Alpha News

The core of the Milky Way is rising beyond the Chilean mountain-top La Silla Observatory in this deep night skyscape . Seen toward the constellation Sagittarius, our home galaxy's center is flanked on the left, by the European Southern Observatory's New Technology Telescope which pioneered the use of active optics to accurately control the shape of large telescope mirrors. To the right stands the ESO 3.6-meter Telescope, home of the exoplanet hunting HARPS and NIRPS spectrographs. Between them, the galaxy's central bulge is filled with obscuring clouds of interstellar dust, bright stars, clusters, and nebulae . Prominent reddish hydrogen emission from the star-forming Lagoon Nebula, M8, is near center. The Trifid Nebula, M20, combines blue light of a dusty reflection nebula with reddish emission just left of the cosmic Lagoon. Both are popular stops on telescopic tours of the galactic center. The composited image is a stack of separate exposures for ground and sky m...

On flight day 13 (November 28, 2022) of the Artemis I mission, the Orion spacecraft reached its maximum distance from its home world. Over 430,000 kilometers from Earth in a distant retrograde orbit, Orion surpassed the record for most distant spacecraft designed to carry humans. That record was previously set in 1970 during the Apollo 13 mission to the Moon. Both Earth and Moon are in the same field of view in this video frame from Orion on Artemis I mission flight day 13. The planet and its large natural satellite even appear about the same apparent size from the uncrewed spacecraft's perspective . from NASA https://ift.tt/gFxozey

Could there be a tornado inside another tornado? In general, no. OK, but could there be a tornado inside a wider dust devil ? No again, for one reason because tornados comes down from the sky, but dust devils rise up from the ground. What is pictured is a landspout , an unusual type of tornado known to occur on the edge of a violent thunderstorm . The featured landspout was imaged and identified in Kansas , USA , in June 2019 by an experienced storm chaser. The real tornado is in the center, and the outer sheath was possibly created by large dust particles thrown out from the central tornado. So far, the only planet known to create tornados is Earth , although tornado-like activity has been found on the Sun and dust devils are common on Mars . from NASA https://ift.tt/0LObG6l

What does the largest moon in the Solar System look like? Jupiter 's moon Ganymede , larger than even Mercury and Pluto , has an icy surface speckled with bright young craters overlying a mixture of older, darker, more cratered terrain laced with grooves and ridges. The cause of the grooved terrain remains a topic of research , with a leading hypothesis relating it to shifting ice plates. Ganymede is thought to have an ocean layer that contains more water than Earth -- and might contain life . Like Earth's Moon , Ganymede keeps the same face towards its central planet, in this case Jupiter. The featured image was captured in 2021 by NASA's robotic Juno spacecraft when it passed by the immense moon. The close pass reduced Juno's orbital period around Jupiter from 53 days to 43 days. Juno continues to study the giant planet 's high gravity, unusual magnetic field , and complex cloud structures . from NASA https://ift.tt/Ta7R4e3

This eagle ray glides across a cosmic sea. Officially cataloged as SH2-63 and LBN 86 , the dark nebula is composed of gas and dust that just happens to appear shaped like a common ocean fish . The interstellar dust nebula appears light brown as it blocks and reddens visible light emitted behind it. Dark nebulas glow primarily in infrared light , but also reflect visible light from surrounding stars. The dust in dark nebulas is usually sub-millimeter chunks of carbon, silicon, and oxygen , frequently coated with frozen carbon monoxide and nitrogen . Dark nebulas are also known as molecular clouds because they also contain relatively high amounts of molecular hydrogen and larger molecules . Previously unnamed, the here dubbed Eagle Ray Nebula is normally quite dim but has been imaged clearly over 20-hours through dark skies in Chile . from NASA https://ift.tt/aDhVEWP

Where do comet tails come from? There are no obvious places on the nuclei of comets from which the jets that create comet tails emanate. In 2016, though, ESA's Rosetta spacecraft not only imaged a jet emerging from Comet 67P/Churyumov-Gerasimenko , but flew right through it. Featured is a telling picture showing a bright plume emerging from a small circular dip bounded on one side by a 10-meter high wall. Analyses of Rosetta data show that the jet was composed of both dust and water-ice. The rugged but otherwise unremarkable terrain indicates that something likely happened far under the porous surface to create the plume. This image was taken about two months before Rosetta's mission ended with a controlled impact onto Comet 67P's surface. from NASA https://ift.tt/1P0gFeN

