juliensimon/nasa-apod huggingface dataset:
Launch Plume: SpaceX Jellyfish (2026-03-19)

ven if you live with your head in the clouds, you won’t find a jellyfish like this one very often. The featured image shows a SpaceX Falcon 9 rocket launch from Cape Canaveral in Florida on March 4. The launch happened 52 minutes before sunrise, and the second stage rocket exhaust plume was high enough in the sky to catch the light of the rising sun, while the photographer was still in the dark. This combination of light and shadow, possible at dawn or dusk, makes the exhaust, mostly water vapor and carbon dioxide, appear as a glowing cloud. It only looks like it's going down, as the rocket follows the curvature of the Earth on its way to space. A related effect is the twilight phenomenon, which causes colorful contrails sometimes mistaken for UFOs. But, in case you are wondering: real jellyfish were sent to space by NASA in the 1990s as part of a science experiment.

Image credit: Michael Seeley
Spring Equinox at Teide Observatory (2026-03-20)

The defining astronomical moment of the equinox today is at 14:46 UTC (March 20). That's when the Sun crosses the celestial equator moving north in its yearly journey through planet Earth's sky, marking the beginning of spring for our fair planet in the northern hemisphere and fall in the southern hemisphere.  Then, day and night are nearly equal around the globe. In fact, both day and nighttime exposures from a spring equinox at the Observatorio del Teide in Tenerife, Canary Islands, Spain, are used in this composited skyscape. Over 1,000 images were taken with a fisheye lens and merged in the ambitious equinox project. The apparent motion of the Sun setting along the celestial equator on the equinox date follows the bright linear, diagonal track from the sequence of daytime exposures taken over 6 hours. After sunset, nighttime exposures recorded startrails, with the celestial equator as a linear track and concentric arcs circling the north celestial pole near Polaris at upper right and the south celestial pole beyond the lower left edge (and below the Teide horizon). The foreground includes the distant Teide volcano peak and the observatory's pyramid-shaped solar laboratory building.

Image credit: Juan Carlos Casado
Galaxies in the River: NGC 1300 and NGC 1297 (2026-03-21)

Spiral NGC 1300 and elliptical NGC 1297 are galaxies that lie on the banks of the southern constellation Eridanus (The River). At 70 million light-years distant or more, both are members of the Eridanus Galaxy Cluster. About 100,000 light-years across, at lower left in this sharp, galaxy group photo NGC 1300 is seen face-on with a prominent central bar and grand, sweeping spiral arms. Like other spiral galaxies, including our own barred spiral Milky Way Galaxy, NGC 1300 is thought to have a supermassive central black hole. A contrast in appearance and slightly more distant, NGC 1297 is the roughly spherical large elliptical galaxy near the top of the frame. With little active star formation, elliptical galaxies are composed of older populations of stars and are likely he result of multiple collisions and mergers with spirals.

Image credit: Dietmar Hager and Eric Benson
Leaving Earth (2026-03-22)

What would it look like to leave planet Earth? Such an event was recorded visually in great detail by the MESSENGER spacecraft as it swung back past the Earth in 2005 on its way in toward the planet Mercury. Earth can be seen rotating in this time-lapse video, as it recedes into the distance. The sunlit half of Earth is so bright that background stars are not visible. The robotic MESSENGER spacecraft orbit around Mercury from 2011 to 2015 has conducted the first complete map of the surface. On occasion, MESSENGER peered back at its home world. MESSENGER is one of the few things created on the Earth that will never return.  At the end of its mission, MESSENGER was purposefully crashed into Mercury's surface.   Almost Hyperspace: Random APOD Generator
Light Pillars and Orion over Mohe (2026-03-23)

What's happening at the end of that street?  Pictured here are not auroras but light pillars, a phenomenon typically much closer.  In most places on Earth, a lucky viewer can see a Sun pillar, a column of light appearing to extend up from the Sun caused by flat fluttering ice-crystals reflecting sunlight from the upper atmosphere.  Usually, these ice crystals evaporate before reaching the ground.  During freezing temperatures, however, flat fluttering ice crystals may form near the ground and are sometimes known as a crystal fog.  These small ice crystals may then reflect not the Sun but ground lights.  The featured image captured not only numerous light pillars but also the iconic constellation of Orion, and was taken in Mohe, the northernmost city in China.

