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Point your telescope toward the high flying constellation Pegasus and you can find this cosmic expanse of Milky Way stars and distant galaxies . NGC 7814 is centered in the sharp field of view that would almost be covered by a full moon. NGC 7814 is sometimes called the Little Sombrero for its resemblance to the brighter more famous M104, the Sombrero Galaxy . Both Sombrero and Little Sombrero are spiral galaxies seen edge-on, and both have extensive halos and central bulges cut by a thin disk with thinner dust lanes in silhouette. In fact , NGC 7814 is some 40 million light-years away and an estimated 60,000 light-years across. That actually makes the Little Sombrero about the same physical size as its better known namesake, appearing smaller and fainter only because it is farther away. from NASA https://ift.tt/bd7PH0L

The North America nebula on the sky can do what the North America continent on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent, the bright part that appears as the east coast is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall . The featured image shows the star forming wall lit and eroded by bright young stars and partly hidden by the dark dust they have created. The part of the North America nebula (NGC 7000) shown spans about 50 light years and lies about 1,500 light years away toward the constellation of the Swan ( Cygnus ). from NASA https://ift.tt/eImqlno

What's that in the sky? Above the city, above most clouds, far in the distance: it's a comet. Pictured , the impressive tail of Comet C/2024 G3 (ATLAS) was imaged from Brasília , Brazil four days ago. Last week the evolving comet rounded the Sun well inside the orbit of planet Mercury, going so close there was early concern that it might break up -- and recent evidence that it really did. At one point near perihelion, Comet ATLAS was so bright that sightings were even reported during the day -- over the bright sky near the Sun -- by careful observers . Over the past few days, Comet ATLAS has developed a long tail that has been partly visible with unaided eyes after sunset, most notably in Earth's southern hemisphere . from NASA https://ift.tt/c3xslPI

Why does Comet ATLAS have such colorful tails? Last week Comet C/2024 G3 (ATLAS) passed its closest to the Sun -- well inside the orbit of Mercury -- and brightened dramatically . Unfortunately, the comet was then so angularly near the Sun that it was very hard for human s to see. But NASA's SOHO spacecraft saw it. Pictured is a SOHO ( LASCO C3) image of Comet ATLAS that is a composite of several different color filters. Of the several tails visible, the central white tails are likely made of dust and just reflecting back sunlight. The red, blue, and green tails are likely ion tails with their colors dominated by light emitted by specific gases that were ejected from the comet and energized by the Sun. Currently, Comet ATLAS is showing long tails in southern skies but fading as it moves out of the inner Solar System . from NASA https://ift.tt/ulKMhwt

What would it look like to land on Saturn's moon Titan? The European Space Agency 's Huygens probe set down on the Solar System's cloudiest moon in 2005, and a time-lapse video of its descent images was created. Huygens separated from the robotic Cassini spacecraft soon after it achieved orbit around Saturn in late 2004 and began approaching Titan . For two hours after arriving, Huygens plummeted toward Titan 's surface, recording at first only the shrouded moon's opaque atmosphere. The computerized truck-tire sized probe soon deployed a parachute to slow its descent, pierced the thick clouds, and began transmitting images of a strange surface far below never before seen in visible light . Landing in a dried sea and surviving for 90 minutes, Huygen's returned unique images of a strange plain of dark sandy soil strewn with smooth, bright, fist-sized rocks of ice. from NASA https://ift.tt/QpLBuHj

On January 13 a Full Moon and a Full Mars were close, both bright and opposite the Sun in planet Earth's sky. In fact Mars was occulted, passing behind the Moon, when viewed from some locations in North America and northwest Africa. As seen from Richmond, Virginia, USA, this composite image sequence follows the evening lunar occultation before, during, and after the much anticipated celestial spectacle . The telescopic time series is constructed from an exposure made every two minutes while tracking the Moon over the hours encompassing the event. As a result, the Red Planet's trajectory seems to follow a gently curved path due to the Moon's slightly different rate of apparent motion. The next lunar occultation of bright planet Mars will be on February 9 when the moon is in a waxing gibbous phase. Lunar occultations are only ever visible from a fraction of the Earth's surface, though. The February 9 occultation of Mars will be seen from parts of Russia, China, easte...

Massive stars in our Milky Way Galaxy live spectacular lives. Collapsing from vast cosmic clouds, their nuclear furnaces ignite and create heavy elements in their cores. After only a few million years for the most massive stars, the enriched material is blasted back into interstellar space where star formation can begin anew. The expanding debris cloud known as Cassiopeia A is an example of this final phase of the stellar life cycle . Light from the supernova explosion that created this remnant would have been first seen in planet Earth's sky about 350 years ago, although it took that light 11,000 years to reach us. This sharp NIRCam image from the James Webb Space Telescope shows the still hot filaments and knots in the supernova remnant. The whitish, smoke-like outer shell of the expanding blast wave is about 20 light-years across. A series of light echoes from the massive star's cataclysmic explosion are also identified in Webb's detailed images of the surrounding ...

