APOD: 2024 April 4 - Comet Pons-Brooks at 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. 2024 April 4 Comet Pons-Brooks at Night Image Credit &Copyright: Dan Bartlett` Explanation: In dark evening skies over June Lake,northern hemisphere, planet Earth,Comet 12P/Pons-Brooksstood just above the western horizon on March 30.Its twisted turbulent ion tail and diffuse greenish coma are capturedin this two degree wide telescopic field of view along with brightyellowish star Hamal also known asAlpha Arietis.Now Pons-Brooks has moved out of the northern night though, approachingperihelion on April 21.On April 8 you mightstill spot the comet in daytime skies.But to do it, you will have to stand in the path of totality andlook away from the spectacle of analluring solar corona and totally eclipsed Sun. NASA Coverage: Total Solar Eclipse of 2024 April 8 Tomorrow's picture: pixels in space <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation& Michigan Tech. U.

Astronomy Picture of the Day 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. 2024 April 5 The Solar Corona Unwrapped Image Credit &Copyright: Peter Ward(Barden Ridge Observatory) Explanation: Changes in thealluring solar coronaare detailed in thiscreative composite imagemapping the dynamic outer atmosphere of the Sun during two separate total solar eclipses.Unwrapped from the complete circle of the eclipsed Sun's edgeto a rectangle and mirrored, the entire solar corona is shownduring the2017 eclipse (bottom)seen from Jackson Hole, Wyoming, and the2023 eclipse from Exmouth, Western Australia.While the 2017 eclipse was near a minimum in theSun's 11 year activity cycle,the 2023 eclipse was closer to solar maximum.The 2023 solar corona hints at the dramatically different characterof the active Sun,with many streamers and pinkish prominences arising along the solar limb.Of course, the solar corona is only easily visible to the eyewhile standing in the shadow of the Moon. NASA Coverage: Total Solar Eclipse of 2024 April 8 Tomorrow's picture: M51 unwound <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility...

Astronomy Picture of the Day 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. 2024 April 4 Comet Pons-Brooks at Night Image Credit &Copyright: Dan Bartlett` Explanation: In dark evening skies over June Lake,northern hemisphere, planet Earth,Comet 12P/Pons-Brooksstood just above the western horizon on March 30.Its twisted turbulent ion tail and diffuse greenish coma are capturedin this two degree wide telescopic field of view along with brightyellowish star Hamal also known asAlpha Arietis.Now Pons-Brooks has moved out of the northern night though, approachingperihelion on April 21.On April 8 you mightstill spot the comet in daytime skies.But to do it, you will have to stand in the path of totality andlook away from the spectacle of analluring solar corona and totally eclipsed Sun. NASA Coverage: Total Solar Eclipse of 2024 April 8 Tomorrow's picture: pixels in space <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation& Michigan Tech. U.

APOD: 2024 March 29 - Galileo's Europa 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. 2024 March 29 Galileo's Europa Image Credit: NASA,JPL-Caltech,SETI Institute,Cynthia Phillips,Marty Valenti Explanation: Looping through the Jovian system in the late 1990s, theGalileo spacecraftrecorded stunning views of Europa and uncoveredevidence that the moon's icy surface likely hidesa deep, global ocean.Galileo's Europa image data has beenremastered here, with improved calibrations to produce acolor image approximating what the human eye might see.Europa's long curving fractureshint at the subsurface liquid water. The tidal flexing the large moon experiencesin its elliptical orbitaround Jupiter supplies the energy to keep the ocean liquid.But moretantalizing is the possibilitythat even in theabsence of sunlight that process could also supply the energy tosupport life,making Europaone of the best places to look for lifebeyond Earth.The Juno spacecraft currently in Jovian orbithas also made repeated flybys of the water world,returning images along with data exploringEuropa's habitability.This October will see the launch of the NASA'sEuropa Clipperon a voyage ofexploration.The spacecraft will make nearly 50 flybys,approaching to within 25 kilometers of Europa's icy surface. Tomorrow's picture: Ptolemy's astronomy <| Archive| Submissions | Index| Search|...

Astronomy Picture of the Day 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. 2024 March 30 Medieval Astronomy from Melk Abbey Image Credit: Paul Beck (Univ. Vienna),Georg Zotti (ViennaInst. Arch. Science)Copyright: Library of Melk Abbey, Frag. 229 Explanation: Discovered by accident, this manuscript pageprovides graphical insight to astronomy inmedieval times, before theRenaissance and the influence ofNicolaus Copernicus,Tycho de Brahe,Johannes Kepler, andGalileo.The intriguing page is from lecture noteson astronomy compiled by the monk Magister Wolfgang de Styriabefore the year 1490.The top panels clearly illustrate the necessary geometry for alunar (left) and solar eclipse in the Earth-centeredPtolemaic system.At lower left is a diagram of the Ptolemaic view of theSolar Systemwith text at the upper right to explain the movementof the planets according toPtolemy's geocentricmodel.At the lower right is a chart to calculate thedateof Easter Sunday in theJulian calendar.The illustrated manuscript page was found at historicMelk Abbey in Austria. Tomorrow's picture: eclipse below <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation&...