Image credit: Jeff Dai
(TWAN)
A Gravity Map of Earth (2026-03-24)

Is gravity the same over the surface of the Earth?  No -- in some places you will feel slightly heavier than others.  The featured Earth map video shows in colors and exaggerated highs and lows where the gravitational field of Earth is relatively strong and weak.  A low spot, where you would feel slightly lighter, can be seen just off the coast of India, in blue, while a relative high occurs in the mountains of Chile in South America.  The cause of these irregularities does not always follow present surface features. Scientists hypothesize that other important factors lie in deep underground structures in Earth's mantle and may be related to the Earth's appearance in the distant past.  The featured map was composed from data taken by NASA's twin GRACE satellites that orbited the Earth from 2002 to 2017.  GRACE mapped Earth's gravity by carefully tracking tiny changes in the distance between the two satellites.
The Guardians of Rapa Nui beneath the Milky Way (2026-03-25)

In the words of today's astrophotographer, Rositsa Dimitrova, "What have these silent sentinels watched pass across the sky?" The volcanic mo'ai (meaning statue) of Anakena stand guard over Rapa Nui (Isla de Pascua, Easter Island), a Polynesian island (annexed by Chile in 1888) located thousands of kilometers off the coast of South America in the Pacific Ocean. Due to the island's remoteness, the mo'ai, with their backs to the dark ocean, are able to gaze upon a clear and vibrant night sky. Pictured, these larger-than-life statues stare at the bright band of the Milky Way, partly obscured by interstellar dust and blurred by Earth's clouds. Under such clear night skies, the Rapa Nui created observatories and used astronomical observations for navigation, calendar calibration, celebrations, and more. Images like this one remind us of the importance of dark skies, protecting the land underneath them, and preserving the culture that they inspire.

Image credit: Rositsa Dimitrova

Text:
Keighley Rockcliffe  
(NASA
GSFC, 
UMBC CSST, 
CRESST II)
Black Holes and Neutron Stars: 218 Mergers and Counting (2026-03-26)

What is the sound of two black holes merging in deep space? Sound waves don't propagate in vacuum, but gravitational waves do. In 2015 we were able to "hear" them for the first time and confirm one of Albert Einstein's theoretical predictions. Each square on the grid of the featured image represents one of the gravitational wave detections announced so far by the LIGO-VIRGO-KAGRA Collaboration. These plots show how the binary pair accelerates in their orbit around each other towards merger: the rising frequency effect is called a "chirp". Although there are significantly more neutron stars than black holes, most of the detections are binary black hole mergers. That happens because black holes are heavier and their signals are louder and can be seen farther away, resulting in more detections. These events are rare, and we don't expect to see one close by in our Galaxy any time soon. But they are happening continuously throughout the cosmos.
Hickson 44 in Leo (2026-03-27)

Scanning the skies for galaxies, Canadian astronomer Paul Hickson and colleagues identified some 100 compact groups of galaxies, now appropriately called Hickson Compact Groups. The four prominent galaxies seen in this intriguing telescopic skyscape are one such group, Hickson 44. The Hickson 44 galaxy group is about 100 million light-years distant, far beyond the foreground Milky Way stars, toward the northern springtime constellation Leo. The two spiral galaxies in the center of the image are edge-on NGC 3190 with distinctive, warped dust lanes, and S-shaped NGC 3187. Along with the bright elliptical, NGC 3193 (left) they are also known as Arp 316. The spiral toward the lower right corner is NGC 3185, the 4th member of the Hickson group. Like other galaxies in Hickson groups, these show signs of distortion and enhanced star formation, evidence of a gravitational tug of war that will eventually result in galaxy mergers on a cosmic timescale. The merger process is now understood to be a normal part of the evolution of galaxies, including our own Milky Way. For scale, NGC 3190 is about 75,000 light-years across at the estimated distance of Hickson 44.