Immersed in an eerie greenish light, this rugged little planet appears to be home to stunning water falls and an impossibly tall mountain. It's planet Earth of course. On the night of November 9 the nadir-centered 360 degree mosaic was captured by digital camera from the Kirkjufell mountain area of western Iceland. Curtains of shimmering Aurora Borealis or Northern Lights provide the pale greenish illumination. The intense auroral display was caused by solar activity that rocked Earth's magnetosphere in early November and produced strong geomagnetic storms. Kirkjufell mountain itself stands at the top of the stereographic projection's circular horizon. Northern hemisphere skygazers will recognize the familiar stars of the Big Dipper just above Kirkjufell's peak. At lower right the compact Pleiades star cluster and truly giant planet Jupiter also shine in this little planet's night sky. from NASA https://ift.tt/krWtsv4

Jupiter looks sharp in these two rooftop telescope images . Both were captured on November 17 from Singapore, planet Earth, about two weeks after Jupiter's 2023 opposition . Climbing high in midnight skies the giant planet was a mere 33.4 light-minutes from Singapore. That's about 4 astronomical units away. Jupiter's planet girdling dark belts and light zones are visible in remarkable detail, along with the giant world's whitish oval vortices. Its signature Great Red Spot is still prominent in the south. Jupiter rotates rapidly on its axis once every 10 hours. So, based on video frames taken only 15 minutes apart, these images form a stereo pair. Look at the center of the pair and cross your eyes until the separate images come together to see the Solar System's ruling gas giant in 3D. from NASA https://ift.tt/uQS0sqd

The cosmic brush of star formation composed this interstellar canvas of emission, dust, and dark nebulae. A 5 degree wide telescopic mosaic, it frames a region found north of bright star Aldebaran on the sky, at an inner wall of the local bubble along the Taurus molecular cloud . At lower left, emission cataloged as Sh2-239 shows signs of embedded young stellar objects. The region's Herbig-Haro objects, nebulosities associated with newly born stars, are marked by tell-tale reddish jets of shocked hydrogen gas. Above and right T Tauri, the prototype of the class of T Tauri variable stars , is next to a yellowish nebula historically known as Hind's Variable Nebula ( NGC 1555 ). T Tauri stars are now generally recognized as young, less than a few million years old, sun-like stars still in the early stages of formation . from NASA https://ift.tt/itoQ1Yf

Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant in the long-necked, northern constellation Camelopardalis . A sprawling island universe , IC 342 would otherwise be a prominent galaxy in our night sky, but it is hidden from clear view and only glimpsed through the veil of stars, gas and dust clouds along the plane of our own Milky Way galaxy . Even though IC 342's light is dimmed and reddened by intervening cosmic clouds , this sharp telescopic image traces the galaxy's own obscuring dust, young star clusters, and glowing star forming regions along spiral arms that wind far from the galaxy's core . IC 342 has undergone a recent burst of star formation activity and is close enough to have gravitationally influenced the evolution of the local group of galaxies and the Milky Way. from NASA https://ift.tt/DWkZMJQ

These chaotic and tangled filaments of shocked, glowing gas are spread across planet Earth's sky toward the constellation of Cygnus as part of the Veil Nebula . The Veil Nebula itself is a large supernova remnant , an expanding cloud born of the death explosion of a massive star. Light from the original supernova explosion likely reached Earth over 5,000 years ago. The glowing filaments are really more like long ripples in a sheet seen almost edge on, remarkably well separated into the glow of ionized hydrogen atoms shown in red and oxygen in blue hues. Also known as the Cygnus Loop and cataloged as NGC 6979 , the Veil Nebula now spans about 6 times the diameter of the full Moon . The length of the wisp corresponds to about 30 light years , given its estimated distance of 2,400 light years. Often identified as Pickering's Triangle for a director of Harvard College Observatory , it is perhaps better named for its discoverer, astronomer Williamina Fleming , as Fleming's ...

Sculpted by stellar winds and radiation, a magnificent interstellar dust cloud by chance has assumed this recognizable shape . Fittingly named the Horsehead Nebula , it is some 1,500 light-years distant , embedded in the vast Orion cloud complex. About five light-years "tall," the dark cloud is cataloged as Barnard 33 and is visible only because its obscuring dust is silhouetted against the glowing red emission nebula IC 434. Stars are forming within the dark cloud. Contrasting blue reflection nebula NGC 2023, surrounding a hot, young star , is at the lower left of the full image . The featured gorgeous color image combines both narrowband and broadband images recorded using several different telescopes. from NASA https://ift.tt/owCslH7

That's no sunspot. It's the International Space Station (ISS) caught passing in front of the Sun. Sunspot s, individually, have a dark central umbra , a lighter surrounding penumbra , and no Dragon capsules attached . By contrast, the ISS is a complex and multi-spired mechanism, one of the largest and most complicated spacecraft ever created by humanity . Also, sunspots circle the Sun , whereas the ISS orbits the Earth . Transiting the Sun is not very unusual for the ISS , which orbits the Earth about every 90 minutes, but getting one's location, timing and equipment just right for a great image is rare. The featured picture combined three images all taken in 2021 from the same location and at nearly the same time. One image -- overexposed -- captured the faint prominence s seen across the top of the Sun, a second image -- underexposed -- captured the complex texture of the Sun's chromosphere , while the third image -- the hardest to get -- captured the space s...

