in our Galaxy, and limit the universe itself in raw age.  There are few, if any, young globular clusters in our Milky Way Galaxy because conditions are not ripe for more to form. The featured video shows what it might look like to go from the Earth to the globular cluster Terzan 5, ending with a picture of the cluster taken with the Hubble Space Telescope.  This star cluster was recently found to contain not only stars formed in the early days of our Milky Way Galaxy, but also, quite surprisingly, others that formed in a separate burst of star formation about 7 billion years later.
Sunset at Edmontonhenge (2016-09-22)

On September 18, the setting Sun illuminated both sides of the steep brick and steel canyon otherwise known as Jasper Avenue in downtown Edmonton, Alberta, Canada, planet Earth. The Stonehenge-like alignment is captured from the middle of the road in this daring snapshot. In Edmonton streets are laid out on a grid almost oriented along the cardinal directions, so aligned Edmonton sunsets (and sunrises) occur along the nearly east-west streets twice a year, close to the Equinox. In fact, at today's Equinox, the Sun crosses the celestial equator at 1421 UT and on this day the Sun will rise due east and set due west, bringing approximately equal hours of day and night to denizens of planet Earth. The September Equinox marks the astronomical beginning of Fall in the north and Spring in the southern hemisphere.

Image credit: Luca Vanzella
Harvest Moon Eclipse (2016-09-23)

A Harvest Moon rises over Sesimbra Castle south of Lisbon in this impressive series of telephoto exposures. Captured at its full phase, the golden Moon was also gliding through the Earth's more diffuse outer shadow during September's penumbral lunar eclipse. The eclipse shading is subtle compared to a total lunar eclipse. Still, the penumbral shadow does darken the Moon's upper limb, the pale shadow receding as the Moon climbs into Portugal's evening sky. In this eclipse timelapse the effect of sunlight and earthshadow on the Moon looks remarkably like the coloring of light and shadow along the illuminated castle walls.

Image credit: Miguel Claro
Heart and Soul and Double Cluster (2016-09-24)

This rich starfield spans almost 10 degrees across the sky toward the northern constellations Cassiopeia and Perseus. On the left, heart-shaped cosmic cloud IC 1805 and IC 1848 are popularly known as the Heart and Soul nebulae. Easy to spot on the right are star clusters NGC 869 and NGC 884 also known as h and Chi Perseii, or just the Double Cluster. Heart and Soul, with their own embedded clusters of young stars a million or so years old, are each over 200 light-years across and 6 to 7 thousand light-years away. In fact, they are part of a large, active star forming complex sprawling along the Perseus spiral arm of our Milky Way Galaxy. The Double Cluster is located at about the same distance as the Heart and Soul nebulae. Separated by only a few hundred light-years, h and Chi Perseii are physically close together, and both clusters are estimated to be about 13 million years old. Their proximity and similar stellar ages suggest both clusters are likely a product of the same star-forming region.

Image credit: Adrien Klamerius
Saturn from Above (2016-09-25)

This image of Saturn could not have been taken from Earth.  No Earth based picture could possibly view the night side of Saturn and the corresponding shadow cast across Saturn's rings.  Since Earth is much closer to the Sun than Saturn, only the day side of the ringed planet is visible from the Earth.  In fact, this image mosaic was taken earlier this year by the robotic Cassini spacecraft now orbiting Saturn, just before filming a 44-hour video of Saturn rotating.  The beautiful rings of Saturn are seen in full expanse, while cloud details are visible including the polar hexagon surrounding the north pole. The Cassini mission is now in its final year as the spacecraft is scheduled to be programmed to dive into Saturn's atmosphere next September.
Gaia: Here Comes the Sun (2016-09-26)

What would it look like to return home from outside our galaxy? Although designed to answer greater questions, recent data from ESA's robotic Gaia mission is helping to provide a uniquely modern perspective on humanity's place in the universe.  Gaia orbits the Sun near the Earth and resolves star's positions so precisely that it can determine a slight shift from its changing vantage point over the course of a year, a shift that is proportionately smaller for more distant stars -- and so determines distance.  In the first sequence of the video, an illustration of the Milky Way is shown that soon resolves into a three-dimensional visualization of Gaia star data.  A few notable stars are labelled with their common names, while others stars are labelled with numbers from Gaia's catalog. Eventually the viewer arrives at our home star Sol  (the Sun), then resolving the reflective glow of its third planet: Earth. The featured video is based on just over 600,000 stars, but Gaia is on track to measure the parallax distances to over one billion stars over its planned five year mission.
Jupiter's Europa from Spacecraft Galileo (2016-09-27)

