juliensimon/nasa-apod huggingface dataset:
Lightning Eclipse from the Planet of the Goats (2017-07-16)

Thunderstorms almost spoiled this view of the spectacular 2011 June 15 total lunar eclipse. Instead, storm clouds parted for 10 minutes during the total eclipse phase and lightning bolts contributed to the dramatic sky. Captured with a 30-second exposure the scene also inspired one of the more memorable titles (thanks to the astrophotographer) in APOD's now 22-year history.  Of course, the lightning reference clearly makes sense, and the shadow play of the dark lunar eclipse was widely viewed across planet Earth in Europe, Africa, Asia, and Australia. The picture itself, however, was shot from the Greek island of Ikaria at Pezi. That area is known as "the planet of the goats" because of the rough terrain and strange looking rocks.    Details: Total Solar Eclipse on 2017 August 21

Image credit: Chris Kotsiopoulos
(GreekSky)
Moon Shadow versus Sun Reflection (2017-07-17)

What are those lights and shadows crossing the Earth? As the featured five-second time-lapse video progresses, a full day on planet Earth is depicted as seen from Japan's Himawari-8 satellite in geostationary orbit high above the Pacific Ocean. The Sun rises to the right and sets to the left, illuminating the half of Earth that is most directly below.  A reflected image of the Sun -- a Sun glint -- is visible as a bright spot that moves from right to left. More unusual, though, is the dark spot that moves from the lower left to upper right That is the shadow of the Moon, and it can only appear when the Moon goes directly between the Earth and the Sun. Last year, on the day these images were taken, the most deeply shadowed region experienced a total eclipse of the Sun.  Next month a similarly dark shadow will sweep right across the USA.    Follow APOD on: Facebook,  Google Plus,  Instagram, or Twitter
Thunder Moon over Pisa (2017-07-18)

What's wrong with this picture?  If you figure it out, you may then realize where the image was taken.  The oddity lies actually in one of the buildings -- it leans. The Leaning Tower of Pisa has been an iconic legend since shortly after its construction began in the year 1173.  Now part of a UNESCO World Heritage Site, folklore holds that Galileo used the leaning tower to dramatically demonstrate the gravitational principle that objects of different mass fall the same.  Between the Leaning Tower of Pisa on the right and Pisa Cathedral and the Pisa Baptistery  on the left, a full "Thunder" moon was visible last week when the image composite was taken.  Using modern analyses, the tower has been successfully stabilized and, barring the unexpected, should hold its present tilt for the next 200 years.    Indonesia: New APOD Mirror Site in Indonesian

Image credit: Marco Meniero
Ireson Hill on Mars (2017-07-19)

What created this unusual hill on Mars? Its history has become a topic of research, but its shape and two-tone structure makes it one of the more unusual hills that the robotic Curiosity rover on Mars has rolled near.  Dubbed Ireson Hill, the mound rises about 5 meters high and spans about 15 meters across.  Ireson Hill is located on the Bagnold Dune field on the slope of Mount Sharp in Gale Crater on Mars. The featured 41-image panorama has been horizontally compressed to include the entire hill. The image was taken on February 2 and released last week. Because Mars is moving behind the Sun as seen from the Earth, NASA will soon stop sending commands to its Martian orbiters and rovers until about August 1.    Explore the Universe: Random APOD Generator
IC 1396: Emission Nebula in Cepheus (2017-07-20)

Stunning emission nebula IC 1396 mixes glowing cosmic gas and dark dust clouds in the high and far off constellation of Cepheus. Energized by the bright central star seen here, this star forming region sprawls across hundreds of light-years, spanning over three degrees on the sky while nearly 3,000 light-years from planet Earth. Among the intriguing dark shapes within IC 1396, the winding Elephant's Trunk nebula lies just below center. Stars could still be forming inside the dark shapes by gravitational collapse. But as the denser clouds are eroded away by powerful stellar winds and radiation, any forming stars will ultimately be cutoff from the reservoir of star stuff.  The gorgeous color view is a composition of image data from narrowband filters, mapping emission from the nebula's atomic oxygen, hydrogen, and sulfur into blue, green, and red hues.

