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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. from NASA https://ift.tt/DwaxEc6
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 ...
Even 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 . from NASA https://ift.tt/vmlbN7Y
A 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 angular size of the full moon, Cygnus sets the sky afire with active star formation where clouds of gas and dust collapse under gravity until nuclear fusion ignites and new stars are born. These stars ionize the surrounding hydrogen gas, causing it to glow crimson , while tendrils of interstellar dust absorb some of that light and cast dark shadows across the sky. Cygnus is a trove of celestial treasures, notably the Veil , Crescent , and Pelican nebulae, as well as Cygnus X-1 , the first confirmed black hole . Cygnus continues to yield fresh science, including a new three-dimensional model of the Cygnus Loop made possible by the Chandra X-ray Observatory . f...
This 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 interstellar pond of gas and dust. the Tadpoles of IC 410. Partly obscured by foreground dust, the nebula itself surrounds NGC 1893, a young galactic cluster of stars. Formed in the interstellar cloud a mere 4 million years ago, the intensely hot, bright cluster stars energize the glowing gas. But the cosmic tadpoles themselves are composed of denser cooler gas and dust. Around 10 light-years long they are likely sites of ongoing star formation . Sculpted by stellar winds and radiation their heads are outlined by bright ridges of ionized gas while their tails trail away from the cluster's central young stars. IC 410 lies some 10,000 light-years away, toward th...
To 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 slithering viper . Also known as the Temple of Kukulkan , the impressive step-pyramid stands 30 meters tall and 55 meters wide at the base. Built up as a series of square terraces by the pre-Columbian civilization between the 9th and 12th century, the structure can be used as a calendar and is noted for astronomical alignments . The featured composite image was captured in 2019 with Jupiter and Saturn straddling the diagonal central band of our Milky Way galaxy . In a few days another equinox will occur -- not only at Temple of Kukulcán, but all over planet Earth . from NASA https://ift.tt/E2wnAdr
Want 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. K2-315b's measured orbital period in days is nearly equal to the extremely popular irrational number Pi. That puts the exoplanet so close to its parent star that its surface is likely very warm, baking-hot in fact . And this Pi planet is over 185 light-years away. So instead of trying to arrange for an interstellar vacation to K2-315b, there may be easier and more comfortable ways for you to celebrate Pi day on planet Earth . from NASA https://ift.tt/uFCQ2Mn
In 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 trail of the reddened Moon in the eclipse-darkened skies above the lake and trees. Of course, the apparent motion of Moon and stars revealed in the timelapse composite reflect the Earth's daily rotation around its axis . Dramatically punctuating the Moon's trail as totality ended, a single, separate telephoto image of the totally eclipsed Moon was scaled and blended into the scene. from NASA https://ift.tt/AbQgh8n
Is 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 brought together by gravity to create stars . The shape of CG 4 resembles that of a comet , but its head is 1.5 light-year in diameter and its tail is 8 light-years long; for comparison, the distance from the Earth to the sun is only 8 light-minutes . Astronomers believe that the tail of a cometary globule could have been shaped by a nearby supernova explosion or by irradiation from hot, massive stars. Indeed, CG 4 and other nearby globules point away from the Vela Supernova Remnant , at the center of the Gum Nebula . The edge-on spiral galaxy , ESO 257-19, is more than a hundred million light-years beyond CG 4, and is completely safe from the “ monster ”. from NA...
Are 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, but in other directions, no bright star exists. In these directions, astronomers can create an artificial star with a laser . Subsequent observations of the artificial laser guide star can reveal information so detailed about the changing blurring effects of the Earth's atmosphere that much of it can be removed by rapidly flexing a telescope's mirror. Such adaptive optics techniques allow high-resolution ground-based observations of real star s, planets , and nebulas . Pictured here , telescopes at Paranal Observatory in Chile study a colorful sky filled with green airglow and the Magellanic Clouds on the left, red airglow on the right, and the majestic cent...
Yes, 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 viewed at the right angle , it seemed that this tree had aurora for leaves. Fortunately, before the aurora morphed into a different overall shape , he came to his senses and captured the awe-inspiring momentary coincidence . Typically triggered by solar explosions , aurora are caused by high energy electrons impacting the Earth's atmosphere around 150 kilometers up. The unusual Earth-sky collaboration was witnessed in March of 2017 in Iceland . from NASA https://ift.tt/xXbMjfW
Centered 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 Saros cycle. The Saros cycle was discovered historically from observations of the Moon's orbit. With a period of 18 years, 11 and 1/3 days, the cycle predicts when the Sun, Earth, and Moon all return to the same relative geometry for a lunar ( or solar ) eclipse. Eclipses separated by one Saros period belong to the same numbered Saros series, in this case Saros 133. So expect the next lunar eclipse in Saros 133 to be a repeat of this year's March 3 eclipse. You can watch the next Saros 133 total lunar eclipse on March 13, 2044 . from NASA https://ift.tt/r0nNI4G
Do 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 that pushes out the cooler dust and gas that surrounds it, forming a bubble called an astrosphere . The star-blown bubble was detected with the Chandra X-ray Observatory , and it has a diameter roughly 200 times the Earth-Sun distance . Our Sun has a bubble too, called the heliosphere , which protects the planets from cosmic radiation . Also shown in the inset is debris left behind from star formation, observed by Hubble . The debris appears as wings , giving the star its nickname: the Moth . from NASA https://ift.tt/b5vghaU
Earlier 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 and refracts as it passes through Earth’s atmosphere toward the Moon. Shorter wavelength light (blue and green) scatters more efficiently , leaving red, orange, and yellow hues to paint the lunar surface. Tsé Bit'a'í (”rock with wings”, also known as Shiprock), located in Navajo Nation , provides a powerful volcanic foreground central to this photo and to stories of Navajo origin, adventure, and heroism . As the first full moon of the lunar new year , this eclipse held significance across cultures. Visible from East Asia to North America , this eclipse united observers across great distances, a cosmic reminder that we share the same sky. from NASA https://ift.tt/hjK...
What’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 running out of fuel and shedding its outer layers . Glowing oxygen from those expelled layers makes up the circular halo. The bright central point is actually a binary: a white dwarf , the remaining stellar core after the outer layers are expelled into space, and another star, orbiting each other every 2.9 days. Shapley 1’s annular shape is due to our top-down view of the system and provides insight into the influence of central stars on planetary nebula structures . from NASA https://ift.tt/vDaNb8X
How 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 cluster , Barnard's Loop , Orion Nebula , Aldebaran , Betelgeuse , Witch Head Nebula , Eridanus Loop , and the California Nebula . To find their real locations, here is an annotated image version . The reason this task might be difficult is similar to the reason it is initially hard to identify familiar constellations in a very dark sky : the tapestry of our night sky has an extremely deep hidden complexity . The featured composite reveals some of this complexity in a 16 hours of sky exposure in dark skies over Granada , Spain . from NASA https://ift.tt/d0wK8Hx