What mysteries might be solved by peering into this crystal ball?  In this case, the ball is actually a moon of Jupiter, the crystals are ice, and the moon is not only dirty but cracked beyond repair.  Nevertheless, speculation is rampant that oceans exist under Europa's fractured ice-plains that could support life.  This speculation was bolstered again this week by released images from the Hubble Space Telescope indicating that plumes of water vapor sometimes emanate from the ice-crusted moon -- plumes that might bring microscopic sea life to the surface. Europa, roughly the size of Earth's Moon, is pictured here in natural color as photographed in 1996 by the now-defunct Jupiter-orbiting Galileo spacecraft. Future observations by Hubble and planned missions such as the James Webb Space Telescope later this decade and a Europa flyby mission in the 2020s may further humanity's understanding not only of Europa and the early Solar System but also of the possibility that life exists elsewhere in the universe.   Free Download: APOD 2017 Calendar: NASA Images
NGC 3576: The Statue of Liberty Nebula (2016-09-28)

What's happening in the Statue of Liberty nebula?  Bright stars and interesting molecules are forming and being liberated. The complex nebula resides in the star forming region called RCW 57.  This image showcases dense knots of dark interstellar dust, bright stars that have formed in the past few million years, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3576, also known as NGC 3582 and NGC 3584, uncovered at least 33 massive stars in the end stages of formation, and the clear presence of the complex carbon molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are thought to be created in the cooling gas of star forming regions, and their development in the Sun's formation nebula five billion years ago may have been an important step in the development of life on Earth. The featured image was taken at the Cerro Tololo Inter-American Observatory in Chile.   Free Download: APOD 2017 Calendar: NASA Images

Image credit: S. Mazlin, 
J. Harvey, 
R. Gilbert, 
& D. Verschatse  
(SSRO/PROMPT/UNC)
Five Hundred Meter Aperture Spherical Telescope (2016-09-29)

The Five-hundred-meter Aperture Spherical Telescope (FAST) is nestled within a natural basin in China's remote and mountainous southwestern Guizhou province. Nicknamed Tianyan, or the Eye of Heaven, the new radio telescope is seen in this photograph taken near the start of its testing phase of operations on September 25. Designed with an active surface for pointing and focusing, its enormous dish antenna is constructed with 4,450 individual triangular-shaped panels. The 500 meter physical diameter of the dish makes FAST the largest filled, single dish radio telescope on planet Earth. FAST will explore the Universe at radio frequencies, detecting emission from hydrogen gas in the Milky Way and distant galaxies, finding faint galactic and extragalactic pulsars, and searching for potential radio signals from extraterrestrials.

Image credit: Jeff Dai
Lynds Dark Nebula 1251 (2016-09-30)

Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region, drifting above the plane of our Milky Way galaxy. Across the spectrum, astronomical explorations of the obscuring interstellar clouds reveal energetic shocks and outflows associated with newborn stars, including the telltale reddish glow from scattered Herbig-Haro objects seen in this sharp image. Distant background galaxies also lurk on the scene, visually buried behind the dusty expanse. The deep telescopic field of view spans about two full moons on the sky, or 17 light-years at the estimated distance of LDN 1251.

Image credit: Lynn Hilborn
Rosetta's Farewell (2016-10-01)

After closely following comet 67P/Churyumov-Gerasimenko for 786 days as it rounded the Sun, the Rosetta spacecraft's controlled impact with the comet's surface was confirmed by the loss of signal from the spacecraft on September 30, 2016. One of the images taken during its final descent, this high resolution view looks across the comet's stark landscape. The scene spans just over 600 meters (2,000 feet), captured when Rosetta was about 16 kilometers from the comet's surface. Rosetta's descent to the comet brought to an end the operational phase of an inspirational mission of space exploration. Rosetta deployed a lander to the surface of one of the Solar System's most primordial worlds and witnessed first hand how a comet changes when subject to the increasing intensity of the Sun's radiation.  The decision to end the mission on the surface is a result of the comet's orbit now taking it to the dim reaches beyond Jupiter where there would be a lack of power to operate the spacecraft. Mission operators also faced an approaching period where the Sun would be close to line-of-sight between Earth and Rosetta, making radio communications increasingly difficult.

