Alpha News

Is star AE Aurigae on fire? No. Even though AE Aurigae is named the Flaming Star and the surrounding nebula IC 405 is named the Flaming Star Nebula , and even though the nebula appears to some like a swirling flame , there is no fire . Fire , typically defined as the rapid molecular acquisition of oxygen , happens only when sufficient oxygen is present and is not important in such high-energy, low-oxygen environments such as stars. The bright star AE Aurigae occurs near the center of the Flaming Star Nebula and is so hot it glows blue , emitting light so energetic it knocks electrons away from surrounding gas. When a proton recaptures an electron, light is emitted, as seen in the surrounding emission nebula . Captured here three weeks ago, the Flaming Star Nebula is visible near the composite image's center, between the red Tadpole Nebula on the left and blue-tailed Comet ZTF on the right. The Flaming Star Nebula lies about 1,500 light years distant, spans about 5 light...

Why is a thin crescent moon never seen far from a horizon? Because the only geometry that gives a thin crescent lunar phase occurs when the Moon appears close to the Sun in the sky. The crescent is not caused by the shadow of the Earth , but by seeing only a small part of the Moon directly illuminated by the Sun. Moreover, the thickest part of the crescent always occurs in the direction of the Sun. In the evening, a thin crescent Moon will set shortly after the Sun and not be seen for the rest of the night. Alternatively, in the morning, a crescent Moon will rise shortly before the Sun after not being seen for most of the night. Pictured two weeks ago, a crescent moon was captured near the horizon, just before sunrise, far behind remnants of the ancient Temple of Poseidon in Greece . from NASA https://ift.tt/GkNDQ9p

By Oliver Whang from NYT Science https://ift.tt/yozKtiQ

What's causing that unusual ray of light extending from the horizon? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently after sunset or before sunrise and is called zodiacal light . The dust was emitted mostly from faint Jupiter-family comets and slowly spirals into the Sun . The featured HDR image , acquired in mid-February from the Sierra Nevada National Park in Spain , captures the glowing band of zodiacal light going right in front of the bright evening planets Jupiter (upper) and Venus (lower). Emitted from well behind the zodiacal light is a dark night sky that prominently includes the Pleiades star cluster . Jupiter and Venus are slowly switching places in the evening sky , and just in the next few days nearing their closest angular approach . from NASA https://ift.tt/TFrYJts

What would make a moon look like a walnut? A strange ridge that circles Saturn 's moon Iapetus 's equator, visible near the bottom of the featured image , makes it appear similar to a popular edible nut . The origin of the ridge remains unknown, though, with hypotheses including ice that welled up from below, a ring that crashed down from above, and structure left over from its formation perhaps 100 million years ago. Also strange is that about half of Iapetus is so dark that it can nearly disappear when viewed from Earth, while the rest is, reflectively, quite bright. Observations show that the degree of darkness of the terrain is strangely uniform, as if a dark coating was somehow recently applied to an ancient and highly cratered surface. Last, several large impact basins occur around Iapetus , with a 400-kilometer wide crater visible near the image center, surrounded by deep cliffs that drop sharply to the crater floor. The featured image was taken by the Saturn-orbi...

On February 22, a young Moon shared the western sky at sunset with bright planets Venus and Jupiter along the ecliptic plane . The beautiful celestial conjunction was visible around planet Earth . But from some locations Jupiter hid for a while, occulted by the crescent lunar disk. The Solar System's ruling gas giant was captured here just before it disappeared behind the the Moon's dark edge, seen over the Río de la Plata at Colonia del Sacramento, Uruguay. In the serene river and skyscape Venus is not so shy, shining brightly closer to the horizon through the fading twilight. Next week Venus and Jupiter will appear even closer in your evening sky. from NASA https://ift.tt/swpqyjk

Planetary nebula Jones-Emberson 1 is the death shroud of a dying Sun-like star. It lies some 1,600 light-years from Earth toward the sharp-eyed constellation Lynx . About 4 light-years across, the expanding remnant of the dying star's atmosphere was shrugged off into interstellar space, as the star's central supply of hydrogen and then helium for fusion was finally depleted after billions of years. Visible near the center of the planetary nebula is what remains of the stellar core, a blue-hot white dwarf star . Also known as PK 164 +31.1, the nebula is faint and very difficult to glimpse at a telescope's eyepiece. But this deep broadband image combining 22 hours of exposure time does show it off in exceptional detail. Stars within our own Milky Way galaxy as well as background galaxies across the universe are scattered through the clear field of view. Ephemeral on the cosmic stage, Jones-Emberson 1 will fade away over the next few thousand years. Its hot, central whit...