APOD: 2024 March 28 - Millions of Stars in Omega Centauri 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. 2024 March 28 Millions of Stars in Omega Centauri Image Credit &Copyright:Massimo Di Fuscoand Mirco Turra Explanation: Globular star clusterOmega Centauri,also known as NGC 5139, is 15,000 light-years away.The cluster is packed with about 10 millionstars much older than the Sun within a volume about 150 light-years indiameter.It's the largest and brightest of 200 or so knownglobular clusters that roam the halo of our Milky Way galaxy.Though most star clusters consist of stars with the same age andcomposition, the enigmatic Omega Cen exhibits the presence ofdifferentstellar populations with a spread of ages and chemical abundances.In fact,Omega Cen may betheremnantcore of a small galaxy merging with the Milky Way.With a yellowish hue,Omega Centauri's red giant stars are easy to pick out in thissharp, color telescopic view. Tomorrow's picture: Galileo's Europa <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation& Michigan Tech....

Astronomy Picture of the Day 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. 2024 March 29 Galileo's Europa Image Credit: NASA,JPL-Caltech,SETI Institute,Cynthia Phillips,Marty Valenti Explanation: Looping through the Jovian system in the late 1990s, theGalileo spacecraftrecorded stunning views of Europa and uncoveredevidence that the moon's icy surface likely hidesa deep, global ocean.Galileo's Europa image data has beenremastered here, with improved calibrations to produce acolor image approximating what the human eye might see.Europa's long curving fractureshint at the subsurface liquid water. The tidal flexing the large moon experiencesin its elliptical orbitaround Jupiter supplies the energy to keep the ocean liquid.But moretantalizing is the possibilitythat even in theabsence of sunlight that process could also supply the energy tosupport life,making Europaone of the best places to look for lifebeyond Earth.The Juno spacecraft currently in Jovian orbithas also made repeated flybys of the water world,returning images along with data exploringEuropa's habitability.This October will see the launch of the NASA'sEuropa Clipperon a voyage ofexploration.The spacecraft will make nearly 50 flybys,approaching to within 25 kilometers of Europa's icy surface. Tomorrow's picture: Ptolemy's astronomy <| Archive| Submissions | Index| Search| Calendar| RSS|...

Astronomy Picture of the Day 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. 2024 March 28 Millions of Stars in Omega Centauri Image Credit &Copyright:Massimo Di Fuscoand Mirco Turra Explanation: Globular star clusterOmega Centauri,also known as NGC 5139, is 15,000 light-years away.The cluster is packed with about 10 millionstars much older than the Sun within a volume about 150 light-years indiameter.It's the largest and brightest of 200 or so knownglobular clusters that roam the halo of our Milky Way galaxy.Though most star clusters consist of stars with the same age andcomposition, the enigmatic Omega Cen exhibits the presence ofdifferentstellar populations with a spread of ages and chemical abundances.In fact,Omega Cen may betheremnantcore of a small galaxy merging with the Milky Way.With a yellowish hue,Omega Centauri's red giant stars are easy to pick out in thissharp, color telescopic view. Tomorrow's picture: pixels in space <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation& Michigan Tech. U.

Astronomy Picture of the Day 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. 2024 March 22 Phobos: Moon over Mars Image Credit: NASA,ESA,Zolt Levay (STScI)-Acknowledgment:J.Bell (ASU) andM.Wolff (SSI) Explanation: A tiny moon with a scary name,Phobos emerges from behindthe Red Planet in this timelapse sequence from the Earth-orbitingHubble Space Telescope.Over 22 minutes the 13 separate exposures werecaptured near the 2016 closestapproach of Mars to planet Earth.Martians have to look to the westto watch Phobos rise, though.The small moon is closer to itsparent planet than any othermoon in the Solar System, about 3,700 miles (6,000 kilometers)above the Martian surface.It completes one orbit in just 7 hours and 39 minutes.That's faster than a Mars rotation, which corresponds toabout 24 hours and 40 minutes.So on Mars, Phobos can be seen to rise abovethe western horizon 3 times a day.Still, Phobos is doomed. Tomorrow's picture: Ares 3 Landing Site <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation& Michigan Tech. U.