Image credit: ESA, 
Rosetta, 
MPS, OSIRIS;
UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
Aurora Over White Dome Geyser (2016-10-02)

Sometimes both heaven and Earth erupt. Colorful aurorae erupted unexpectedly a few years ago, with green aurora appearing near the horizon and brilliant bands of red aurora blooming high overhead.  A bright Moon lit the foreground of this picturesque scene, while familiar stars could be seen far in the distance.  With planning, the careful astrophotographer shot this image mosaic in the field of White Dome Geyser in Yellowstone National Park in the western USA. Sure enough, just after midnight, White Dome erupted -- spraying a stream of water and vapor many meters into the air. Geyser water is heated to steam by scalding magma several kilometers below, and rises through rock cracks to the surface. About half of all known geysers occur in Yellowstone National Park. Although the geomagnetic storm that created these aurorae has since subsided, eruptions of White Dome Geyser continue about every 30 minutes.   Free Download: APOD 2017 Calendar: NASA Images

Image credit: Robert Howell
Explore Rosetta's Comet (2016-10-03)

What would it be like to fly around a comet nucleus? To find out, just wait for your WebGL-compatible browser to load a detailed digital model of Comet 67P and then -- go exploring! With a standard mouse, the left button allows you to rotate the comet, the right button allows you to move the comet around, and the scroll wheel allows you to zoom in.  ESA's robotic Rosetta spacecraft orbited Comet C67/P Churyumov-Gerasimenko from mid-2014 until last Friday, when, after a remarkable and successful mission, it was intentionally set down on the surface and powered down.  Among many notable scientific achievements, Rosetta allowed humanity to better understand where comet jets form on comets as they near the Sun.   Transparent Science: Browse 1,350+ codes in the Astrophysics Source Code Library
Nest of the Eagle Nebula (2016-10-04)

What surrounds the famous Eagle Nebula?  The inside of the Eagle Nebula contains eggs -- evaporating gaseous globules -- that typically reside in tremendous pillars of gas and dust and where stars form. This image, though, dramatically captures the area surrounding the Eagle Nebula, showing not only the entire Eagle shape, but also enormous volumes of glowing gas and dark dust.  Cataloged as M16, the Eagle emission nebula lies about 6,500 light years away and is visible with binoculars toward the constellation of the Serpent (Serpens). The image spans about 80 light years around the nebula. The iconic center of the Eagle Nebula has been the focus of many observational efforts both from the ground and orbiting observatories.    Follow APOD on: Facebook,  Google Plus,  Instagram, or Twitter

Image credit: Chris Hendren
A Crumbling Layered Butte on Mars (2016-10-05)

What is this unusual mound on Mars? NASA's Curiosity rover rolling across Mars has come across a group of these mounds that NASA has labelled Murray Buttes. Pictured is a recently assembled mosaic image of one of the last of the buttes passed by Curiosity on its way up Mt. Sharp -- but also one of the most visually spectacular. Ancient water-deposited layers in relatively dense -- but now dried-out and crumbling -- windblown sandstone tops the 15-meter tall structure. The rim of Gale crater is visible in the distance.  Curiosity continues to accumulate clues about how Mars changed from a planet with areas wet and hospitable to microbial life to the dry, barren, rusted landscape seen today.
Trifid, Lagoon, and Mars (2016-10-06)

Bright nebulae and star clusters along this 5 degree wide field of view are popular stops on telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. Cataloged by 18th century French astronomer Charles Messier, M20, the colorful Trifid Nebula, and M8, the expansive Lagoon Nebula, are at upper left and center. Both are well-known star forming regions about 5,000 light-years distant. Just passing through the same field of view on September 29, the yellowish star lined up with M8 and M20 at the lower right is actually Mars, close to 8.8 light-minutes from Earth on that date. That distance is nearly equivalent to 1 astronomical unit or the distance from Earth to Sun. Mars is overexposed in the image, with visible diffraction spikes created by the telescope mirror supports. Of course, Mars has long been known to wander through planet Earth's night skies.

Image credit: Mohammad Nouroozi