Peculiar spiral galaxy Arp 78 is found within the boundaries of the head strong constellation Aries . Some 100 million light-years beyond the stars and nebulae of our Milky Way galaxy, the island universe is an enormous 200,000 light-years across. Also known as NGC 772 , it sports a prominent, outer spiral arm in this detailed cosmic portrait . Tracking along sweeping dust lanes and lined with young blue star clusters, Arp 78's overdeveloped spiral arm is pumped-up by galactic-scale gravitational tides. Interactions with its brightest companion galaxy, the more compact NGC 770 seen above and right of the larger spiral, are likely responsible. Embedded in faint star streams revealed in the deep telescopic exposure, NGC 770's fuzzy, elliptical appearance contrasts nicely with spiky foreground Milky Way stars in matching yellowish hues. from NASA https://ift.tt/WdgCsfM

Our Sun is becoming a busy place. Only two years ago, the Sun was emerging from a solar minimum so quiet that month s would go by without even a single sunspot . In contrast, already this year and well ahead of schedule, our Sun is unusually active , already nearing solar activity levels seen a decade ago during the last solar maximum . Our increasingly active Sun was captured two weeks ago sporting numerous interesting features. The image was recorded in a single color of light called Hydrogen Alpha , color-inverted, and false colored. Spicules carpet much of the Sun's face. The brightening towards the Sun's edges is caused by increased absorption of relatively cool solar gas and called limb darkening . Just outside the Sun's disk , several scintillating prominences protrude , while prominences on the Sun's face are known as filaments and show as light streaks. Magnetically tangled active regions are both dark and light and contain cool sunspots . As our Sun...

They are both falling. The water in Yosemite Falls , California , USA , is falling toward the Earth. Comet ZTF is falling toward the Sun . This double cosmic cascade was captured late last month as fading Comet C/2022 E3 (ZTF) had just passed its closest to planet Earth. The orange star just over the falls is Kochab . With the exception of a brief encounter with a black bear , the featured image was a well-planned composite of a moonlit-foreground and long-duration background exposures - all designed to reconstruct a deep version of an actual single sight. Although Comet ZTF is now fading as it glides back to the outer Solar System , its path is determined by gravity and so it can be considered to still be falling toward the Sun -- but backwards. from NASA https://ift.tt/VUr0p8g

There is nothing like this ball of stars in our Milky Way Galaxy. This is surprising because, at first glance, this featured image by the Hubble Space Telescope suggests that star cluster NGC 1850 's size and shape are reminiscent of the many ancient globular star clusters which roam our own Milky Way Galaxy's halo . But NGC 1850's stars are all too young, making it a type of star cluster with no known counterpart in the Milky Way. Moreover, NGC 1850 is also a double star cluster , with a second, compact cluster of stars visible here just to the right of the large cluster's center. Stars in the large cluster are estimated to be 50 million years young, while stars in the compact cluster are younger still, with an age of about 4 million years. A mere 168,000 light-years distant, NGC 1850 is located near the outskirts of the Large Magellanic Cloud galaxy. The glowing gas filaments across the image left, like supernova remnants in our own galaxy, testify to violen...