One year ago a Space Launch System rocket left planet Earth on November 16, 2022 at 1:47am EST carrying the Orion spacecraft on the Artemis I mission, the first integrated test of NASA’s deep space exploration systems. Over an hour after liftoff from Kennedy Space Center's historic Launch Complex 39B, one of Orion's external video cameras captured this view of its new perspective from space . In the foreground are Orion's Orbital Maneuvering System engine and auxillary engines, at the bottom of the European Service Module. Beyond one of the module's 7-meter long extended solar array wings lies the spacecraft's beautiful home world. Making close flybys of the lunar surface and reaching a retrograde orbit 70,000 kilometers beyond the Moon, the uncrewed Artemis I mission lasted over 25 days, testing capabilities to enable human exploration of the Moon and Mars. Building on the success of Artemis I , no earlier than November 2024 the Artemis II mission with a...

Light pollution is usually not a problem in Qeqertaq . In western Greenland the remote coastal village boasted a population of 114 in 2020. Lights still shine in its dark skies though. During planet Earth's recent intense geomagnetic storm, on November 6 these beautiful curtains of aurora borealis fell over the arctic realm . On the eve of the coming weeks of polar night at 70 degrees north latitude, the inspiring display of northern lights is reflected in the waters of Disko Bay. In this view from the isolated settlement a lone iceberg is illuminated by shore lights as it drifts across the icy sea . from NASA https://ift.tt/EM9G7z6

Venus now appears as Earth's brilliant morning star, shining above the southeastern horizon before dawn. For early morning risers, the silvery celestial beacon rose predawn in a close pairing with a waning crescent Moon on Thursday, November 9. But from some northern locations , the Moon was seen to occult or pass in front of Venus. From much of Europe, the lunar occultation could be viewed in daylight skies . This time series composite follows the daytime approach of Moon and morning star in blue skies from Warsaw, Poland. The progression of eight sharp telescopic snapshots , made between 10:56am and 10:58am local time, runs from left to right, when Venus winked out behind the bright lunar limb . from NASA https://ift.tt/lo7qIYa

Cataloged as M1, the Crab Nebula is the first on Charles Messier's famous list of things which are not comets . In fact, the Crab Nebula is now known to be a supernova remnant, an expanding cloud of debris from the death explosion of a massive star. The violent birth of the Crab was witnessed by astronomers in the year 1054. Roughly 10 light-years across , the nebula is still expanding at a rate of about 1,500 kilometers per second. You can see the expansion by comparing these sharp images from the Hubble Space Telescope and James Webb Space Telescope. The Crab's dynamic, fragmented filaments were captured in visible light by Hubble in 2005 and Webb in infrared light in 2023. This cosmic crustacean lies about 6,500 light-years away in the constellation Taurus . from NASA https://ift.tt/emcQW7N

In the fading darkness before dawn, a tilted triangle appeared to balance atop a rock formation off the southern tip of Sicily . Making up the points of the triangle are three of the four brightest objects visible in Earth’s sky: Jupiter , Venus and the Moon . Though a thin waning crescent , most of the moon’s disk is visible due to earthshine . Captured in this image on 2022 April 27, Venus (center) and Jupiter (left) are roughly three degrees apart -- and were headed toward a close conjunction . Conjunction s of Venus and Jupiter occur about once a year and are visible either in the east before sunrise or in the west after sunset. The featured image was taken about an hour before the arrival of the brightest object in Earth’s sky – the Sun . from NASA https://ift.tt/iaHYFNj

Have you ever seen the Andromeda galaxy? Although M31 appears as a faint and fuzzy blob to the unaided eye, the light you see will be over two million years old, making it likely the oldest light you ever will see directly . The featured image captured Andromeda just before it set behind the Swiss Alps early last year. As cool as it may be to see this neighboring galaxy to our Milky Way with your own eyes, long duration camera exposures can pick up many faint and breathtaking details . The image is composite of foreground and background images taken consecutively with the same camera and from the same location. Recent data indicate that our Milky Way Galaxy will collide and coalesce with Andromeda galaxy in a few billion years. from NASA https://ift.tt/Z1JGfLS

