APOD: 2022 March 11 - When Rainbows Smile Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 11 When Rainbows Smile Image Credit &Copyright:Marcella Giulia Pace Explanation: Want to see a rainbow smile?Look near the zenith (straight up) when the sun is low in thesky and you might.This example of an ice haloknown as a circumzenithal arc wascaptured above a palm tree top from Ragusa, Sicily on February 24.The vividly colorful arcs are often called smiling rainbowsbecause of their upside down curvature and colors.For circumzenithal arcsthezenith isat the center and red is on the outside, compared to rainbows whose arcsbend toward the horizonafter a downpour.True rainbows are formed by water droplets refractingthe sunlight to produce a spectrum of colors,though.Circumzenithal arcs are the product ofrefraction and reflectionin flat hexagonal ice crystals, like the ice crystals that create sundogs,formed in high thin clouds. Tomorrow's picture: Point Reyes Milky Way <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan Tech....

Globular star cluster 47 Tucanae is a jewel of the southern sky.

APOD: 2022 March 9 - A Flower Shaped Rock on Mars Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 9 A Flower-Shaped Rock on Mars Image Credit: NASA,JPL-Caltech,MSSS Explanation: It is one of the more unusual rocks yet found on Mars.Smaller than a penny, the rock has several appendages that make it look, to some, like a flower.Although it would be a major discovery if the rock was truly a fossilized ancient Martian flower, there are less spectacular -- and currently preferred -- explanations for its unusual structure. One theory that has emerged is that the rock is a type of concretion created by minerals deposited by water in cracks or divisions in existing rock.These concretions can be compacted together, can be harder and denser than surrounding rock, and can remain even after the surrounding rock erodes away. The flower structure may also be caused by crystal clusters.The small rock, named Blackthorn Salt, has similarities to previously imaged Martian pebbles.The featured image was taken by the Curiosity rover on Mars in late February. Scientists will continue to study data and images taken of...

APOD: 2022 March 8 - Moon in Inverted Colors Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 8 Moon in Inverted Colors Image Credit & Copyright: Dawid Glawdzin Explanation: Which moon is this?It's Earth's moon -- but in inverted colors.Here, the pixel values corresponding to light and dark areas have been translated in reverse, or inverted, producing a false-color representation reminiscent of a black and white photographic negative. However, this is an inverted color image -- where the muted colors of the moon are real but digitally exaggerated before inversion. Normally bright rays from the large crater Tycho dominate the southern (bottom) features as easily followed dark green lines emanating from the 85-kilometer diameter impact site. Normally dark lunar mare appear light and silvery. The image was acquired in Southend-on-Sea, England, UK. Historically, astronomical images recorded on photographic plates were directly examined on inverted-color negatives because it helped the eye pick out faint details. Tomorrow's picture: martian rock flower <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific...

APOD: 2022 March 7 - A Lion in Orion Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 7 A Lion in Orion Image Credit & Copyright: Maroun Mahfoud Explanation: Yes, but can you see the lion?A deep exposure shows the famous dark indentation that looks like ahorse's head, visible just left and below center, and known unsurprisingly as the Horsehead Nebula. The Horsehead Nebula (Barnard 33) is part of a vast complex of dark absorbingdust and brightglowing gas. To bring out details of the Horsehead's pasture, an astrophotographer artistically combined light accumulated for over 20 hours in hydrogen (orange), oxygen (blue), and sulfur (green).The resulting spectacular picturecaptured from Raachine,Lebanon,details an intricate tapestry of gaseous wisps and dust-laden filaments that were created andsculpted over eons by stellar winds andancient supernovas. The featured composition brings up another pareidolic animal icon -- that of a lion's head -- in the expansive orange colored gas above the horse's head. The Flame Nebula is visible just to the left of the Horsehead. The Horsehead Nebula lies 1,500 light years distant towards the constellation of Orion. Tomorrow's picture: oddly...

APOD: 2022 March 6 - Venus and the Triply Ultraviolet Sun Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 6 Venus and the Triply Ultraviolet Sun Image Credit: NASA/SDO & the AIA, EVE, and HMI teams; Digital Composition: Peter L. Dove Explanation: This was a very unusual type of solar eclipse. Typically, it is the Earth's Moon that eclipses the Sun. In 2012, though, the planet Venus took a turn. Like a solar eclipse by the Moon, the phase of Venus became a continually thinner crescent as Venus became increasingly better aligned with the Sun. Eventually the alignment became perfect and the phase of Venus dropped to zero. The dark spot of Venus crossed our parent star. The situation could technically be labeled a Venusian annular eclipse with an extraordinarily large ring of fire. Pictured here during the occultation, the Sun was imaged in three colors of ultraviolet light by the Earth-orbiting Solar Dynamics Observatory, with the dark region toward the right corresponding to a coronal hole.Hours later, as Venus continued in its orbit, a slight crescent phase appeared again. The next Venusian...