Is this really the famous Pleiades star cluster? Known for its iconic blue stars , the Pleiades is shown here in infrared light where the surrounding dust outshines the stars. Here three infrared colors have been mapped into visual colors (R=24, G=12, B=4.6 micron s). The base images were taken by NASA's orbiting Wide Field Infrared Survey Explorer (WISE) spacecraft. Cataloged as M45 and nicknamed the Seven Sisters , the Pleiades star cluster is by chance situated in a passing dust cloud . The light and wind s from the massive Pleiades stars preferentially repel smaller dust particles , causing the dust to become stratified into filaments , as seen. The featured image spans about 20 light years at the distance of the Pleiades , which lies about 450 light years distant toward the constellation of the Bull ( Taurus ). from NASA https://ift.tt/cf7LDNl

A mere 56 million light-years distant toward the southern constellation Fornax, NGC 1365 is an enormous barred spiral galaxy about 200,000 light-years in diameter. That's twice the size of our own barred spiral Milky Way. This sharp image from the James Webb Space Telescope 's Mid-Infrared Instrument (MIRI) reveals stunning details of this magnificent spiral in infrared light . Webb's field of view stretches about 60,000 light-years across NGC 1365, exploring the galaxy's core and bright newborn star clusters. The intricate network of dusty filaments and bubbles is created by young stars along spiral arms winding from the galaxy's central bar. Astronomers suspect the gravity field of NGC 1365's bar plays a crucial role in the galaxy's evolution, funneling gas and dust into a star-forming maelstrom and ultimately feeding material into the active galaxy's central, supermassive black hole . from NASA https://ift.tt/0pN7TJZ

While scanning the skies for near earth objects Hungarian astronomer Krisztián Sárneczky first imaged the meter-sized space rock now cataloged as 2023 CX1 on 12 February 2023 at 20:18:07 UTC. That was about 7 hours before it impacted planet Earth's atmosphere. Its predicted trajectory created a rare opportunity for meteor observers and a last minute plan resulted in this spectacular image of the fireball, captured from the Netherlands as 2023 CX1 vaporized and broke up over northern France. Remarkably it was Sárneczky's second discovery of an impacting asteroid, while 2023 CX1 is only the seventh asteroid to be detected before being successfully predicted to impact Earth. It has recently become the third such object from which meteorites have been recovered . This fireball was witnessed almost 10 years to the day following the infamous Chelyabinsk Meteor flash . from NASA https://ift.tt/pzwltEP

This unusual sky was both familiar and unfamiliar. The photographer's mission was to capture the arch of the familiar central band of our Milky Way Galaxy over a picturesque medieval manor . The surprise was that on this January evening, the foreground sky was found glowing in a beautiful but unfamiliar manner. The striped bands are called airglow and they result from air high in Earth's atmosphere being excited by the Sun's light and emitting a faint light of its own. The bands cross the entire sky -- their curved appearance is due to the extremely wide angle of the camera lens. In the foreground lies Château de Losse in southwest France . Other familiar sky delights dot the distant background including the bright white star Sirius , the orange planet Mars , the blue Pleiades star cluster, the red California Nebula , and, on the far right, the extended Andromeda Galaxy . The initial mission was also successful: across the top of the frame is the arching band ...

Is the heart and soul of our Galaxy located in Cassiopeia ? Possibly not, but that is where two bright emission nebulas nicknamed Heart and Soul can be found. The Heart Nebula , officially dubbed IC 1805 and visible in the featured image on the upper right, has a shape reminiscent of a classical heart symbol . The shape is perhaps fitting for Valentine's Day . The Soul Nebula is officially designated IC 1871 and is visible on the lower left. Both nebulas shine brightly in the red light of energized hydrogen , one of three colors shown in this three-color montage . Light takes about 6,000 years to reach us from these nebulas , which together span roughly 300 light years . Studies of stars and clusters like those found in the Heart and Soul nebulas have focused on how massive stars form and how they affect their environment . from NASA https://ift.tt/OMNhHXD

No, Comet ZTF is not going to hit Mars. Nicknamed the Green Comet for its bright green coma, C/2022 E3 (ZTF) did, however, pass almost in front of the much-more distant planet a few days ago, very near in time to when the featured picture was taken. The two sky icons were here captured behind a famous Earth icon -- the Matterhorn , a mountain in the Italian Alps with a picturesque peak . Both the foreground and background images were taken on the same evening by the same camera and from the same location. The comet's white dust tail is visible to the right of the green coma , while the light blue ion tail trails towards the top of the image. Orange Mars is well in front of the numerous background stars as well as the dark nebula Barnard 22 to its lower right. Although Mars remains visible in the evening sky for the next few months, Comet ZTF has already begun to fade as it returns to the outer Solar System . from NASA https://ift.tt/JU1KITE