This is a gibbous Moon. More Earthlings are familiar with a full moon, when the entire face of Luna is lit by the Sun , and a crescent moon , when only a sliver of the Moon's face is lit. When more than half of the Moon is illuminated, though, but still short of full illumination, the phase is called gibbous . Rarely seen in television and movies, gibbous moon s are quite common in the actual night sky. The featured image was taken in Jämtland , Sweden near the end of 2018 October. That gibbous moon turned, in a few days, into a crescent moon, and then a new moon , then back to a crescent, and a few days past that, back to gibbous. Setting up to capture a picturesque gibbous moonscape, the photographer was quite surprised to find an airplane, surely well in the foreground, appearing to fly past it. from NASA https://ift.tt/VsgzoLb

This broad, luminous red arc was a surprising visitor to partly cloudy evening skies over northern France. Captured extending toward the zenith in a west-to-east mosaic of images from November 5, the faint atmospheric ribbon of light is an example of a Stable Auroral Red (SAR) arc. The rare night sky phenomenon was also spotted at unusually low latitudes around world, along with more dynamic auroral displays during an intense geomagnetic storm . SAR arcs and their relation to auroral emission have been explored by citizen science and satellite investigations. From altitudes substantially above the normal auroral glow, the deep red SAR emission is thought to be caused by strong heating due to currents flowing in planet Earth's inner magnetosphere . Beyond this SAR, the Milky Way arcs above the cloud banks along the horizon , a regular visitor to night skies over northern France. from NASA https://ift.tt/R7frN4n

Dominated by dark matter , massive cluster of galaxies Abell 2744 is known to some as Pandora's Cluster . It lies 3.5 billion light-years away toward the constellation Sculptor. Using the galaxy cluster's enormous mass as a gravitational lens to warp spacetime and magnify even more distant objects directly behind it, astronomers have found a background galaxy, UHZ1, at a remarkable redshift of Z=10.1 . That puts UHZ1 far beyond Abell 2744, at a distance of 13.2 billion light-years, seen when our universe was about 3 percent of its current age. UHZ1 is identified in the insets of this composited image combining X-rays (purple hues) from the spacebased Chandra X-ray Observatory and infrared light from the James Webb Space Telescope. The X-ray emission from UHZ1 detected in the Chandra data is the telltale signature of a growing supermassive black hole at the center of the ultra high redshift galaxy. That makes UHZ1's growing black hole the most distant black hole ever dete...

The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous 18th century list of things which are not comets. In fact, the Crab is now known to be a supernova remnant , debris from the death explosion of a massive star witnessed by astronomers in the year 1054. This sharp image from the James Webb Space Telescope’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) explores the eerie glow and fragmented strands of the still expanding cloud of interstellar debris in infrared light. One of the most exotic objects known to modern astronomers, the Crab Pulsar , a neutron star spinning 30 times a second, is visible as a bright spot near the nebula's center. Like a cosmic dynamo , this collapsed remnant of the stellar core powers the Crab's emission across the electromagnetic spectrum. Spanning about 12 light-years, the Crab Nebula is a mere 6,500 light-years away in the head-strong constellation Taurus . from NASA https://ift.tt/s4gAY...

There's a new space telescope in the sky: Euclid . Equipped with two large panoramic cameras, Euclid captures light from the visible to the near- infrared . It took five hours of observing for Euclid's 1.2-meter diameter primary mirror to capture, through its sharp optics , the 1000+ galaxies in the Perseus cluster , which lies 250 million light years away. More than 100,000 galaxies are visible in the background, some as far away as 10 billion light years. The revolutionary nature of Euclid lies in the combination of its wide field of view (twice the area of the full moon), its high angular resolution (thanks to its 620 Megapixel camera ), and its infrared vision, which captures both images and spectra . Euclid's initial surveys , covering a third of the sky and recording over 2 billion galaxies, will enable a study of how dark matter and dark energy have shaped our universe . from NASA https://ift.tt/68XD3kt

It moved across the surface of Mars -- what was it? A dust devil . Such spinning columns of rising air are heated by the warm surface and are also common in warm and dry areas on planet Earth . Typically lasting only a few minutes, dust devils become visible as they pick up loose red-colored dust, leaving the darker and heavier sand beneath intact. Dust devils not only look cool -- they can leave visible trails , and have been credited with unexpected cleanings of the surfaces of solar panels . The images in the featured AI-interpolated video were captured in early August by the Perseverance rover currently searching for signs of ancient life in Jezero Crater. The six-second time-lapse video encapsulates a real duration of just over one minute. Visible in the distance, the spinning dust devil was estimated to be passing by at about 20 kilometers per hour and extend up about 2 kilometers high. from NASA https://ift.tt/xP1XQuA

