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Showing posts with the label Alpha
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! ...
Look up this week and see a whole bunch of planets. Just after sunset, looking west (mostly), planets Mercury , Venus , Saturn , and Jupiter will all be visible to the unaided eye simultaneously. If you have a telescope, planets Uranus and Neptune can also be seen. In order up from the horizon, the lineup this week will be Venus (the brightest), Mercury , Saturn , Neptune, Uranus, and Jupiter (second brightest). It doesn't matter where on Earth you live because this early evening planet parade will be visible through clear skies all around the globe. The planets will appear to be nearly in a line because they all orbit the Sun in nearly the same plane: the ecliptic . The featured image shows a similar planet parade that occurred in 2022, captured over the Sydney Opera House in southern Australia . Although visible all week , the planets will be most easily seen together this weekend. from NASA https://ift.tt/A05tO4Q
Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city . With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The featured 18-hour exposure , taken from Bory Tucholskie , Poland covers a sky area several times the size of the full moon . Also known as the Seven Sisters and M45 , the Pleiades lies about 400 light years away toward the constellation of the Bull ( Taurus ). A common legend with a modern twist is that one of the brighter stars faded since the cluster was named, leaving only six of the sister stars visible to the unaided eye. The actual number of Pleiades stars visible, however, may be more or less than seven, depending on the darkness of the surrounding sky and t...
What if you saw your shadow on Mars and it wasn't human ? Then you might be the Opportunity rover exploring Mars. Opportunity explored the Red Planet from 2004 to 2018, finding evidence of ancient water , and sending breathtaking images across the inner Solar System . Pictured here in 2004, Opportunity looks opposite the Sun into Endurance Crater and sees its own shadow . Two wheels are visible on the lower left and right, while the floor and walls of the unusual crater are visible in the background. Caught in a dust storm in 2018 , Opportunity stopped responding, and NASA stopped trying to contact it in 2019 and declared the ground-breaking mission , originally planned for only 92 days, complete . from NASA https://ift.tt/KgYbCZ0

Twilight with Moon and Planets

Only two days after the February New Moon's annular eclipse of the Sun, a slender lunar crescent poses above the western horizon after sunset in this wintry twilight skyscape. Its nightside faintly illuminated by earthshine, the young Moon is joined by three bright planets in the mostly clear, early evening skies above the village of Kirazli, Turkiye. Inner planet Venus appears closest to the horizon. Near the beginning of its 2026 performance as planet Earth's evening star, brilliant Venus is seen through the warm sunset glare near picture center. Straight above Venus, innermost planet Mercury is easy to spot as it stands remarkably high above the horizon even as the twilight sky is growing dark. Outer planet Saturn , most distant of the naked-eye planets, is found just left of the Moon's sunlit crescent. from NASA https://ift.tt/rVQ48mX
"A ghost in the Milky Way…” says Christian Bertincourt, the astrophotographer behind this striking image of Barnard 93 (B93). The 93rd entry in Barnard’s Catalogue of Dark Nebula e, B93 lies within the Small Sagittarius Star Cloud ( Messier 24 ), where its darkness stands in stark contrast to bright stars and gas in the background. In some ways, B93 is really like a ghost , because it contains gas and dust that was dispersed by the deaths of stars , like supernovas . B93 appears as a dark void not because it is empty, but because its dust blocks the light emitted by more distant stars and glowing gas. Like other dark nebulas, some gas from B93 , if dense and massive enough, will eventually gravitationally condense to form new stars . If so, then once these stars ignite , B93 will transform from a dark ghost into a brilliant cradle of newborn stars. from NASA https://ift.tt/mOSVjbG