APOD: 2022 March 5 - Interstellar Comet 2I Borisov Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 5 Interstellar Comet 2I Borisov NASA, ESA, and D.Jewitt (UCLA) et al. Explanation: From somewhere elsein the Milky Way galaxy,Comet 2I/Borisovwas just visiting the Solar System.Discovered by amateur astronomer Gennady Borisovon August 30, 2019, the first known interstellar cometis seen in these two Hubble Space Telescope imagesfrom November and December 2019.On the left, a distant background galaxy near the line-of-sight toBorisov is blurred asHubbletracked the speeding comet and dust tail about327 million kilometers from Earth.At right, 2I/Borisov appears shortly after perihelion, its closestapproach to Sun.European Southern Observatoryobservations indicatethat this comet may never have passed closeto any star before its 2019 perihelion passage.Borisov's closestapproach to our fair planet, a distance of about 290 millionkilometers, came on December 28, 2019.Even though Hubble's sharp images don't resolve the comet's nucleus,they did lead to estimates of less than 1 kilometer for its diameter. Tomorrow's picture: triple Sun holes <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official:...

APOD: 2022 March 4 - The Multiwavelength Crab Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 4 The Multiwavelength Crab NASA,ESA,G. Dubner(IAFE, CONICET-University of Buenos Aires) et al.;A. Loll et al.;T. Temim et al.;F. Seward et al.;VLA/NRAO/AUI/NSF;Chandra/CXC;Spitzer/JPL-Caltech;XMM-Newton/ESA;Hubble/STScI Explanation: The Crab Nebula is cataloged as M1, the first object onCharlesMessier's famous list of things which are not comets.In fact, theCrabis now known to be asupernovaremnant, expanding debris from massive star's death explosion,witnessed on planet Earth in 1054 AD.Thisbrave new image offers a 21st centuryview of the Crab Nebula by presenting image data from across theelectromagneticspectrum as wavelengths of visible light.From space, Chandra (X-ray)XMM-Newton (ultraviolet),Hubble (visible), andSpitzer (infrared),data are in purple, blue, green, and yellow hues.From the ground,Very Large Arrayradio wavelength data is shown in red.One of the most exotic objects known to modern astronomers,the Crab Pulsar,a neutron star spinning 30 times a second,is the bright spot near picture center.Like a cosmic dynamo,this collapsed remnant of the stellar corepowers the Crab's emission across the electromagnetic spectrum.Spanning about 12 light-years, the Crab Nebula is6,500 light-years away in the constellationTaurus. Tomorrow's picture: from somewhere else <| Archive|...

APOD: 2022 March 3 - Spiral Galaxy NGC 2841 Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 3 Spiral Galaxy NGC 2841 Image Credit &Copyright: Vitali Pelenjow Explanation: A mere 46 million light-years distant, spiral galaxy NGC 2841can be found in the northern constellation ofUrsa Major.This deep viewof the gorgeousisland universewas captured during32 clear nights in November, December 2021 and January 2022.It shows off a striking yellow nucleus, galactic disk, and faint outerregions. Dust lanes, small star-forming regions, and young star clustersare embedded in the patchy, tightlywoundspiral arms.In contrast, many other spiralsexhibit grand, sweeping arms with large star-forming regions. NGC 2841 hasa diameter of over 150,000 light-years, even larger thanour own Milky Way.X-ray imagessuggest that resulting winds and stellar explosions createplumes of hot gas extending into a halo around NGC 2841. Tomorrow's picture: multiwavelength crab <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan Tech. U.

APOD: 2022 March 2 - Record Prominence Imaged by Solar Orbiter Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 2 Record Prominence Imaged by Solar Orbiter Image Credit: Solar Orbiter, EUI Team, ESA & NASA; h/t: Bum-Suk Yeom Explanation: What's happened to our Sun? Last month, it produced the largest prominence ever imaged together with a complete solar disk.The record image, featured, was captured in ultraviolet light by the Sun-orbiting Solar Orbiter spacecraft.A quiescent solar prominence is a cloud of hot gas held above the Sun's surface by the Sun's magnetic field. This solar prominence was huge -- spanning a length rivaling the diameter of the Sun itself.Solar prominences may erupt unpredictably and expel hot gas into the Solar System via a Coronal Mass Ejection (CME). When a CME strikes the Earth and its magnetosphere, bright auroras may occur.This prominence did produce a CME, but it was directed well away from the Earth.Although surely related to the Sun's changing magnetic field, the energy mechanism that creates and sustains a solar prominence remains a topic of research. Tomorrow's picture: spiral galaxy NGC 2841 <|...