What was that red glow on the horizon last night? Aurora. Our unusually active Sun produced a surface explosion a few days ago that sent out a burst of electrons, protons, and more massive charged nuclei. This coronal mass ejection (CME) triggered auroras here on Earth that are being reported unusually far south in Earth's northern hemisphere . For example, this was the first time that the astrophotographer captured aurora from her home country of Italy . Additionally, many images from these auroras appear quite red in color . In the featured image , the town of Comelico Superiore in the Italian Alps is visible in the foreground, with the central band of our Milky Way galaxy seen rising from the lower left. What draws the eye the most, though, is the bright red aurora on the far right. The featured image is a composite with the foreground and background images taken consecutively with the same camera and from the same location. from NASA https://ift.tt/BFuvYdS

It was Halloween and the sky looked like a creature. Exactly which creature, the astrophotographer was unsure (but possibly you can suggest one ). Exactly what caused this eerie apparition in 2013 was sure: one of the best auroral displays that year. This spectacular aurora had an unusually high degree of detail . Pictured here , the vivid green and purple auroral colors are caused by high atmospheric oxygen and nitrogen reacting to a burst of incoming electrons . Birch trees in Tromsø , Norway formed an also eerie foreground . Frequently, new photogenic auroras accompany new geomagnetic storms . from NASA https://ift.tt/uV0jyxn

Last Wednesday the voyaging Lucy spacecraft encountered its first asteroid, 152830 Dinkinesh, and discovered the inner-main belt asteroid has a moon. From a distance of just over 400 kilometers, Lucy's Long-Range Reconnaissance Imager captured this close-up of the binary system during a flyby at 4.5 kilometer per second or around 10,000 miles per hour. A marvelous world, Dinkinesh itself is small, less than 800 meters (about 0.5 miles) across at its widest. Its satellite is seen from the spacecraft's perspective to emerge from behind the primary asteroid. The asteroid moon is estimated to be only about 220 meters wide. from NASA https://ift.tt/U5vFSch

That bright beacon you've seen rising in the east just after sunset is Jupiter. Climbing high in midnight skies, our Solar System's ruling gas giant was at its 2023 opposition, opposite the Sun in planet Earth's sky, on November 2. But only a few days earlier, on October 28, the Moon was at its own opposition. Then both Full Moon and Jupiter could share this telephoto field of view. The celestial scene is composed from two exposures, one long and one short, blended to record bright planet and even brighter Moon during that evening's partial lunar eclipse . Moonlight shining through the thin, high clouds over northern Italy creates the colorful iridescence and lunar corona . Look closely and you'll also spot some of Jupiter's Galilean moons . from NASA https://ift.tt/nP8FHcr

Named for the southern constellation toward which most of its galaxies can be found, the Fornax Cluster is one of the closest clusters of galaxies. About 62 million light-years away, it's over 20 times more distant than our neighboring Andromeda Galaxy , but only about 10 percent farther along than the better known and more populated Virgo Galaxy Cluster . Seen across this three degree wide field-of-view, almost every yellowish splotch on the image is an elliptical galaxy in the Fornax cluster. Elliptical galaxies NGC 1399 and NGC 1404 are the dominant, bright cluster members toward the bottom center. A standout, large barred spiral galaxy, NGC 1365 , is visible on the upper right as a prominent Fornax cluster member. from NASA https://ift.tt/9GFulPK

Part of the Sun disappeared earlier this month, but few people were worried. The missing part, which included the center from some locations, just went behind the Moon in what is known as an annular solar eclipse . Featured here is an eclipse sequence taken as the Moon was overtaking the rising Sun in the sky. The foreground hill is Factory Butte in Utah , USA . The rays flaring out from the Sun are not real -- they result from camera aperture diffraction and are known as sunstar . The Moon is real , but it is artificially brightened to enhance its outline -- which helps the viewer better visualize the Moon's changing position during this ring-of-fire eclipse . As stunning as this eclipse sequence is, it was considered just practice by the astrophotographer. The reason? She hopes to use this experience to better photograph the total solar eclipse that will occur over North America on April 8, 2024. from NASA https://ift.tt/lX8vNc6

Halloween's origin is ancient and astronomical. Since the fifth century BC, Halloween has been celebrated as a cross-quarter day , a day halfway between an equinox (equal day / equal night) and a solstice (minimum day / maximum night in the northern hemisphere). With a modern calendar however, even though Halloween occurs today, the real cross- quarter day will occur next week . Another cross-quarter day is Groundhog Day . Halloween's modern celebration retains historic roots in dressing to scare away the spirits of the dead. Perhaps a fitting tribute to this ancient holiday is this closeup view of the Wizard Nebula (NGC 7380). Visually, the interplay of stars, gas, and dust has created a shape that appears to some like a fictional ancient sorcerer . Although the nebula may last only a few million years, some of the stars being conjured from the gas by the great gravitational powers may outlive our Sun. from NASA https://ift.tt/l3f9wyH