IC 2574: Coddington s Nebula

Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact, dwarf galaxy IC 2574 shows clear evidence of intense star forming activity in its telltale reddish regions of glowing hydrogen gas. Just as in spiral galaxies, the turbulent star-forming regions in IC 2574 are churned by stellar winds and supernova explosions spewing material into the galaxy's interstellar medium and triggering further star formation. A mere 12 million light-years distant, IC 2574 is part of the M81 group of galaxies, seen toward the northern constellation Ursa Major. Also known as Coddington's Nebula, the faint but intriguing island universe is about 50,000 light-years across, discovered by American astronomer Edwin Coddington in 1898. from NASA https://ift.tt/udcMthG
Cradled in red-glowing hydrogen gas, stars are being born in Orion. These stellar nurseries lie at the edge of the giant Orion molecular cloud complex , some 1,500 light-years away. This detailed view spans about 12 degrees across the center of the well-known constellation, with the Great Orion Nebula , the closest large star -forming region, visible toward the lower right. The deep mosaic also includes, near the top center, the Flame Nebula and the Horsehead Nebula . Image data acquired with a hydrogen-alpha filter adds other remarkable features to this wide-angle cosmic vista: pervasive tendrils of energized atomic hydrogen gas and portions of the surrounding Barnard's Loop . While the Orion Nebula and many stars in Orion are easy to see with the unaided eye, emission from the extensive interstellar gas is faint and much harder to record , even in telescopic views of the nebula-rich complex. from NASA https://ift.tt/PBA0YeI
Some comets are regular guests of our solar neighborhood; others come by only once, never to return. We won’t have another chance to see Comet C/2024 E1 (WierzchoÅ› ), which is currently making its way through the inner Solar System . The hyperbolic orbit of this comet indicates that it will likely become an interstellar traveler. Comet WierzchoÅ› is today near its closest approach to the Earth, passing roughly the same distance from the Earth as is the Sun . The featured 30-minute exposure was taken last week in Chile and shows a 5-degree long ion tail as well as three shorter dust tails . The green hue of the coma comes from the breakdown of dicarbon molecules by sunlight, but that process does not last long enough to also tinge the tails . On the far right lies a spiral galaxy far in the distance: NGC 300 . from NASA https://ift.tt/aXiwNK5
How is RXJ0528+2838 creating such shock waves? A recently discovered white dwarf star , the farther left of the two largest white spots, RXJ0528+2838 , was found 730 light-years away from Earth . Most stars, when done fusing nuclei in their cores for energy, become red giant stars, the cores of which live on as faint dense white dwarfs that slowly cool down for the rest of time. White dwarfs are so dense that the only thing that stops them from collapsing further is quantum mechanics . In about 5 billion years, our Sun will become a white dwarf , too. The featured image , obtained with the European Southern Observatory ’s Very Large Telescope , shows unexplained bow shocks around RXJ0528+2838, similar to the bow wave of water around a fast-moving ship. Astronomers don’t yet know what is powering these shocks , which have existed for at least 1,000 years. The red, green and blue colors represent trace amounts of glowing hydrogen , nitrogen and oxygen gas. from NASA https:/...
What would it be like to fly free in space? About 100 meters from the cargo bay of a space shuttle , Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured , was floating free in space. During Space Shuttle mission 41-B in 1984, McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "un tether ed space walk ". The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites . With a mass over 140 kilograms, an MMU is heavy on Earth , but, like everything, is weightless when drifting in orbit. The MMU was later replaced with the SAFER backpack propulsion unit. from NASA https://ift.tt/VwlHUOY

Roses are Red

Roses are red, nebulas are too, and this Valentine's gift is a stunning view! Pictured is a loving look at the Rosette Nebula ( NGC 2237 ): a cosmic bloom of bright young stars sitting atop a stem of glowing hot gas. The rose’s blue-white speckles are among the most luminous stars in the galaxy , with some burning millions of times brighter than the Sun. Their stellar winds sculpt the famed rose shape by pushing gas and dust away from the center. Though only a few million years old, these massive stars are already nearing the end of their lives , while dimmer stars embedded in the nebula will burn for billions of years to come. The vibrant red hue comes from hydrogen gas , ionized by the ultraviolet light from the young stars . The rose’s blue-white center is color-mapped to indicate the presence of similarly ionized oxygen. The Rosette Nebula reminds us of the beauty and transformation woven into the fabric of the universe. from NASA https://ift.tt/Uo6k2uy

NGC 147 and NGC 185

Dwarf galaxies NGC 147 (left) and NGC 185 stand side by side in this deep telescopic portrait. The two are not-often-imaged satellite galaxies of M31, the great spiral Andromeda Galaxy , some 2.5 million light-years away. Their separation on the sky, less than one degree across a pretty field of view toward the constellation Cassiopeia, translates to only about 35 thousand light-years at Andromeda's distance, but Andromeda itself is found well outside this frame. Brighter and more famous satellite galaxies of Andromeda, M32 and M110 , are seen much closer to the great spiral. NGC 147 and NGC 185 have been identified as binary galaxies, forming a gravitationally stable binary system. But recently discovered faint dwarf galaxy Cassiopeia II also seems to be part of their system, forming a gravitationally bound group within Andromeda's intriguing population of small satellite galaxies . from NASA https://ift.tt/HqDghxO