Beautiful and bright spiral galaxy M83 lies a some twelve million light-years away, near the southeastern tip of the very long constellation Hydra . Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its popular name, The Southern Pinwheel. Still, reddish star forming regions that dot this cosmic pinwheel's spiral arms have suggested another nickname, the Thousand-Ruby Galaxy . A mere 40,000 light-years across, smaller than the Milky Way, M83 is a member of a group of galaxies that includes active galaxy Centaurus A . In fact, the core of M83 itself is bright at x-ray energies , showing a high concentration of neutron stars and black holes left from an intense burst of star formation. This sharp color image also features spiky foreground Milky Way stars and distant background galaxies. The image data was captured with the Dark Energy Camera and Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory. from NASA https://ift.tt/V...

Does the Moon ever engulf Mars? Yes, but only in the sense that it moves in front, which happens on rare occasions . This happened just yesterday, though, as seen from some locations in North America and western Africa . This occultation was notable not only because the Moon was a fully lit Wolf Moon , but because Mars was near its largest and brightest, moving to opposition -- the closest to the Earth in its orbit -- only tomorrow. The engulfing , more formally called an occultation , typically lasting about an hour. The featured image was taken from near Chicago , Illinois , USA just as Earth's largest satellite was angularly moving away from the much more distant red planet . Our Moon occasionally moves in front of all of the Solar System 's planets. Given the temporary alignment of orbital planes , the next time our Moon eclipses Mars will be a relatively soon February 9. from NASA https://ift.tt/bKLuCMO

Why is Polaris called the North Star? First, Polaris is the nearest bright star toward the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to revolve around Polaris , but Polaris itself always stays in the same northerly direction -- making it the North Star . Since no bright star is near the south spin axis of the Earth, there is currently no bright South Star . Thousands of years ago, Earth's spin axis pointed in a slightly different direction so that Vega was the North Star . Although Polaris is not the brightest star on the sky, it is easily located because it is nearly aligned with two stars in the cup of the Big Dipper . Polaris is near the center of the five-degree wide featured image, a digital composite of hundreds of exposures that brings out faint gas and dust of the Integrated Flux Nebula (IFN) all over the frame. The surface of Cepheid Polaris slowly pulsates , causing the famous star to change its brightness by a few percent over...

Comet ATLAS is really bright now, but also really close to the Sun. Outside the glow of the Sun, Comet C/2024 G3 (ATLAS) would be one of the more remarkable comet sights of recent years, reflecting about as much sunlight to Earth as Comet Tsuchinshan-ATLAS did in October, and now rivaling even planet Venus . But the giant snowball is now so close to the Sun that it can only be seen through the light of the early morning dawn or the early evening dusk. Today, Comet ATLAS is at perihelion -- its closest ever to the Sun. Although the future brightness of comets is notoriously hard to predict, there is hope that Comet ATLAS will survive its close pass near the Sun and remain bright enough to be seen with the unaided eye over the next few days -- and possibly a good camera comet for weeks. The featured image was taken early yesterday morning near Tornaľa , Slovakia . from NASA https://ift.tt/GhF8Aw5

Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn 's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely. The huge crater, named Herschel after the 1789 discoverer of Mimas, Sir William Herschel , spans about 130 kilometers and is featured here . Mimas ' low mass produces a surface gravity just strong enough to create a spherical body but weak enough to allow such relatively large surface features. Mimas is made of mostly water ice with a smattering of rock - so it is accurately described as a big dirty snowball. The featured image was taken during the closest-ever flyby of the robot spacecraft Cassini past Mimas in 2010 while in orbit around Saturn . from NASA https://ift.tt/0367cUF

Only Mercury is missing from a Solar System parade of planets in this early evening skyscape . Rising nearly opposite the Sun, bright Mars is at the far left. The other naked-eye planets Jupiter, Saturn, and Venus, can also be spotted, with the the position of too-faint Uranus and Neptune marked near the arcing trace of the ecliptic plane . On the far right and close to the western horizon after sunset is a young crescent Moon whose surface is partly illuminated by earthshine. In the foreground of the composite panorama captured on 2 January, planet Earth is represented by Mount Etna's lower Silvestri Crater . Of course Earth's early evening skies are full of planets for the entire month of January . On 13 January, a nearly Full Moon will appear to pass in front of Mars for skywatchers in the continental U.S. and Eastern Canada. from NASA https://ift.tt/sX4p0nx

An unassuming region in the constellation Taurus holds these dark and dusty nebulae. Scattered through the scene, stars in multiple star systems are forming within their natal Taurus molecular cloud complex some 450 light-years away. Millions of years young and still going through stellar adolescence, the stars are variable in brightness and in the late phases of their gravitational collapse. Known as T-Tauri class stars they tend to be faint and take on a yellowish hue in the image. One of the brightest T-Tauri stars in Taurus, V773 (aka HD283447) is near the center of the telescopic frame that spans over 1 degree. Toward the top is the dense, dark marking on the sky cataloged as Barnard 209. from NASA https://ift.tt/KSyBuGD