Do any shapes seem to jump out at you from this interstellar field of stars and dust? The jeweled expanse, filled with faint, starlight-reflecting clouds, drifts through the night in the royal constellation of Cepheus . Far from your own neighborhood on planet Earth , these ghostly apparition s lurk along the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over two light-year s across and brighter than the other spooky chimera s, VdB 141 or Sh2-136 is also known as the Ghost Nebula , seen toward the bottom of the featured image . Within the reflection nebula are the telltale signs of dense cores collapsing in the early stages of star formation. from NASA https://ift.tt/PHR2ki6

What's happened to the Moon? Within the last day, part of the Moon moved through the Earth's shadow . This happens about once or twice a year , but not every month since the Moon's orbit around the Earth is slightly tilted . Pictured here, the face of a full Hunter's Moon is shown twice from Italy during this partial lunar eclipse . On the left, most of the Moon appears over exposed except for the eclipsed bottom right, which shows some familiar lunar surface details. In contrast, on the right, most of the (same) Moon appears normally exposed, with the exception of the bottom right, which now appears dark. All lunar eclipses are visible from the half of the Earth facing the Moon at the time of the eclipse, but this eclipse was visible specifically from Europe , Africa , Asia , and Australia , clouds permitting . In April, a total solar eclipse will be visible from North America . from NASA https://ift.tt/pM8wbrt

Gamma Cassiopeiae shines high in northern autumn evening skies. It's the brightest spiky star in this telescopic field of view toward the constellation Cassiopeia. Gamma Cas shares the ethereal-looking scene with ghostly interstellar clouds of gas and dust, IC 59 (top left) and IC 63. About 600 light-years distant, the clouds aren't actually ghosts. They are slowly disappearing though, eroding under the influence of energetic radiation from hot and luminous gamma Cas. Gamma Cas is physically located only 3 to 4 light-years from the nebulae. Slightly closer to gamma Cas, IC 63 is dominated by red H-alpha light emitted as hydrogen atoms ionized by the star's ultraviolet radiation recombine with electrons. Farther from the star, IC 59 shows proportionally less H-alpha emission but more of the characteristic blue tint of dust reflected star light . The cosmic stage spans over 1 degree or 10 light-years at the estimated distance of gamma Cas and friends . from NASA http...

History's second known periodic comet is Comet Encke (2P/Encke) . As it swings through the inner Solar System, Encke's orbit takes it from an aphelion, its greatest distance from the Sun, inside the orbit of Jupiter to a perihelion just inside the orbit of Mercury. Returning to its perihelion every 3.3 years, Encke has the shortest period of the Solar System's major comets . Comet Encke is also associated with ( at least ) two annual meteor showers on planet Earth, the North and South Taurids . Both showers are active in late October and early November. Their two separate radiants lie near bright star Aldebaran in the head-strong constellation Taurus. A faint comet, Encke was captured in this telescopic field of view imaged on the morning of August 24. Then, Encke's pretty greenish coma was close on the sky to the young, embedded star cluster and light-years long, tadpole-shaped star-forming clouds in emission nebula IC 410. Now near bright star Spica in Virgo Come...

History's first known periodic comet, Comet Halley (1P/Halley) , returns to the inner Solar System every 76 years or so. The famous comet made its last appearance to the naked-eye in 1986. But dusty debris from Comet Halley can be seen raining through planet Earth's skies twice a year during two annual meteor showers, the Eta Aquarids in May and the Orionids in October . In fact, an unhurried series of exposures captured these two bright meteors, vaporizing bits of Halley dust, during the early morning hours of October 23 against a starry background along the Taurus molecular cloud. Impacting the atmosphere at about 66 kilometers per second their greenish streaks point back to the shower's radiant just north of Orion's bright star Betelgeuse off the lower left side of the frame. The familiar Pleiades star cluster anchors the dusty celestial scene at the right. from NASA https://ift.tt/mbHQ5xD

In 60 seconds, this setting Sun will turn green. Actually, the top of the Sun already appears not only green, but wavey -- along with all of its edges. The Sun itself is unchanged -- both effects are caused by looking along hot and cold layers in Earth's atmosphere . The unusual color is known as a green flash and occurs because these atmospheric layers not only shift background images but disperse colors into slightly different directions, like a prism . The featured video was captured earlier this month off the coast of Hawai i , USA . After waiting those 60 seconds, at the video's end, the upper part of the Sun seems to hover alone in space, while turning not only green , but blue . Then suddenly, the Sun appears to shrink to nothing -- only to return tomorrow. from NASA https://ift.tt/jDV6oxH