Image credit: Peter Kennett
Robert Goddard and Nell (2026-03-28)

Robert H. Goddard, considered the father of modern rocketry, was born in Worcester Massachusetts in 1882. As a 16 year old, Goddard read H.G. Wells' science fiction classic "War Of The Worlds" and dreamed of space flight. By 1926 he had designed, built, and flown the world's first liquid fuel rocket. Launched 100 years ago on March 16, 1926 from his aunt Effie's farm in Auburn Massachusetts, the rocket, dubbed "Nell," rose to an altitude of 41 feet in a flight that lasted about 2 1/2 seconds. In this posed photo, Goddard stands next to the 10 foot tall rocket, holding the launch stand frame. To achieve a stable flight without the need for fins, the rocket's heavy motor was located at the top, fed by lines from liquid oxygen and gasoline fuel tanks at the bottom. Widely recognized as a gifted experimenter and engineering genius, his rockets were many years ahead of their time. Goddard was awarded over 200 patents in rocket technology, most of them after his death in 1945. A liquid fuel rocket constructed on principles developed by Goddard landed humans on the Moon in 1969.
A Message from Earth (2026-03-29)

What are these Earthlings trying to tell us?  The featured message was broadcast from Earth towards the globular star cluster M13 in 1974.  During the dedication of an upgrade to the Arecibo Observatory - then the largest single radio telescope in the world - a string of 1's and 0's representing the diagram was sent.  This attempt at extraterrestrial communication was mostly ceremonial - humanity regularly broadcasts radio and television signals out into space accidentally.  Even were this message received, M13 is so far away we would have to wait almost 50,000 years to hear an answer.  The featured message gives a few simple facts about humanity and its knowledge: from left to right are numbers from one to ten, atoms including hydrogen and carbon, some interesting molecules, DNA, a human with description, basics of our Solar System, and basics of the sending telescope.  Several searches for extraterrestrial intelligence are currently underway.   Explore the Universe: Random APOD Generator
Peculiar Elliptical Galaxy Centaurus A (2026-03-30)

What's happened to the center of this galaxy?  Dramatic dust lanes run across the center of unusual elliptical galaxy Centaurus A. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light.  This is particularly unusual as Cen A's older stars and oval shape are characteristic of a giant elliptical galaxy, a galaxy type typically low in dark dust.  Pictured in this deep image is a complex network of foreground gas and dust, as well as shells of dim stars and a jet projecting to the upper right.  Also known as NGC 5128, Cen A is surely the result of a galactic collision where many young dust-creating stars were formed.  However, details of the creation of Cen A's unusually active center and iconic central dust lanes are still being researched.  Cen A lies only 13 million light years away, making it the closest active galaxy.    Jigsaw Galaxy: Astronomy Puzzle of the Day

Image credit: SADR Observatory Team: 

J-C Dalouzy, 
P. Bazart, M. Dherbécourt, C. Humbert,  G. Leroy, 
J-P Quéau, H. Talbot, & E. Valin
Uranus's Largest Moon: Titania (2026-03-31)

Titania's tortured terrain is a mix of canyons, cliffs, and craters.  NASA's interplanetary robot spacecraft Voyager 2 passed the largest moon of Uranus in 1986 and took the feature picture. That the trenches of Titania resemble those on another moon of Uranus, Ariel, indicate that Titania underwent some violent surface event possibly related to water freezing and expanding in its distant past.  Although Titania is Uranus's largest moon, it is only about half the radius of Triton - the largest moon of Uranus's sister planet Neptune, which itself is slightly smaller than Earth's Moon.  Titania, discovered by William Herschel in 1787, is essentially a large dirty iceball that is composed of about half water-ice and half rock.  There is recent speculation that radioactive heating melts some underground ice into oceans.
The Claw and Bubble Nebulae (2026-04-01)

What unexpected things do you see when you look up at the night sky? Today’s image resembles an abstract painting, with large swaths of color strewn across a cosmic canvas seemingly without design. Despite the image's abstract nature, the human mind finds patterns, identifying a large claw reaching up towards a floating bubble. Embedded within these seemingly random structures are the physical laws that govern how light and matter interact. The Claw (Sh2-157) and Bubble (NGC 7635) Nebulae glow colors that are mapped to the yellow and blue shown, indicating the presence of hydrogen and oxygen ionized by the intense light emitted from stars several times the mass of the Sun. This image depicts both the chaos and structure of astronomical processes, showing that a common thread between art and science is to look for the unexpected.

