NGC 3310: A Starburst Spiral GalaxyThe 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…Read More

Hello WorldFrom 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…Read More

Caught in the Web: Visualization of a Black Hole Merger in the Tarantula NebulaHow 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…Read More

Liftoff! Returning to the MoonWe 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…Read More

The Claw and Bubble NebulaeWhat 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 f…Read More

Uranus’s Largest Moon: TitaniaTitania’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…Read More

Peculiar Elliptical Galaxy Centaurus AWhat’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…Read More

A Message from EarthWhat 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…Read More

Robert Goddard and NellRobert 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,…Read More

Hickson 44 in LeoScanning 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…Read More

Black Holes and Neutron Stars: 218 Mergers and CountingWhat 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…Read More

The Guardians of Rapa Nui beneath the Milky WayIn 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 Ahu Tongariki stand guard over Rapa Nui (Isla de Pascua, Easter Island), a Polynesian island (annexed by Chile in 1888) located thousands…Read More

A Gravity Map of EarthIs 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…Read More

Light Pillars and Orion over MoheWhat’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…Read More

Leaving EarthWhat 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…Read More

Galaxies in the River: NGC 1300 and NGC 1297Spiral 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…Read More

Spring Equinox at Teide ObservatoryThe 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.…Read More

Launch Plume: SpaceX Jellyfishven 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 c…Read More

Cygnus and the Solitary TreeA lone tree stands in a quiet meadow in Guadalajara, Spain, silhouetted against the Cygnus region rising above like flames in the night sky. This deep night skyscape is a composite of exposures that reveals a range of brightness and color human eyes can’t quite see on their own. Spanning over a thousand times the…Read More

The Tadpoles of IC 410This telescopic close-up shows off the central regions of otherwise faint emission nebula IC 410, captured under backyard skies. Presented in a Hubble color palette, the image combines visible broadband and narrowband data with data from the near-infrared. Below and right of center are two remarkable inhabitants of the…Read More

NGC 1566: The Spanish Dancer GalaxyIf not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe containing billions of stars and situated about 40 million light-years away toward the constellation of the Dolphinfish (Dorado), NGC 1566 presents a gorgeous face-on view. Classified as a grand design spiral, NGC…Read More

Equinox at the Pyramid of the Feathered SerpentTo see the feathered serpent descend the Mayan pyramid requires exquisite timing. You must visit El Castillo — in Mexico’s Yucatán Peninsula — near an equinox. Then, during the late afternoon if the sky is clear, the pyramid’s own shadows create triangles that merge into the famous illusion of a…Read More

A Year for K2-315bWant to visit a planet that has 3.14 days in a year? Then plan a trip to K2-315b, an earth-sized planet orbiting around a cool, red, M dwarf star about once every 3.14 days. The exoplanet’s discovery, based on publicly available data from the planet-hunting Kepler Space Telescope’s extended K2 mission, was announced in 2020.…Read More

Toolondo Totality TrailsIn this composited night skyscape, stacked exposures trace graceful star trails above Lake Toolondo, Victoria, Australia, planet Earth. Captured while the lunar eclipse of March 3 was in progress, the exposures used were made during the hour-long total eclipse phase. So faint star trails are easily visible along with the…Read More

CG 4: The Globule and the GalaxyIs this a cosmic monster ready to devour an unsuspecting galaxy? Thankfully, that is not the case. The red “monster” shown in the featured image is Cometary Globule CG 4, 1,300 light-years away in the Constellation Puppis. CG 4 is a molecular cloud, where hydrogen becomes cold enough to form molecules that can be…Read More

Sky Glows over Paranal ObservatoryAre lasers from giant telescopes being used to defend the Earth? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some directions, Earth atmosphere-induced fluctuations in starlight can indicate how the air mass over a telescope is changing,…Read More

The Cranium Nebula from the Webb TelescopeWhat’s going on inside the head of this nebula? Dubbed the Exposed Cranium Nebula for its similarity to the human brain, what created the nebula remains a mystery. One thought is that the Cranium Nebula, also known as PMR 1, is a planetary nebula surrounding a white dwarf star. In this mode, the outer…Read More

The Aurora TreeYes, but can your tree do this? Pictured is a visual coincidence between the dark branches of a nearby tree and bright glow of a distant aurora. The beauty of the aurora — combined with how it seemed to mimic a tree right nearby — mesmerized the photographer to such a degree that he momentarily forgot to take pictures. When…Read More

Two Eclipses of Saros 133Centered on maximum eclipse, these two total lunar eclipse sequences look almost identical. Yet the one shown on top is composed of images recorded in February 2008, while at the bottom is the recent March 2026 total eclipse of the Moon. Why are they so similar? Because these two total lunar eclipses are from the same…Read More

The Astrosphere of HD 61005Do young stars blow bubbles? The larger view shows a stellar field observed with the Cerro Tololo Inter-American Observatory in Chile, and the inset highlights HD 61005, a star like our Sun, only 120 light-years away. Much younger than the Sun, at just about 100 million years old, it blows a fast and dense stellar wind…Read More

Total Lunar Eclipse over Tsé Bit’a’írlier this week, Earth’s shadow swept across the full Moon in the year’s only total lunar eclipse. This stunning sequence combines images showing the Moon’s path across the night sky. Each lunar image captures our planet’s shadow gradually engulfing the Moon, culminating in its red glow. Sunlight scatters…Read More