This dance is to the death. As these two large galaxies duel, a cosmic bridge of stars, gas, and dust currently stretches over 75,000 light-years and joins them. The bridge itself is strong evidence that these two immense star systems have passed close to each other and experienced violent tides induced by mutual gravity. As further evidence, the face-on spiral galaxy on the right, also known as NGC 3808A, exhibits many young blue star clusters produced in a burst of star formation. The twisted edge-on spiral on the left (NGC 3808B) seems to be wrapped in the material bridging the galaxies and surrounded by a curious polar ring . Together, the system is known as Arp 87 . While such interactions are drawn out over billions of years, repeated close passages will ultimately create one merged galaxy. Although this scenario does look unusual, galactic mergers are thought to be common, with Arp 87 representing a stage in this inevitable process . The Arp 87 dancing pair are about 30...

There goes another one! Volcanoes on Jupiter 's moon Io keep erupting. To investigate, NASA 's robotic Juno spacecraft has begun a series of visits to this very strange moon. Io is about the size of Earth's moon , but because of gravitational flexing by Jupiter and other moons, Io's interior gets heated and its surface has become covered with volcanoes . The featured image is from last week's flyby , passing within 12,000 kilometers above the dangerously active world. The surface of Io is covered with sulfur and frozen sulfur dioxide, making it appear yellow, orange and brown. As hoped, Juno flew by just as a volcano was erupting -- with its faint plume visible near the top of the featured image. Studying Io's volcanoes and plumes helps humanity better understand how Jupiter's complex system of moons, rings, and auroras interact. Juno is scheduled to make two flybys of Io during the coming months that are almost 10 times closer: one in December and...

What does this aurora look like to you? While braving the cold to watch the skies above northern Canada early one morning in 2013, a most unusual aurora appeared. The aurora definitely appeared to be shaped like something , but what? Two ghostly possibilities recorded by the astrophotographer were "witch" and "goddess of dawn", but please feel free to suggest your own Halloween-enhanced impressions. Regardless of fantastical pareidolic interpretations, the pictured aurora had a typical green color and was surely caused by the scientifically commonplace action of high-energy particles from space interacting with oxygen in Earth's upper atmosphere . In the image foreground, at the bottom, is a frozen Alexandra Falls , while evergreen trees cross the middle. from NASA https://ift.tt/QMXZHrd

Half way between New Moon and Full Moon is the Moon's first quarter phase . That's a quarter of the way around its moonthly orbit. At the first quarter phase, half the Moon's visible side is illuminated by sunlight. For the Moon's third quarter phase, half way between Full Moon and New Moon, sunlight illuminates the other half of the visible lunar disk. At both first and third quarter phases, the terminator, or shadow line separating the lunar night and day, runs down the middle. Near the terminator , long shadows bring lunar craters and mountains in to sharp relief, making the quarter phases a good time to observe the Moon. But in case you missed some, all the quarter phases of the Moon and their calendar dates during 2022 can be found in this well-planned array of telephoto images. Of course, you can observe a first quarter Moon tonight. from NASA https://ift.tt/4dc7E68

Galaxies abound in this sharp telescopic image recorded on October 12 in dark skies over June Lake, California. The celestial scene spans nearly 2 degrees within the boundaries of the well-trained northern constellation Canes Venatici. Prominent at the upper left 23.5 million light-years distant is big, beautiful spiral galaxy NGC 4258, known to some as Messier 106 . Eye-catching edge-on spiral NGC 4217 is above and right of center about 60 million light-years away. Just passing through the pretty field of view is comet C/2023 H2 Lemmon , discovered last April in image data from the Mount Lemmon Survey . Here the comet sports more of a lime green coma though, along with a faint, narrow ion tail stretching toward the top of the frame. This visitor to the inner Solar System is presently less than 7 light-minutes away and still difficult to spot with binoculars, but it's growing brighter. Comet C/2023 H2 Lemmon will reach perihelion, its closest point to the Sun, on October 29 and...