When do cloud bottoms appear like bubbles? Normally, cloud bottoms are flat . This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. As water droplets grow , an opaque cloud forms. Under some conditions, however, cloud pockets can develop that contain large droplets of water or ice that fall into clear air as they evaporate. Such pocket s may occur in turbulent air near a thunderstorm . Resulting mammatus clouds can appear especially dramatic if sunlit from the side. The mammatus clouds pictured here were photographed over Hastings , Nebraska during 2004 June. from NASA https://ift.tt/AiqCBFd

The two prominent clouds in this Chilean Atacama Desert skyscape captured on January 21 actually lie beyond our Milky Way galaxy. Known as the Large and the Small Magellanic Clouds they are so named for the 16th century Portuguese explorer Ferdinand Magellan, leader of the first circumnavigation of planet Earth. Famous jewels of southern hemisphere skies, they are the brightest satellite galaxies of the Milky Way. The larger cloud is some 160,000 light-years, and the smaller 210,000 light-years distant. While both are irregular dwarf galaxies in their own right, they exhibit central barred structures in the deep wide-angle view. Wide and deep exposures also reveal faint dusty galactic cirrus nebulae and the imprints of gravitational tidal interactions between the Large and Small Magellanic Clouds . from NASA https://ift.tt/6T0W3g9

Fading as it races across planet Earth's northern skies comet C/2022 E3 (ZTF) shares this telescopic frame with comet C/2022 U2 (ATLAS) . Captured on the night of February 6 from a garden observatory in Germany's Bavarian Forest, the starry field of view toward the constellation Auriga spans about 2.5 degrees. Discovered by sky survey projects in 2022 (the Zwicky Transient Facility and the Asteroid Terrestrial-impact Last Alert System ) these long-period comets are outbound, reaching perihelion just last month. The much fainter comet ATLAS made its closest approach to our fair planet on January 29 at a distance of about 4.6 light-minutes, compared to a mere 2.4 light-minutes for comet ZTF on February 2. This comet ATLAS lacks the well-developed tails of the formerly naked-eye comet ZTF . But both comets sport greenish tinted comas, emission from diatomic carbon molecules fluorescing in sunlight. Continuing its dash across planet Earth's sky, the good-binocular comet Z...

By Jack Tamisiea from NYT Science https://ift.tt/ZEj9740

By Amanda Holpuch from NYT Science https://ift.tt/kwl9ebq

Vivid and lustrous, wafting iridescent waves of color wash across this skyscape from Kilpisjärvi, Finland. Known as nacreous clouds or mother-of-pearl clouds, they are rare. But their unforgettable appearance was captured looking south at 69 degrees north latitude at sunset on January 24. A type of polar stratospheric cloud , they form when unusually cold temperatures in the usually cloudless lower stratosphere form ice crystals. Still sunlit at altitudes of around 15 to 25 kilometers, the clouds can diffract sunlight even after sunset and just before the dawn. from NASA https://ift.tt/ohHAxz7

Imagine traveling to a star about 100 times as massive as our Sun, a million times more luminous, and with 30 times the surface temperature. Such stars exist, and some are known as Wolf Rayet (WR) stars, named after French astronomers Charles Wolf and Georges Rayet . The central star in this image is WR 40 which is located toward the constellation of Carina . Stars like WR 40 live fast and die young in comparison with the Sun . They quickly exhaust their core hydrogen supply, move on to fusing heavier core elements , and expand while ejecting their outer layers via high stellar winds . In this case, the central star WR 40 ejects the atmosphere at a speed of nearly 100 kilometers per second , and these outer layers have become the expanding oval-shaped nebula RCW 58 . from NASA https://ift.tt/PjKJ5zS