Image credit: César Blanco
González
Phobos: Moon over Mars (2017-07-21)

A tiny moon with a scary name, Phobos emerges from behind the Red Planet in this timelapse sequence from the Earth-orbiting Hubble Space Telescope. Over 22 minutes the 13 separate exposures were captured near the 2016 closest approach of Mars to planet Earth. Martians have to look to the west to watch Phobos rise, though. The small moon is closer to its parent planet than any other moon in the Solar System, about 3,700 miles (6,000 kilometers) above the Martian surface. It completes one orbit in just 7 hours and 39 minutes. That's faster than a Mars rotation, which corresponds to about 24 hours and 40 minutes. As a result, seen from the surface of Mars speeding Phobos rises above the western horizon 2 times in a Martian day. Still, Phobos is doomed.
Apollo 11: Catching Some Sun (2017-07-22)

Bright sunlight glints and long dark shadows mark this image of the lunar surface. It was taken July 20, 1969 by Apollo 11 astronaut Neil Armstrong, the first to walk on the Moon. Pictured is the mission's lunar module, the Eagle, and spacesuited lunar module pilot Buzz Aldrin unfurling a long sheet of foil also known as the Solar Wind Composition Experiment. Exposed facing the Sun, the foil trapped particles streaming outward in the solar wind, catching a sample of material from the Sun itself. Along with moon rocks and lunar soil samples, the solar wind collector was returned for analysis in earthbound laboratories.
Mercury as Revealed by MESSENGER (2017-07-23)

Mercury had never been seen like this before.  In 2008, the robotic MESSENGER spacecraft buzzed past Mercury for the second time and imaged terrain mapped previously only by comparatively crude radar.  The featured image was recorded as MESSENGER looked back 90 minutes after passing, from an altitude of about 27,000 kilometers. Visible in the image, among many other newly imaged features, are unusually long rays that appear to run like meridians of longitude out from a young crater near the northern limb.  MESSENGER entered orbit around Mercury in 2011 and finished its primary mission in 2012, but took detailed measurements until 2015, at which time it ran out of fuel and so was instructed to impact Mercury's surface.    New Moon Tonight: The next New Moon will block the Sun.
A Hybrid Solar Eclipse over Kenya (2017-07-24)

Chasing solar eclipses can cause you to go to the most interesting places and meet the most interesting people.  Almost.  For example, chasing this eclipse brought this astrophotographer to Kenya in 2013. His contact, a member of the Maasai people, was to pick him up at the airport, show him part of southern Kenya, and even agreed to pose in traditional warrior garb on a hill as the hopefully spectacular eclipse set far in background.  Unfortunately, this contact person died unexpectedly a week before the astrophotographer's arrival, and so he never got to participate in the shoot, nor know that the resulting image went on to win an international award for astrophotography.  Pictured in 2013 from Kenya, the Moon covers much of the Sun during a hybrid eclipse, a rare type of solar eclipse that appears as total from some Earth locations, but annular in others. During the annular part of the eclipse, the Moon was too far from the Earth to block the entire Sun.  Next month a total solar eclipse will cross the USA.   Share the Sky: NASA creates new Open API for APOD

Image credit: Eugen Kamenew
(Kamenew Photography)
Int-Ball Drone Activated on the Space Station (2017-07-25)

What if you were followed around by a cute floating ball that kept taking your picture? Then you might be an astronaut on today's International Space Station (ISS).  Designed by the Japan Aerospace Exploration Agency (JAXA), the JEM Internal Ball Camera -- informally "Int-Ball" -- is a bit larger than a softball, can float and maneuver by itself but also be controlled remotely, can take high resolution images and videos, and is not related to Hello Kitty.  Int-Ball was delivered to the ISS in early June and is designed to allow ground-control to increase the monitoring of ISS equipment and activities while decreasing time demands on human astronauts. Int-Ball moves by turning on small internal fans and sees with a camera located between its two dark eyes.
The Milky Way over Monument Valley (2017-07-26)

You don't have to be at Monument Valley to see the Milky Way arc across the sky like this -- but it helps. Only at Monument Valley USA would you see a picturesque foreground that includes these iconic rock peaks called buttes. Buttes are composed of hard rock left behind after water has eroded away the surrounding soft rock.  In the featured image taken a month ago, the closest butte on the left and the butte to its right are known as the Mittens, while Merrick Butte can be seen farther to the right. Green airglow fans up from the horizon.  High overhead stretches a band of diffuse light that is the central disk of our spiral Milky Way Galaxy. The band of the Milky Way can be spotted by almost anyone on almost any clear night when far enough from a city and surrounding bright lights, but a sensitive digital camera is needed to capture these colors in a dark night sky.