Image credit: Richard Whitehead

Text:
Keighley Rockcliffe  
(NASA
GSFC, 
UMBC CSST, 
CRESST II)
Liftoff! Returning to the Moon (2026-04-02)

We are one small step closer to returning to the Moon. A new chapter in human exploration began yesterday when NASA's Artemis II launched aboard the Space Launch System (SLS) from Kennedy Space Center. Carrying four astronauts, the Orion spacecraft's planned lunar flyby will be the first in over half a century. This historic test flight, echoing the legacy of Apollo while pushing beyond it, will carry its crew farther from Earth than any humans since 1972, looping around the Moon before returning home. During the approximately ten-day journey, Orion's systems--from life support to navigation--will be tested in deep space, while astronauts observe the lunar surface, including shadowed regions of the far side rarely seen with such perspective. After looping around the Moon, the astronauts will return to Earth, ending their journey with a Pacific Ocean splashdown.

Image credit: NASA/Bill Ingalls; 
Text: Ogetay Kayali 
(MTU)
Caught in the Web: Visualization of a Black Hole Merger in the Tarantula Nebula (2026-04-03)

How can we see what is invisible? Black holes are not easy to see in the dark cosmic night, but astronomers can find them by analyzing their gravitational effects on matter, light and spacetime. The featured image shows an illustration that combines a simulation of a black hole binary system in its final "death-dance" with an astrophotography image of the Tarantula Nebula in the background. Even though black holes don't emit light, they distort the path of light rays, acting like a gravitational lens. As a result, the nebula appears extremely distorted, forming Einstein rings and multiple images.  Tarantula Nebula lies in the Large Magellanic Cloud, a dwarf galaxy that is one of the satellite galaxies of the Milky Way, 160,000 light-years away. That is more than 1,000 times closer than any of the binary black hole mergers detected so far. We'll probably never detect a merger so close to home!

Image credit: Carl Knox
Hello World (2026-04-04)

From pole to pole our fair planet is captured in this snapshot from space, an evocative image from a window of the Orion spacecraft Integrity. From the spacecraft's perspective the Sun is moving behind Earth's bright limb along the lower right. Africa and the Iberian peninsula are in view on the pale blue planet's surface, while aurorae crown Earth's south and north poles at top right and bottom left. Commander Reid Wiseman took the historic picture on Artemis II mission flight day 2 (April 2), after the completion of the planned translunar injection burn. That burn boosted the spacecraft out of Earth orbit, sending Integrity and crew on a trajectory that will take them around the Moon and back again. That's a journey humans last made over 50 years ago. (Editor's note: Venus is photobombing Wiseman's historic pic. Currently appearing in our western skies after sunset, the inner planet is in the frame below and right of Earth's bright limb, immersed in a faint band of zodiacal light.)
NGC 3310: A Starburst Spiral Galaxy (2026-04-05)

The party is still going on in spiral galaxy NGC 3310.  Roughly 100 million years ago, NGC 3310 likely collided with a smaller galaxy causing the large spiral galaxy to light up with a tremendous burst of star formation.  The changing gravity during the collision created density waves that compressed existing clouds of gas and triggered the star-forming party.  The featured image from the Gemini North Telescope shows the galaxy in great detail, color-coded so that pink highlights gas while white and blue highlight stars.  Some of the star clusters in the galaxy are quite young, indicating that starburst galaxies may remain in star-burst mode for quite some time.  NGC 3310 spans about 50,000 light years, lies about 50 million light years away, and is visible with a small telescope towards the constellation of Great Bear Ursa Major.

Image credit: AAO ITSO Office, 
Gemini Obs./AURA & 
T. A. Rector 
(U. Alaska Anchorage)
The Path of Artemis II (2026-04-06)

Why doesn't Artemis II land on the Moon? The main reason is that Artemis II is primarily a test mission designed to make a future Artemis missions -- which will land humans on the Moon -- better prepared.  Similarly, NASA's Apollo 8 and Apollo 10 went right near the Moon as tests before Apollo 11 -- which landed.  As the trajectory in the featured animated video shows, Artemis II will loop around both the Earth and the Moon before returning to the Earth about 10 days after launch. The Artemis II mission will take humans outside the Earth's magnetosphere for the first time since the Apollo missions 50 years ago.  In the video, particles from the solar wind are shown as streaks, while the Earth's reacting magnetosphere is shown in flickering green.  The Earth's magnetosphere is important in deflecting powerful particles arriving from the Sun as well as creating picturesque auroras visible from the Earth's surface.    Explore the Universe: Random APOD Generator
IC 4592: The Blue Horsehead Reflection Nebula (2026-04-07)