APOD: 2022 March 1 - Dueling Bands in the Night Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 March 1 Dueling Bands in the Night Image Credit & Copyright: Jeff Dai(TWAN) Explanation: What are these two bands in the sky?The more commonly seen band is the one on the right and is the central band of our Milky Way galaxy.Our Sun orbits in the disk of this spiral galaxy, so that from inside, this disk appears as a band of comparable brightness all the way around the sky.The Milky Way band can also be seen all year -- if out away from city lights. The less commonly seem band, on the left, is zodiacal light -- sunlight reflected from dust orbiting the Sun in our Solar System. Zodiacal light is brightest near the Sun and so is best seen just before sunrise or just after sunset. On some evenings in the north, particularly during the months of March and April, this ribbon of zodiacal light can appear quite prominent after sunset. It was determined only this century that zodiacal dust was mostly expelled by...

You don't have to look through a telescope to know where it's pointing.

APOD: 2022 February 27 - Earthrise 1: Historic Image Remastered Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 27 Earthrise 1: Historic Image Remastered Image Credit: NASA, Apollo 8 Crew, Bill Anders; Processing and License: Jim Weigang Explanation: "Oh my God! Look at that picture over there! Here's the Earth coming up. Wow is that pretty!"Soon after that pronouncement, about 53 years ago, one of the most famous images ever taken was snapped from the orbit of the Moon.Now known as "Earthrise", the iconic image shows the Earth rising above the limb of the Moon, as taken by the crew of Apollo 8. But the well-known Earthrise image was actually the second image taken of the Earth rising above the lunar limb -- it was just the first in color. With modern digital technology, however, the real first Earthrise image -- originally in black and white -- has now been remastered to have the combined resolution and color of the first three images. Behold! The featured image is a close-up of the picture that Apollo 8 astronaut Bill Anders was talking about.Thanks to...

APOD: 2022 February 26 - Nearby Spiral Galaxy NGC 4945 Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 26 Nearby Spiral Galaxy NGC 4945 Image Credit &Copyright: Dietmar Hager,Eric Benson Explanation: Large spiral galaxy NGC 4945 is seen nearlyedge-onin this cosmic galaxy close-up.It's almost the size of ourMilky Way Galaxy.NGC 4945's own dusty disk, young blue star clusters, and pink starforming regions stand out in the colorful telescopic frame.About 13 million light-years distant toward theexpansivesouthern constellationCentaurus, NGC 4945 is only about six times farther away than Andromeda,the nearest large spiral galaxy to the Milky Way.Though this galaxy's central region is largely hidden fromview for optical telescopes, X-ray and infrared observations indicatesignificanthigh energy emission and star formation in the coreof NGC 4945.Its obscured but active nucleus qualifies the gorgeous islanduniverse as a Seyfert galaxyand home to a central supermassive black hole. Tomorrow's picture: really famous picture -- remastered <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan...

APOD: 2022 February 25 - Perseverance Sol 354 Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 25 Perseverance Sol 354 Image Credit: NASA, JPL-Caltech, Processing;Kenneth Kremer Explanation: This Navcam mosaic fromPerseverance looks outover the car-sized rover's deck, across the floor of Jezerocrater on Mars.Frames used to construct the mosaic viewwere captured on mission sol 354.That corresponds to Earth calendar date February 17, 2022, nearlyone Earth year after the rover's landing.With a mass of over 1,000 kilograms, six-wheeledPerseverance is the heaviest rover totouch down on Mars.During its first year of explorationthe rover has collected six (so far)rock core samplesfor later return to planet Earth,served as the base stationfor Ingenuity, the first helicopter on Mars,andtested MOXIE(Mars Oxygen In-Situ Resource Utilization Experiment),converting some of the Red Planet’s thin, carbon dioxide-rich atmosphereinto oxygen. Tomorrow's picture: big space swirl <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan Tech. U.