Image credit: Tom Masterson
A Sagittarius Triplet (2017-07-27)

These three bright nebulae are often featured on telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula above and left of center, and colorful M20 near the bottom of the frame. The third emission region includes NGC 6559, right of M8 and separated from the larger nebula by a dark dust lane. All three are stellar nurseries about five thousand light-years or so distant. Over a hundred light-years across the expansive M8 is also known as the Lagoon Nebula. M20's popular moniker is the Trifid. Glowing hydrogen gas creates the dominant red color of the emission nebulae. In striking contrast, blue hues in the Trifid are due to dust reflected starlight. The colorful composite skyscape was recorded with two different telescopes to capture a widefield image of the area and individual close-ups at higher resolution.

Image credit: Josep Drudis
Noodle Mosaic of Saturn (2017-07-28)

On April 26 the Cassini spacecraft swooped toward Saturn on the first of its Grand Finale dives between Saturn and rings. In this long, thin, noodle mosaic, a rapid series of 137 low resolution images captured by Cassini's wide-angle camera track its progress across the gas giant's swirling cloud tops. The mosaic projection maps the arc along Saturn's atmospheric curve on to a flat image plane. At top, the first mosaic panel is centered at 90 degrees north, about 72,400 kilometers above Saturn's dark north polar vortex. As the mosaic progresses it narrows, the pixel scale shrinking from 8.7 kilometers to 1 kilometer per pixel. For the last panel, the spacecraft is 8,374 kilometers above a region 18 degrees north of Saturn's equator. Frame orientation changes near the bottom as Cassini rotates to maneuver its large, dish-shaped, high-gain antenna forward, providing a shield before crossing Saturn's ring plane.
Aurora Slathers up the Sky (2017-07-29)

Like salsa verde on your favorite burrito, a green aurora slathers up the sky in this June 25 snapshot from the International Space Station. About 400 kilometers (250 miles) above Earth, the orbiting station is itself within the upper realm of the auroral displays. Aurorae have the signature colors of excited molecules and atoms at the low densities found at extreme altitudes. Emission from atomic oxygen dominates this view. The tantalizing glow is green at lower altitudes, but rarer reddish bands extend above the space station's horizon. The orbital scene was captured while passing over a point south and east of Australia, with stars above the horizon at the right belonging to the constellation Canis Major, Orion's big dog. Sirius, alpha star of Canis Major, is the brightest star near the Earth's limb.
A Total Eclipse at the End of the World (2017-07-30)

Would you go to the end of the world to see a total eclipse of the Sun? If you did, would you be surprised to find someone else there already? In 2003, the Sun, the Moon, Antarctica, and two photographers all lined up in Antarctica during an unusual total solar eclipse.  Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon.  One of the treasures collected was the featured picture -- a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse.  As the image was taken, both the Moon and the Sun peeked together over an Antarctic ridge.  In the sudden darkness, the magnificent corona of the Sun became visible around the Moon.  Quite by accident, another photographer was caught in one of the images checking his video camera.   Visible to his left are an equipment bag and a collapsible chair.  A more easily visible solar eclipse will occur in about three weeks and be visible from the USA.

Image credit: Fred Bruenjes
(moonglow.net)
Pluto Flyover from New Horizons (2017-07-31)

What if you could fly over Pluto -- what might you see? The New Horizons spacecraft did just this in 2015 July as it shot past the distant world at a speed of about 80,000 kilometers per hour. Recently, many images from this spectacular passage have been color enhanced, vertically scaled, and digitally combined into the featured two-minute time-lapse video. As your journey begins, light dawns on mountains thought to be composed of water ice but colored by frozen nitrogen.  Soon, to your right, you see a flat sea of mostly solid nitrogen that has segmented into strange polygons that are thought to have bubbled up from a comparatively warm interior.  Craters and ice mountains are common sights below. The video dims and ends over terrain dubbed bladed because it shows 500-meter high ridges separated by kilometer-sized gaps.  Although the robotic New Horizons spacecraft has too much momentum ever to return to Pluto, it has now been targeted at Kuiper Belt object 2014 MU 69, which it should shoot past on New Year's Day 2019.   Follow APOD on: Facebook,  Google Plus,  Instagram, or Twitter
Perseid Meteors over Turkey (2017-08-01)