Can you still see the comet? Yes. Even as C/2022 E3 (ZTF) fades, there is still time to see it if you know where and when to look. Geometrically, Comet ZTF has passed its closest to both the Sun and the Earth and is now headed back to the outer Solar System . Its orbit around the Sun has it gliding across the northern sky all month, after passing near Polaris and both the Big and Little Dipper s last month. Pictured , Comet ZTF was photographed between the two dippers in late January while sporting an ion tail that extended over 10 degrees . Now below naked-eye visibility, Comet ZTF can be found with binoculars or a small telescope and a good sky map . A good time to see the comet over the next week is after the Sun sets -- but before the Moon rises . The comet will move nearly in front of Mars in a few days from NASA https://ift.tt/Grkhyoi

In the heart of the Rosette Nebula lies a bright cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only a few million years ago. The featured image taken in mid-January using multiple exposures and very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue), captures the central region in tremendous detail. A hot wind of particles streams away from the cluster stars and contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. The Rosette Nebula 's center measures about 50 light-years across, lies about 5,200 light-years away, and is visible with binoculars towards the constellation of the Unicorn ( Monoceros ). from NASA https://ift.tt/veXFH8l

This moon is shining by the light of its planet. Specifically, a large portion of Enceladus pictured here is illuminated primarily by sunlight first reflected from the planet Saturn . The result is that the normally snow-white moon appears in the gold color of Saturn's cloud tops . As most of the illumination comes from the image left, a labyrinth of ridges throws notable shadows just to the right of the image center, while the kilometer-deep canyon Labtayt Sulci is visible just below. The bright thin crescent on the far right is the only part of Enceladus directly lit by the Sun. The featured image was taken in 2011 by the robotic Cassini spacecraft during a close pass by by the enigmatic moon. Inspection of the lower left part of this digitally sharpened image reveals plumes of ice crystals thought to originate in a below-surface sea . from NASA https://ift.tt/GUshfvy

Centered in this colorful cosmic canvas, NGC 2626 is a beautiful , bright, blue reflection nebula in the southern Milky Way. Next to an obscuring dust cloud and surrounded by reddish hydrogen emission from large H II region RCW 27 it lies within a complex of dusty molecular clouds known as the Vela Molecular Ridge . NGC 2626 is itself a cloud of interstellar dust reflecting blue light from the young hot embedded star visible within the nebula. But astronomical explorations reveal many other young stars and associated nebulae in the star-forming region. NGC 2626 is about 3,200 light-years away. At that distance this telescopic field of view would span about 30 light-years along the Vela Molecular Ridge . from NASA https://ift.tt/2hmraxg

By Kenneth Chang from NYT Science https://ift.tt/qUW9kt3

Stars trace concentric arcs around the North Celestial Pole in this three hour long night sky composite , recorded with a digital camera fixed to a tripod on January 31, near Àger, Lleida, Spain. On that date Comet C/2022 E3 (ZTF) was near its northernmost declination in planet Earth's sky . That put the comet about 10 degrees from Earth's North Celestial Pole making the comet's position circumpolar , always above the horizon, from all locations on planet Earth at more than 10 degrees northern latitude. In the startrail image, the extension of Earth's axis of rotation into space is at the left. North star Polaris traces the short, bright, concentric arc less than a degree from the North Celestial Pole. The trail of Comet ZTF is indicated at the right, its apparent motion mostly reflecting Earth's rotation like the stars. But heading for its closest approach to planet Earth on February 1, the comet is also moving significantly with respect to the background st...

The 1970s are sometimes ignored by astronomers, like this beautiful grouping of reflection nebulae in Orion - NGC 1977, NGC 1975, and NGC 1973 - usually overlooked in favor of the substantial glow from the nearby stellar nursery better known as the Orion Nebula . Found along Orion's sword just north of the bright Orion Nebula complex, these reflection nebulae are also associated with Orion's giant molecular cloud about 1,500 light-years away, but are dominated by the characteristic blue color of interstellar dust reflecting light from hot young stars. In this sharp color image a portion of the Orion Nebula appears along the bottom border with the cluster of reflection nebulae at picture center. NGC 1977 stretches across the field just below center, separated from NGC 1973 (above right) and NGC 1975 (above left) by dark regions laced with faint red emission from hydrogen atoms. Taken together, the dark regions suggest the region's popular moniker, the Running Man Nebula...

By Franz Lidz from NYT Science https://ift.tt/dMstkIc