Lunar Occultation of Mercury

Fans 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 telescopic views of the rare disappearance of innermost planet behind young Moon. The top panel finds bright Mercury just visible at the northern (right) edge of the earthshine-illuminated lunar disk. In the bottom panel the bright planet has emerged in darker skies beyond the Moon's sunlit crescent. As seen south of Sallisaw, Oklahoma, planet Earth, this lunar occultation of Mercury lasted only about 3 minutes ( video ). But you can still check out a parade of planets tonight . from NASA https://ift.tt/Mkel3r9

Sharpless 249 and the Jellyfish Nebula

Normally 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 brighter arcing ridge of emission with dangling tentacles. In fact, this cosmic jellyfish is part of bubble-shaped supernova remnant IC 443 , the expanding debris cloud from a massive star that exploded . Light from the explosion first reached planet Earth over 30,000 years ago. Like its cousin in astrophysical waters the Crab Nebula supernova remnant, the Jellyfish Nebula is known to harbor a neutron star, the ultradense remnant of the collapsed stellar core. An emission nebula cataloged as Sharpless 249 fills the field at the upper left. The Jellyfish Nebula is about 5,000 light-years away. At that distance, this image would be about 300 light-years across. from NASA...

Webb and Hubble: IC 5332

What 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 your cursor over the image (or follow this link ). The Hubble image highlights the spiral arms of the galaxy separated by dark regions, whereas the Webb image reveals a finer, more tangled structure. Interstellar dust scatters and absorbs light from the stars in the galaxy, causing the dark dust lanes in the Hubble image, and then emits heat in infrared light, so dust glows in this Webb image. The Mid-InfraRed Instrument on Webb needs to operate at a chilling temperature of -266ºC (or - 447ºF), otherwise it would detect infrared radiation from the telescope itself. Combining these observations, astronomers connect the “small scale” of gas and stars t...
Ever 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 outer layers, and a bright, hot core (or "yolk") now illuminates the milky "egg white" shells of gas and dust surrounding the center. The central lobes and rings are structures of gas and dust recently ejected into space, with the dust being dense enough to block our view of the stellar core . Light beams emanate from that blocked core , escaping through holes carved in the older ejected material by newer, faster jets expelled from the star’s poles . Astronomers are still trying to figure out what causes the disks, lobes, and jets during this short (only a few thousand years!) phase of the star’s evolution , making this an egg-cellent image to study! ...