APOD: 2022 February 24 - Beautiful Albireo AB Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 24 Beautiful Albireo AB Image Credit &Copyright: Robert Eder Explanation: Beta Cygniis a single bright star to the naked eye.About 420 light-years awayit marks the foot of the Northern Cross, famous asterism inthe constellation Cygnus.But a view through the eyepiece of a small telescope will transform itinto a beautiful double star, atreasure of the night skyin blue and gold.Beta Cygni isalso known as Albireo,designated Albireo AB to indicate its two bright component stars.Their visually striking color difference is illustratedin this telescopic snapshot,along with their associatedvisible spectrumof starlight shown in insets to the right.Albireo A, top inset, shows the spectrum of a K-type giant star, cooler thanthe Sun and emitting most of its energy at yellow and red wavelengths.Below, Albireo B has the spectrum of a main sequence star much hotterthan the Sun, emitting more energy in blue and violet.Albireo Ais known to be a binary star, two stars together orbiting acommon center of mass, though the two stars are too close togetherto be seen separately with a...

APOD: 2022 February 23 - Orion over Green Bank Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 23 Orion over Green Bank Image Credit & Copyright: Dave Green Explanation: What will the huge Green Bank Telescope discover tonight?Pictured, the Robert C. Byrd Green Bank Telescope (GBT) on the lower right is the largest fully-pointable single-dish radio telescope in the world.With a central dish larger than a football field, the GBT is nestled in the hills of West Virginia, USA in a radio quiet zone where the use of cell phones, WiFi emitters, and even microwave ovens are limited.The GBT explores our universe not only during the night -- but during the day, too, since the daytime sky is typically dark in radio waves. Taken in late January, the featured image was planned for months to get the setting location of Orion just right. The image is a composite of a foreground shot taken over a kilometer away from the GBT, and a background shot built up of long exposures during the previous night.The deep background image of Orion is fitting because the GBT...

APOD: 2022 February 22 - Illustration: An Early Quasar Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 22 Illustration: An Early Quasar Illustration Credit & License: ESO, M. Kornmesser Explanation: What did the first quasars look like? The nearest quasars are now known to involve supermassive black holes in the centers of active galaxies. Gas and dust that falls toward a quasar glows brightly, sometimes outglowing the entire home galaxy. The quasars that formed in the first billion years of the universe are more mysterious, though.Featured, recent data has enabled an artist's impression of an early-universe quasar as it might have been: centered on a massive black hole, surrounded by sheets of gas and an accretion disk, and expelling a powerful jet.Quasars are among the most distant objects we see and give humanity unique information about the early and intervening universe.The oldest quasars currently known are seen at just short of redshift 8 -- only 700 million years after the Big Bang -- when the universe was only a few percent of its current age. Tomorrow's picture: Green Orion <| Archive| Submissions |...

APOD: 2022 February 21 - Barred Spiral Galaxy NGC 6217 Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 21 Barred Spiral Galaxy NGC 6217 Image Credit: NASA,ESA, and theHubble SM4 ERO Team Explanation: Many spiral galaxies have bars across their centers. Even our ownMilky Way Galaxy is thought to have amodest central bar.Prominently barred spiral galaxy NGC 6217,featured here, was captured in spectacular detail in this image taken by the Advanced Camera for Surveys on the orbitingHubble Space Telescope in 2009.Visible are dark filamentarydust lanes, youngclusters of bright blue stars, redemission nebulas of glowing hydrogen gas,a long bar of stars across the center, and a brightactive nucleusthat likely houses a supermassiveblack hole. Light takes about 60 million years to reach us fromNGC 6217, which spans about 30,000light years across and can be found toward theconstellation of the Little Bear(Ursa Minor). APOD in world languages: Arabic,Bulgarian,Catalan,Chinese (Beijing),Chinese (Taiwan),Croatian, Czech,Dutch,French, French (Canada),German, Hebrew, Indonesian,Japanese,Korean, Montenegrin, Polish,Russian,Serbian, Slovenian, Spanish,Taiwanese, Turkish,Turkish,and Ukrainian Tomorrow's picture: quasar illustrated <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA...

APOD: 2022 February 20 - Aurora Over White Dome Geyser Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 February 20 Aurora Over White Dome Geyser Image Credit & Copyright: Robert Howell Explanation: Sometimes both heaven and Earth erupt.Colorful auroras erupted unexpectedly a few years ago, with green aurora appearing near the horizon and brilliant bands of red aurora blooming high overhead. A bright Moon lit the foreground of this picturesque scene, while familiar stars could be seen far in the distance. With planning, the careful astrophotographer shot this image mosaic in the field of White Dome Geyser in Yellowstone National Park in the western USA.Sure enough, just after midnight, White Dome erupted -- spraying a stream of water and vapor many meters into the air.Geyser water is heated to steam by scalding magma several kilometers below, and rises through rock cracks to the surface.About half of all known geysers occur in Yellowstone National Park.Although the geomagnetic storm that caused the auroras subsided within a day, eruptions of White Dome Geyser continue about every 30 minutes. Tomorrow's picture: barred spiral <| Archive| Submissions | Index|...