The colorful, spiky stars are in the foreground of this image taken with a small telescope on planet Earth . They lie well within our own Milky Way Galaxy . But the two eye-catching galaxies in the frame lie far beyond the Milky Way, at a distance of over 300 million light-years. The galaxies' twisted and distorted appearance is due to mutual gravitational tides as the pair engage in close encounters. Cataloged as Arp 273 (also as UGC 1810 ), these galaxies do look peculiar , but interacting galaxies are now understood to be common in the universe. Closer to home, the large spiral Andromeda Galaxy is known to be some 2 million light-years away and inexorably approaching the Milky Way. In fact the far away peculiar galaxies of Arp 273 may offer an analog of the far future encounter of Andromeda and Milky Way. Repeated galaxy encounters on a cosmic timescale ultimately result in a merger into a single galaxy of stars. From our perspective , the bright cores of the Arp 273 galaxies...

What happens after a star explodes? A huge fireball of hot gas shoots out in all directions. When this gas slams into the existing interstellar medium , it heats up so much it glows. Two different supernova remnant s (SNRs) are visible in the featured image, taken at the Oukaïmeden Observatory in Morocco . The blue soccer ball -looking nebula toward the upper left is SNR G179.0+02.6 , which appears to be the smaller one. This supernova , about 11,000 light years distant, detonated about 50,000 years ago. Although composed mostly of hydrogen gas, the blue light is emitted by a trace amount of oxygen . The seemingly larger SNR, dominating the lower right of the frame, is the Spaghetti Nebula, cataloged as Simeis 147 and sh2-240. This supernova, only about 3,000 light years away, exploded about 40,000 years ago. Comparatively, even though they appear different sizes , both supernova remnants are not only roughly the same age, but about the same size, too. from NASA https://ift.tt/...

It was a new year, and the sky was doubly red. The new year meant that the Earth had returned to its usual place in its orbit on January 1, a place a few days before its closest approach to the Sun . The first of the two red skyglows, on the left, was a red aurora , complete with vertical rays , caused by a blast from the Sun pushing charged particles into Earth's atmosphere. The second red glow, most prominent on the far right, was possibly a SAR arc caused by a river of charged particles flowing across Earth's atmosphere . Although both appear red, the slight color difference is likely due to the aurora being emitted by both oxygen and nitrogen, whereas the higher SAR arc was possibly emitted more purely by atmospheric oxygen. The featured image was taken on January 1 from near Pieve di Cadore in Italy . from NASA https://ift.tt/ZBsWGdi

Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas , lanes of dark dust , bursts of star formation , and streams of cast-away stars . The featured image in scientifically assigned colors is a composite of Hubble exposures in visible light and Webb exposures in infrared light. Astronomers predict that NGC 2207, the larger galaxy on the right, will eventually incorporate IC 2163, the smaller galaxy on the left. In the most recent encounter that about peaked 40 million years ago, the smaller galaxy is swinging around counter-clockwise and is now slightly behind the larger galaxy. The space between stars is so vast that when galaxies collide , the stars in them usually do not collide. from NASA https://ift.tt/zuPLMiN

Have you ever seen a rocket launch -- from space? A close inspection of the featured time-lapse video will reveal a rocket rising to Earth orbit as seen from the International Space Station (ISS). The Russia n Soyuz-FG rocket was launched in November 2018 from the Baikonur Cosmodrome in Kazakhstan , carrying a Progress MS-10 (also 71P ) module to bring needed supplies to the ISS. Highlights in the 90-second video (condensing about 15-minutes) include city lights and clouds visible on the Earth on the lower left, blue and gold bands of atmospheric airglow running diagonally across the center, and distant stars on the upper right that set behind the Earth. A lower stage can be seen falling back to Earth as the robotic supply ship fires its thrusters and begins to close on the ISS , a space laboratory that celebrated its 25th anniversary in 2023. Astronauts who live aboard the Earth-orbiting ISS conduct, among more practical duties, numerous science experiments that expand ...

Earth's orbit around the Sun is not a circle, it's an ellipse. The point along its elliptical orbit where our fair planet is closest to the Sun is called perihelion. This year perihelion is today, January 4, at 13:28 UTC, with the Earth about 147 million kilometers from the Sun. For comparison , at aphelion on last July 3 Earth was at its farthest distance from the Sun, some 152 million kilometers away. But distance from the Sun doesn't determine Earth's seasons. It's only by coincidence that the beginning of southern summer (northern winter) on the December solstice - when this H-alpha picture of the active Sun was taken - is within 14 days of Earth's perihelion date. And it's only by coincidence that Earth's perihelion date is within 11 days of the historic perihelion of NASA's Parker Solar Probe . Launched in 2018, the Parker Solar Probe flew within 6.2 million kilometers of the Sun's surface on 2024 December 24, breaking its own record fo...