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  Where Your Elements Came From Image Credit & Copyright: NASA GSFC's SVS Explanation: The hydrogen in your body and present in every molecule of water came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen. Much of the iron in your body was made during supernovas of stars that occurred long ago and far away. The gold in your jewelry was likely made from neut...

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  Comet NEOWISE Rising Over the Adriatic Sea Image Credit & Copyright: Paolo Girotti Explanation: This sight was worth getting out of bed early. Just over four years ago, Comet C/2020 F3 (NEOWISE) rose before dawn to the delight of northern sky enthusiasts awake that early. Up before sunrise on July 8th, the featured photographer was able to capture in dramatic fashion one of the few comets visible to the unaided eye this century, an inner-Solar System intruder that has become known as the Gr...

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  Contemplating the Sun Image Credit & Copyright: Steven Gilbert Explanation: Have you contemplated your home star recently? Featured here, a Sun partially eclipsed on the top left by the Moon is also seen eclipsed by earthlings contemplating the eclipse below. This spectacular menagerie of silhouettes was taken in 2012 from the Glen Canyon National Recreation Area near Page, Arizona, USA, where park rangers and astronomers expounded on the unusual event to interested gatherers. Also, faintly...

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  Curious Cometary Knots in the Helix Nebula Image Credit: NASA, ESA, CSA, STScI, JWST; Processing: A. Pagan (STScI) Explanation: What causes unusual knots of gas and dust in planetary nebulas? Seen also in the Ring Nebula, the Dumbbell Nebula and NGC 2392, the knots' existence was not initially predicted, and their origins are still not well understood. Pictured here is a fascinating image of part of the Helix Nebula by the James Webb Space Telescope showing tremendous detail in infrared lig...

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  A Fire Rainbow over West Virginia Image Credit & Copyright: Christa Harbig Explanation: What's happening to this cloud? Ice crystals in a distant cirrus cloud are acting like little floating prisms. Known informally as a fire rainbow for its flame-like appearance, a circumhorizon arc appears parallel to the horizon. For a circumhorizontal arc to be visible, the Sun must be at least 58 degrees high in a sky where cirrus clouds present below -- in this case cirrus fibratus. The numerous,...

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  Red Sun through Wildfire Smoke Image Credit & Copyright: Debra Ceravolo Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II) Explanation: This could be the view from an exoplanet orbiting around a red dwarf star, but it is our own Sun. This image was taken on July 22, 2026, in the Okanagan region in the Canadian province of British Columbia. Wildfire smoke from the Pacific Northwest acted as a solar filter, allowing the photographer to take this photo of the Sun directly. Several sunspots ar...

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  Simulation TNG50: A Galaxy Cluster Forms Video Credit: IllustrisTNG Project; Visualization: Dylan Nelson (Max Planck Institute for Astrophysics) et al. Music: Symphony No. 5 (Ludwig van Beethoven), via YouTube Audio Library Explanation: How do clusters of galaxies form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. One famous effort is TNG50 from IllustrisTNG, an upgrade of the famous Illustris Simulation. The first part of the fe...

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  The Large Magellanic Cloud Image Credit & Copyright: Monica Mesa Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II) Explanation: Have you ever seen another galaxy with your own eyes? The featured image shows the Large Magellanic Cloud (LMC), one of the closest neighbors of our Milky Way. If you are anywhere south of latitude 20° N (but the further south, the better), you can see it with the unaided eye if you go to a dark sky location, away from big cities and light polution. It is a dwarf...

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  The Corona Australis Molecular Cloud and the Chandelier Cluster Image Credit: DES/DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURA Image Processing: T.A. Rector (UAA/NOIRLab), R. Colombari & M. Zamani (NOIRLab) Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II) Explanation: The Southern Crown (Corona Australis) dazzles with young and ancient celestial jewels. The Corona Australis Cloud is a collage of reflection and emission nebulae on the left of today’s image. At 430 light years away, this c...

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  Galaxy NGC 474: Shells and Star Streams Image Credit & License: CFHT, Coelum, MegaCam, J.-C. Cuillandre (CFHT) & G. A. Anselmi (Coelum) Explanation: What's happening to galaxy NGC 474? The multiple layers of emission appear strangely complex given the relatively featureless appearance of the elliptical galaxy in less deep images. The cause of the shells is a topic of research, but they are possibly tidal tails related to debris left over from absorbing numerous small galaxies in the...