The Perseid Meteor Shower, usually the best meteor shower of the year, will peak late next week.   A person watching a clear sky from a dark location might see a bright meteor every minute.  These meteors are actually specks of rock that have broken off Comet Swift-Tuttle and continued to orbit the Sun until they vaporize in Earth's atmosphere.  The featured composite image shows a outburst of Perseids as they appeared over Turkey during last year's meteor shower.  Enough meteors were captured to trace the shower's radiant back to the constellation of Perseus on the far left.  The tail-end of the Perseids will still be going during the total solar eclipse on August 21, creating a rare opportunity for some lucky astrophotographers to image a Perseid meteor during the day.   Memorable APOD: Meteor Showers

Image credit: Tunç Tezel
The Dust Monster in IC 1396 (2017-08-02)

Is there a monster in IC 1396?  Known to some as the Elephant's Trunk Nebula, parts of gas and dust clouds of this star formation region may appear to take on foreboding forms, some nearly human.  The only real monster here, however, is a bright young star too far from Earth to hurt us.  Energetic light from this star is eating away the dust of the dark cometary globule near the top of the featured image.  Jets and winds of particles emitted from this star are also pushing away ambient gas and dust.  Nearly 3,000 light-years distant, the relatively faint IC 1396 complex covers a much larger region on the sky than shown here, with an apparent width of more than 10 full moons.   APOD Retrospective: August 2

Image credit: Anis Abdul
Pelican Nebula Close-up (2017-08-03)

The prominent ridge of emission featured in this vivid skyscape is designated IC 5067. Part of a larger emission region with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years and follows the curve of the cosmic pelican's head and neck. Fantastic, dark shapes inhabiting the view are clouds of cool gas and dust sculpted by energetic radiation from young, hot, massive stars. But stars are also forming within the dark shapes. Twin jets emerging from the tip of the long, dark tendril left of center are the telltale signs of an embedded protostar cataloged as Herbig-Haro 555 (HH 555). In fact, other Herbig-Haro objects indicating the presence of protostars are found within the frame. The Pelican Nebula itself, also known as IC 5070, is about 2,000 light-years away. To find it, look northeast of bright star Deneb in the high flying constellation Cygnus.

Image credit: Sara Wager
North North Temperate Zone Little Red Spot (2017-08-04)

On July 11, the Juno spacecraft once again swung near the turbulent Jovian cloud tops. On its seventh orbital closest approach this perijove passage brought Juno within 3,500 kilometers of the Solar System's largest planetary atmosphere. Near perijove the rotating JunoCam was able to record this stunning, clear view of one of Jupiter's signature vortices. About 8,000 kilometers in diameter, the anticyclonic storm system was spotted in Jupiter's North North Temperate Zone in the 1990s. That makes it about half the size of an older and better known Jovian anticyclone, the Great Red Spot, but only a little smaller than planet Earth. At times taking on reddish hues, the enormous storm system is fondly known as a North North Temperate Zone Little Red Spot.
Gravity's Grin (2017-08-05)

Albert Einstein's general theory of relativity, published over 100 years ago, predicted the phenomenon of gravitational lensing. And that's what gives these distant galaxies such a whimsical appearance, seen through the looking glass of X-ray and optical image data from the Chandra and Hubble space telescopes. Nicknamed the Cheshire Cat galaxy group, the group's two large elliptical galaxies are suggestively framed by arcs. The arcs are optical images of distant background galaxies lensed by the foreground group's total distribution of gravitational mass. Of course, that gravitational mass is dominated by dark matter. The two large elliptical "eye" galaxies represent the brightest members of their own galaxy groups which are merging. Their relative collisional speed of nearly 1,350 kilometers/second heats gas to millions of degrees producing the X-ray glow shown in purple hues. Curiouser about galaxy group mergers? The Cheshire Cat group grins in the constellation Ursa Major, some 4.6 billion light-years away.
Milky Way and Exploding Meteor (2017-08-06)