Shapley 1: An Annular Planetary NebulaWhat’s looking back at you isn’t a cosmic eye, but Shapley 1, a beautifully symmetric planetary nebula. Shapley 1, also known as the Fine Ring Nebula or PLN 329+2.1, bejewels the southern sky constellation of the Carpenter’s Square (Norma). The nebula is the result of a star near the mass of our Sun run…Read More

Flying over the North Pole of MarsIf you could fly over the North Pole of Mars, what would you see?  Images from ESA’s Mars Express mission in 2019 were compiled into the featured video which shows just such a trip. First you see below you a landscape tinted orange by rusted iron in the fine soil, with some land appearing darker due to exposed ro…Read More

The Dusty Surroundings of Orion and the PleiadesHow well do you know the night sky? OK, but how well can you identify famous sky objects in a very deep image? Either way, here is a test: see if you can find some well-known night-sky icons in a deep image filled with filaments of normally faint dust and gas. This image contains the Pleiades star…Read More

The Moon During a Total Lunar EclipseHow does the Moon’s appearance change during a total lunar eclipse? The featured time-lapse video was digitally processed to keep the Moon bright and centered during the 5-hour eclipse of 2018 January 31. At first the full moon is visible because only a full moon can undergo a lunar eclipse. Stars move by in…Read More

Lunar Occultation of MercuryFans of the western sky after sunset have lately enjoyed this month’s remarkable array of bright planets. Witnessed from some locations, on February 18 planet Mercury even appeared to slide behind the Moon, an event known as a lunar occultation. These two snapshots, taken in early evening skies show before and after…Read More

Sharpless 249 and the Jellyfish NebulaNormally faint and elusive, the Jellyfish Nebula is caught in this alluring telescopic field of view. Floating in the interstellar sea, the nebula is anchored right and left by two bright stars, Mu and Eta Geminorum, at the foot of the celestial twins. The Jellyfish Nebula itself is right of center, seen as a…Read More

Webb and Hubble: IC 5332What does the universe look like through infrared goggles? Our eyes can only see visible light, but astronomers want to see more. Today’s APOD shows spiral galaxy IC 5332 as seen by two NASA telescopes: Webb in mid-infrared and Hubble in ultraviolet and visible light. To toggle between the two space-based views just slide y…Read More

The Egg Nebula from the Hubble Telescopever wonder what it would look like to crack open the Sun? The Egg Nebula, a dying Sun-like star, can unscramble this question. Pictured is a combination of several visible and infrared images of the nebula (also known as RAFGL 2688 or CRL 2688) taken with the Hubble Space Telescope. The star has shed its…Read More

Planet Parade over Sydney Opera HouseLook up this week and see a whole bunch of planets. Just after sunset, looking west (mostly), planets Mercury, Venus, Saturn, and Jupiter will all be visible to the unaided eye simultaneously. If you have a telescope, planets Uranus and Neptune can also be seen. In order up from the horizon, the lineup this…Read More

Pleiades: The Seven Sisters Star ClusterHave you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city. With a long exposure…Read More

Shadow of a Martian RobotWhat if you saw your shadow on Mars and it wasn’t human? Then you might be the Opportunity rover exploring Mars. Opportunity explored the Red Planet from 2004 to 2018, finding evidence of ancient water, and sending breathtaking images across the inner Solar System. Pictured here in 2004, Opportunity looks opposite the…Read More

Twilight with Moon and PlanetsOnly two days after the February New Moon’s annular eclipse of the Sun, a slender lunar crescent poses above the western horizon after sunset in this wintry twilight skyscape. Its nightside faintly illuminated by earthshine, the young Moon is joined by three bright planets in the mostly clear, early evening skies…Read More

B93: A Dark Interstellar Ghost”A ghost in the Milky Way…” says Christian Bertincourt, the astrophotographer behind this striking image of Barnard 93 (B93). The 93rd entry in Barnard’s Catalogue of Dark Nebulae, B93 lies within the Small Sagittarius Star Cloud (Messier 24), where its darkness stands in stark contrast to bright stars and gas in th…Read More

IC 2574: Coddington’s NebulaGrand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact, dwarf galaxy IC 2574 shows clear evidence of intense star forming activity in its telltale reddish regions of glowing…Read More

Orion’s CradleCradled in red-glowing hydrogen gas, stars are being born in Orion. These stellar nurseries lie at the edge of the giant Orion molecular cloud complex, some 1,500 light-years away. This detailed view spans about 12 degrees across the center of the well-known constellation, with the Great Orion Nebula, the closest large star-forming…Read More

Tails of Comet WierzchośSome comets are regular guests of our solar neighborhood; others come by only once, never to return. We won’t have another chance to see Comet C/2024 E1 (Wierzchoś), which is currently making its way through the inner Solar System. The hyperbolic orbit of this comet indicates that it will likely become an interstellar tra…Read More

Unexplained Shocks Around a White Dwarf StarHow is RXJ0528+2838 creating such shock waves? A recently discovered white dwarf star, the farther left of the two largest white spots, RXJ0528+2838, was found 730 light-years away from Earth. Most stars, when done fusing nuclei in their cores for energy, become red giant stars, the cores of which live…Read More

To Fly Free in SpaceWhat would it be like to fly free in space? About 100 meters from the cargo bay of a space shuttle, Bruce McCandless II was living the dream — floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. During Space Shuttle…Read More

Roses are RedRoses are red, nebulas are too, and this Valentine’s gift is a stunning view! Pictured is a loving look at the Rosette Nebula (NGC 2237): a cosmic bloom of bright young stars sitting atop a stem of glowing hot gas. The rose’s blue-white speckles are among the most luminous stars in the galaxy, with some burning millions of times b…Read More