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  Three Galaxies in Pavo Image Credit & Copyright: Mike Selby Explanation: Some 190 million light-years away, far beyond the bright stars and nebulae of the Milky Way, these three galaxies are drawn together by gravity in a mesmerizing cosmic dance. Clearly distorted by galactic-scale gravitational interactions, large spiral galaxies NGC 6769 and NGC 6770 are seen face-on, with luminous galactic disks scarred by obscuring interstellar dust lanes. Their young blue star clusters along drawn out...

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  AR 4478: Giant Sunspot Group Image Credit & Copyright: Alfredo Vidal Pérez Explanation: Right now, one of the largest sunspot groups in recent history is crossing the Sun. Active Region 4478 is not only big -- it's violent, showing tangled magnetic fields capable of throwing off huge clouds of particles into the Solar System. Some of these CMEs might impact the Earth. At the extreme, these solar storms could cause some Earth-orbiting satellites to malfunction, the Earth's atmosphere...

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  A Martian Eclipse: Phobos Crosses the Sun Video Credit: NASA, JPL-Caltech, ASU MSSS, SSI Explanation: What's that passing in front of the Sun? It looks like a moon, but it can't be Earth's Moon, because it isn't round. It's the Martian moon Phobos. The featured video was taken from the surface of Mars in 2022 by the Perseverance rover. Phobos, at 11.5 kilometers across, is 150 times smaller than Luna (our moon) in diameter, but also 50 times closer to its parent planet. In f...

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  APOD is 30 Years Old Today Image Credit: Pixelization of Van Gogh's The Starry Night by Dario Giannobile https://apod.nasa.gov/apod/ap250616.html #APOD

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  NGC 602 and Beyond Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA) - ESA/Hubble Collaboration Explanation: The clouds may look like an oyster, and the stars like pearls, but look beyond. Near the outskirts of the Small Magellanic Cloud, a satellite galaxy some 200 thousand light-years distant, lies 5 million year young star cluster NGC 602. Surrounded by natal gas and dust, NGC 602 is featured in this stunning Hubble image of the region. Fantastic ridges and swept back shapes...

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  A Message from Earth Image Credit: Frank Drake et al., Arecibo Observatory; License: Arne Nordmann (Wikimedia) Explanation: 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...

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  Comet R3 PanSTARRS Before Rigel Image Credit & Copyright: Jakub Kuřák & Martin Mašek (FZU of the Czech Academy of Sciences) Explanation: Which way is Comet R3 PanSTARRS going? Not towards the star at the top of the image, because that is Rigel, which, being far in the background, is unrelated to the comet. Not through the nebula in the image middle, because that is the Witch Head Nebula and it, too, is far in the distance -- but not far from Rigel.  Not into northern skies because over...

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  Comet R3 PanSTARRS and Orion Image Credit & Copyright: Luc Perrot (TWAN) Explanation: Orion never had a sword like this. As Comet C/2025 R3 (PanSTARRS) heads out of the inner Solar System, it is putting on quite a show for long exposure cameras. Currently seen toward the constellation of Orion the Hunter, the distant Orion Nebula is visible on the upper right. Comet R3 PanSTARRS is now showing two distinct tails: a short dust tail pointing toward the top of the image and a long and wavy ion...

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  The Retrograde Dance of Saturn and Neptune Image Credit & Copyright: Tunç Tezel (TWAN) Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II) Explanation: What does it mean for Saturn and Neptune to be in retrograde? Featured is a composite of images taken over 34 nights from May 2025 to February 2026 tracing Saturn (brighter, foreground) and Neptune (dimmer, background). Over that time, the two planets exhibited retrograde motion, meaning they appeared to move backward in the sky. Thi...

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  Messier Craters in Stereo Image Credit: Apollo 11, NASA; Stereo Image Copyright Patrick Vantuyne Explanation: Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier from his famous 18th century catalog. His name is also given to these two large and remarkable craters on the Moon. Standouts in the dark, smooth lunar Sea of Fertility or Mare Fecunditatis, Messier (left) and Messier A have dimensions of 15 by 8 and 16 by 11 kilome...