Do you see the horse's head?   What you are seeing is not the famous Horsehead nebula toward Orion, but rather a fainter nebula that only takes on a familiar form with deeper imaging.  The main part of the here-imaged molecular cloud complex is  reflection nebula IC 4592.  Reflection nebulas are made up of very fine dust that normally appears dark but can look quite blue when reflecting the visible light of energetic nearby stars.  In this case, the source of much of the reflected light is a star at the eye of the horse.  That star is part of Nu Scorpii, one of the brighter star systems toward the constellation of the Scorpion (Scorpius).   A second reflection nebula dubbed IC 4601 is visible surrounding two stars just below the image center.  The featured picture was taken from  Sawda Natheel in  Qatar.   Jigsaw Nebula: Astronomy Puzzle of the Day

Image credit: Rabeea Alkuwari
Earthset (2026-04-08)

And to all of you down there on Earth and around Earth, we love you, from the Moon. We will see you on the other side, said Artemis II pilot Victor Glover on  April 6th at 6:44pm ET  as 8.3 billion minus four people and one Earth  set  below the Moon's horizon. The Orion spacecraft, Integrity, then traveled behind the Moon as part of its seven-hour lunar flyby.  The crew characterized  never-before-seen regions of  the far side of the Moon,  which is  puzzlingly less volcanically active  than the near side. New observations of  crater peaks, floors, terraces, and rings  preserved on the lunar surface will  help piece together the impact history of the Solar System.  Among many other surface characterizations, the crew observed one of the Moon's best-preserved basins,  the Orientale basin,  and identified  two new craters.  As  Earth rose  above the Moon’s horizon and Integrity began its return home, Artemis II mission specialist Christina Koch powerfully summarized humanity’s grander mission: ...we will always choose Earth. We will always choose each other.
Destruction of Comet C/2026 A1 (MAPS) (2026-04-09)

As the crew of Artemis II travelled towards the Moon this week, Comet C/2026 A1 (MAPS) was expected to have its closest approach to the Sun on Monday. At this point, comet and Sun would be closer than half the distance separating the Earth and Moon. The comet did not survive; the featured video was made with 40 hours of data and shows the comet plunging toward the Sun, like a moth to a flame. Observing the comet so close to our bright star requires a coronagraph, an instrument that blocks the Sun and is used for studies of its corona. This composite video combines, starting from the outside, views from: the wider angle coronagraph (blue) and the narrower angle coronagraph (red), both on NASA's Solar and Heliospheric Observatory, and NASA's Solar Dynamics Observatory (black). We can see the comet approaching the sun, stretching, disappearing behind the coronagraph's occulting disk and reappearing as a cloud of debris that dissipates.
Exploring the Antennae (2026-04-10)

Some 60 million light-years away in the southerly constellation Corvus, two large galaxies are colliding. Stars in the two galaxies, cataloged as NGC 4038 and NGC 4039, very rarely collide in the course of the ponderous cataclysm that lasts for hundreds of millions of years. But the galaxies' large clouds of molecular gas and dust often do, triggering furious episodes of star formation near the center of the cosmic wreckage. Spanning over 50 thousand light-years, this stunning telescopic frame also reveals new star clusters and matter flung far from the scene of the accident by gravitational tidal forces. The remarkably sharp ground-based image follows the faint tidal tails and distant background galaxies in the field of view. The suggestive overall visual appearance of the extended arcing structures gives the galaxy pair, also known as Arp 244, its popular name - The Antennae.   Artemis II: Splashdown

Image credit: Mike Selby
Artemis II: Flight Day 6 (2026-04-11)

On flight day 6 (April 6) the Artemis II mission achieved a historic lunar flyby. Rounding the lunar far side, the deep space maneuver marked humanity's first venture to the Moon since Apollo 17 in 1972. The Orion spacecraft Integrity reached a maximum distance of nearly 407,000 kilometers, and the Artemis II crew, Reid Wiseman, Victor Glover, and Christina Koch, and Jeremy Hansen, set the record for the farthest distance from Earth traveled by any human since the Apollo 13 crew in 1970. From behind the Moon on flight day 6, a solar array wing camera recorded this space age selfie, framing the spacecraft and lunar far side. Planet Earth, home to the Artemis II crew, is the small, bright crescent beyond the lunar limb. The crew safely returned home on Artemis II mission flight day 10.   Artemis II: Splashdown