This timelapse series captured on October 14 is set against the sunrise view from Sunset Point, Bryce Canyon, planet Earth . Of course on that date the New Moon caught up with the Sun in the canyon's morning skies. Local temperatures fell as the Moon's shadow swept across the high altitude scene and the brilliant morning sunlight became a more subdued yellow hue cast over the reddish rocky landscape. In the timelapse series, images were taken at 2 minute intervals. The camera and solar filter were fixed to a tripod to follow the phases of the annular solar eclipse . from NASA https://ift.tt/uXge4tF

It's so big it is easy to miss. The entire Veil Nebula spans six times the diameter of the full moon , but is so dim you need binoculars to see it. The nebula was created about 15,000 years ago when a star in the constellation of the Swan ( Cygnus ) exploded. The spectacular explosion would have appeared brighter than even Venus for a week - but there is no known record of it. Pictured is the western edge of the still-expanding gas cloud. Notable gas filaments include the Witch's Broom Nebula on the upper left near the bright foreground star 52 Cygni , and Fleming's Triangular Wisp (formerly known as Pickering's Triangle ) running diagonally up the image middle. What is rarely imaged -- but seen in the featured long exposure across many color bands -- is the reflecting brown dust that runs vertically up the image left, dust likely created in the cool atmospheres of massive stars . from NASA https://ift.tt/shxlkGY

It's not the big ring that's attracting the most attention. Although the big planet-forming ring around the star PDS 70 is clearly imaged and itself quite interesting. It's also not the planet on the right, just inside the big disk , that’s being talked about the most. Although the planet PDS 70 c is a newly formed and, interestingly, similar in size and mass to Jupiter . It's the fuzzy patch around the planet PDS 70c that's causing the commotion . That fuzzy patch is thought to be a dusty disk that is now forming into moons -- and that had never been seen before. The featured image was taken in 2021 by the Atacama Large Millimeter Array (ALMA) of 66 radio telescopes in the high Atacama Desert of northern Chile . Based on ALMA data, astronomers infer that the moon-forming exoplanetary disk has a radius similar to our Earth's orbit, and may one day form three or so Luna -sized moons -- not very different from our Jupiter 's four . from NASA https...

She knew everything but the question. She was well aware that there would be a complete annular eclipse of the Sun visible from their driving destination: Lake Abert in Oregon . She knew that the next ring-of-fire eclipse would occur in the USA only in 16 more years , making this a rare photographic opportunity. She was comfortable with the plan: that she and her boyfriend would appear in front of the eclipse in silhouette , sometimes alone, and sometimes together. She knew that the annular phase of this eclipse would last only a few minutes and she helped in the many hours of planning . She could see their friend who set up the camera about 400 meters away at the bottom of a ridge. What she didn't know was the question she would be asked. But she did know the answer: "yes". from NASA https://ift.tt/bDed5yk

Yes, but can your tree do this? If you look closely at the ground in the featured image, you will see many images of yesterday's solar eclipse -- created by a tree. Gaps between tree leaves act like pinhole lenses and each create a small image of the partially eclipsed Sun visible in the other direction. The image was taken in Burleson , Texas , USA . Yesterday, people across the Americas were treated to a partial eclipse of the Sun, when the Moon moves in front of part of the Sun. People in a narrow band of Earth were treated to an annular eclipse , also called a ring-of-fire eclipse , when the Moon becomes completely engulfed by the Sun and sunlight streams around all of the Moon's edges . In answer to the lede question, your tree not only can do this , but will do it every time that a visible solar eclipse passes overhead. Next April 8, a deeper, total solar eclipse will move across North America . from NASA https://ift.tt/Frpo8dJ

Want to see a ring around the Sun? It's easy to do in daytime skies around the world. Created by randomly oriented ice crystals in thin high cirrus clouds, circular 22 degree halos are visible much more often than rainbows. This one was captured by smart phone photography on May 29, 2021 near Rome, Italy. Carefully blocking the Sun , for example with a finger tip, is usually all that it takes to reveal the common bright halo ring. The halo's characteristic angular radius is about equal to the span of your hand, thumb to little finger, at the end of your outstretched arm. Want to see a ring of fire eclipse ? That's harder. The spectacular annular phase of today's (October 14) solar eclipse , known as a ring of fire , is briefly visible only when standing along the Moon's narrow shadow track that passes over limited parts of North, Central, and South America. The solar eclipse is partial though, when seen from broader regions throughout the Americas. from NASA h...

Gorgeous spiral galaxy Messier 33 seems to have more than its fair share of glowing hydrogen gas. A prominent member of the local group of galaxies, M33 is also known as the Triangulum Galaxy and lies a mere 3 million light-years away. The galaxy's central 30,000 light-years or so are shown in this sharp galaxy portrait . The portrait features M33's reddish ionized hydrogen clouds or HII regions . Sprawling along loose spiral arms that wind toward the core, M33's giant HII regions are some of the largest known stellar nurseries, sites of the formation of short-lived but very massive stars. Intense ultraviolet radiation from the luminous, massive stars ionizes the surrounding hydrogen gas and ultimately produces the characteristic red glow. In this image, broadband data were combined with narrowband data recorded through a hydrogen-alpha filter. That filter transmits the light of the strongest visible hydrogen emission line . from NASA https://ift.tt/ROFhfAI