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  Hello World Image Credit: NASA, Reid Wiseman, Artemis II Explanation: 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. Commande...

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  Supernova in a Sideways Spiral Video Credit: Hunter Outten & Kaleb Jordan Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II) Explanation: A long time ago, in a distant galaxy, a massive star was destroyed in a supernova explosion. The light of this event travelled for tens of millions of years and reached Earth last week as Supernova 2026kid. The featured video shows a time-lapse over three nights of the host galaxy NGC 5907, an edge-on spiral also known as the Splinter or Knife Edge Galax...

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  The ISS Transits the Moon Image Credit & Copyright: Sébastien Borie Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II) Explanation: Nope, that is not an alien spaceship landing on the Moon! This is an image of the International Space Station (ISS) as it begins to transit in front of the Moon. The ISS is in low-Earth orbit (LEO) where it wizzes around the Earth every 90 minutes. Orbiting the Earth 16 times per day for 25 years, the ISS has photobombed many familiar celestial objects...

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  Full Moonlight Image Credit & Copyright: Zhengjie Wu and Jeff Dai (TWAN) Explanation: The Full Moon is the brightest lunar phase, and tonight you can stand in the light of the first Full Moon of 2026. In fact, the Moon's full phase occurs on January 3 at 10:03 UTC, while only about 7 hours later planet Earth reaches its 2026 perihelion, the closest point in its elliptical orbit around the Sun, at 17:16 UTC. January's Full Moon was also not far from its own perigee, or closest appro...

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  Waves on Titan Video Credit: Una Schneck Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II) Explanation: Have you ever thought about surfing on an alien world? We can now expand the search for the perfect wave from Earth to the rest of the Solar System, and beyond. Scientists have developed a new model for simulating waves on other planets. Titan is one of the 274 confirmed moons of Saturn to date, and the only object in the solar system (besides Earth) known to have liquid lakes and seas on i...

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  Orion over Mount Teide Image Credit & Copyright: Marcin Rosadziński Explanation: Orion is rarely seen like this. To achieve this majestic vista, you need a camera capable of taking such long duration exposures that faint features in the night sky become revealed. Iconic nebulas that appear include the Orion Nebula, the Flame Nebula, and Barnard's Loop. For contrast, it also helps to have a volcano on the foreground, in this case the Teide volcano on Tenerife on the Canary Islands of Spa...

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  Superplumes Inside Earth Image Credit & License: Sanne Cottaar via Wikimedia Commons Explanation: Why are there huge, unusual masses inside the Earth? No one is sure. By noting how earthquakes rumble through our planet's interior, humanity has discovered two deep structures that appear to have unusual temperatures and/or chemical compositions. One hypothesis holds that the superplumes are sunken debris left over from the Earth-shattering collision that created Earth's Moon about 4.5...

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  Trifid Pillars and Jets Image Credit: NASA, ESA, STScI; Processing: J. DePasquale (STScI) Explanation: Dust pillars are like interstellar mountains. They survive because they are more dense than their surroundings, but they are slowly being eroded away by a hostile environment. Visible in the featured picture by the Hubble Space Telescope is the end of a huge gas and dust pillar in the Trifid Nebula (M20), punctuated by a smaller pillar pointing up and an unusual jet pointing to the upper left....

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  Seeing Titan Image Credit: VIMS Team, Univ. Arizona, U. Nantes, ESA, NASA Explanation: Shrouded in a thick atmosphere, the surface of Saturn's largest moon, Titan, is really hard to see. Small particles suspended in Titan's upper atmosphere cause an almost impenetrable haze, strongly scattering light at visible wavelengths and hiding surface features from prying eyes. Still, Titan's surface is better imaged at infrared wavelengths, where scattering is weaker and atmospheric absorpti...

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  The Moon, Venus, and the Pleiades Image Credit & Copyright: Gianni Tumino Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II) Explanation: No, Earth did not recently acquire six more moons! Today’s APOD is a combination of images following the Moon, Venus, and the Pleiades across a southern Sicilian sky as twilight turned to evening on April 19. From 2023 to 2029, the Pleiades' and the Moon “visit" each other once per month due to the Pleiades' location in the ecliptic...