Next weekend the Perseid Meteor Shower reaches its maximum.  Grains of icy rock will streak across the sky as they evaporate during entry into Earth's atmosphere.  These grains were shed from Comet Swift-Tuttle.  The Perseids result from the annual crossing of the Earth through Comet Swift-Tuttle's orbit, and are typically the most active meteor shower of the year.  Although it is hard to predict the level of activity in any meteor shower, in a clear dark sky an observer might see a meteor a minute.  This year's Perseids peak nearly a week after full Moon, and so some faint meteors will be lost to the lunar skyglow.  Meteor showers in general are best be seen from a relaxing position, away from lights.  Featured here is a meteor caught exploding during the 2015 Perseids above Austria next to the central band of our Milky Way Galaxy.   Follow APOD on: Facebook,  Google Plus,  Instagram, or Twitter

Image credit: Andr� van der Hoeven
Spiral Galaxy NGC 1512: The Inner Ring (2017-08-07)

Most galaxies don't have any rings -- why does this galaxy have two?  To begin, the bright band near NGC 1512's center is a nuclear ring, a ring that surrounds the galaxy center and glows brightly with recently formed stars. Most stars and accompanying gas and dust, however, orbit the galactic center in a ring much further out -- here seen near the image edge. This ring is called, counter-intuitively, the inner ring.  If you look closely, you will see this the inner ring connects ends of a diffuse central bar that runs horizontally across the galaxy. These ring structures are thought to be caused by NGC 1512's own asymmetries in a drawn-out process called secular evolution.  The gravity of these galaxy asymmetries, including the bar of stars, cause gas and dust to fall from the inner ring to the nuclear ring, enhancing this ring's rate of star formation.  Some spiral galaxies also have a third ring -- an outer ring that circles the galaxy even further out.   Two Weeks from Today: An American total eclipse of the Sun
Density Waves in Saturn's Rings from Cassini (2017-08-08)

What causes the patterns in Saturn's rings?  The Cassini spacecraft, soon ending its 13 years orbiting  Saturn,  has sent back another spectacular image of Saturn's immense ring system in unprecedented detail.  The physical cause for some of Saturn's ring structures is not always understood.   The cause for the beautifully geometric type of ring structure shown here in ring of Saturn, however, is surely a  density wave.  A small moon systematically perturbing the orbits of ring particles circling Saturn at slightly different distances causes such a density wave bunching.  Also visible on the lower right of the image is a bending wave, a vertical wave in ring particles also caused by the gravity of a nearby moon.  Cassini's final orbits are allowing a series of novel scientific measurements and images of the Solar System's  most grand ring system.    Open Science: Browse 1,500+ codes in the Astrophysics Source Code Library
August's Lunar Eclipse (2017-08-09)

August's Full Moon is framed in this sharp, high dynamic range composition. Captured before sunrise on August 8 from Sydney, Australia, south is up and the curve of the Earth's dark, umbral shadow is at the left, near the maximum phase of a partial lunar eclipse. Kicking off the eclipse season, this time the Full Moon's grazing slide through Earth's shadow was visible from the eastern hemisphere. Up next is the much anticipated total solar eclipse of August 21. Then, the New Moon's shadow track will include North America, the narrow path of totality running coast to coast through the United States.
Night of the Perseids (2017-08-10)

This weekend, meteors will rain down near the peak of the annual Perseid Meteor Shower. Normally bright and colorful, the Perseid shower meteors are produced by dust swept up by planet Earth from the orbit of Comet Swift-Tuttle. They streak from a radiant in Perseus, above the horizon in clear predawn skies. Despite interfering light from August's waning gibbous moon, this year's Perseids will still be enjoyable, especially if you can find yourself in an open space, away from city lights, and in good company. Frames used in this composite view capture bright Perseid meteors from the 2016 meteor shower set against a starry background along the Milky Way, with even the faint Andromeda Galaxy just above center. In the foreground, astronomers of all ages have gathered on a hill above the Slovakian village of Vrchtepla.

Image credit: Petr Horálek