APOD: 2024 March 21 - The Leo Trio 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. 2024 March 21 The Leo Trio Image Credit &Copyright: Steve Cannistra Explanation: This popular group leaps into the early evening sky around the Marchequinox andthe northern hemisphere spring. Famous as theLeo Triplet,the three magnificent galaxies found in the prominentconstellation Leogather here in one astronomical field of view.Crowd pleasers when imaged with even modesttelescopes, they can be introduced individually asNGC 3628 (left), M66 (bottom right), and M65 (top).All three are largespiral galaxies buttend to look dissimilar, because their galactic disks aretilted at different angles to our line of sight.NGC 3628,also known as the Hamburger Galaxy,is temptingly seen edge-on, with obscuring dust lanescutting across its puffy galactic plane.The disksof M66andM65 areboth inclined enough to show off their spiral structure. Gravitational interactions between galaxies in the grouphave left telltale signs, including the tidal tails andwarped, inflated disk of NGC 3628 and the drawn out spiral arms of M66.This gorgeous viewof the region spans over 1 degree (two full moons) on the skyin a frame that covers over half a million light-years at...

Astronomy Picture of the Day 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. 2024 March 21 The Leo Trio Image Credit &Copyright: Steve Cannistra Explanation: This popular group leaps into the early evening sky around the Marchequinox andthe northern hemisphere spring. Famous as theLeo Triplet,the three magnificent galaxies found in the prominentconstellation Leogather here in one astronomical field of view.Crowd pleasers when imaged with even modesttelescopes, they can be introduced individually asNGC 3628 (left), M66 (bottom right), and M65 (top).All three are largespiral galaxies buttend to look dissimilar, because their galactic disks aretilted at different angles to our line of sight.NGC 3628,also known as the Hamburger Galaxy,is temptingly seen edge-on, with obscuring dust lanescutting across its puffy galactic plane.The disksof M66andM65 areboth inclined enough to show off their spiral structure. Gravitational interactions between galaxies in the grouphave left telltale signs, including the tidal tails andwarped, inflated disk of NGC 3628 and the drawn out spiral arms of M66.This gorgeous viewof the region spans over 1 degree (two full moons) on the skyin a frame that covers over half a million light-years at thetrio's estimated distance...

Astronomy Picture of the Day 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. 2024 March 16 ELT and the Milky Way Image Credit &License:European Southern Observatory -Courtesy: Jens Scheidtmann Explanation: The southern winterMilky Way sprawlsacross this night skyscape.Looking due south, thewebcam viewwas recorded near local midnighton March 11 in dry, dark skies over the central Chilean Atacama desert.Seen below the graceful arc of diffuse starlightare satellite galaxies of the mighty Milky Way, also known asthe Large and SmallMagellanic clouds.In the foreground is the site of the European SouthernObservatory's 40-metre-classExtremely Large Telescope(ELT).Under construction at the 3000 metre summit ofCerro Armazones, the ELT ison track to become planet Earth's biggest Eye on the Sky. Tomorrow's picture: when galaxies collide <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility NoticesA service of:ASD atNASA /GSFC,NASA Science Activation& Michigan Tech. U.

APOD: 2024 March 15 - Portrait of NGC 1055 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. 2024 March 15 Portrait of NGC 1055 Image Credit &Copyright: Dave Doctor Explanation: Big, beautiful spiral galaxy NGC 1055 is a dominant member ofa small galaxy groupa mere 60 million light-years away towardthe aquatically intimidatingconstellation Cetus.Seen edge-on, the island universe spans over 100,000 light-years,a little larger than ourown Milky Way galaxy.The colorful, spiky stars decorating this cosmicportrait of NGC 1055are in the foreground, well within the Milky Way.But the telltale pinkish star formingregions are scattered throughwinding dust lanes along the distant galaxy's thin disk.With a smattering of even more distant background galaxies, thedeep image also reveals a boxy halo that extendsfar above and below the central bulge and disk of NGC 1055.The halo itself is laced with faint, narrow structures,and could represent the mixed and spread outdebris from a satellite galaxydisrupted bythe larger spiral some10 billion years ago. Tomorrow's picture: an extremely large telescope <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific...

Astronomy Picture of the Day 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. 2024 March 15 Portrait of NGC 1055 Image Credit &Copyright: Dave Doctor Explanation: Big, beautiful spiral galaxy NGC 1055 is a dominant member ofa small galaxy groupa mere 60 million light-years away towardthe aquatically intimidatingconstellation Cetus.Seen edge-on, the island universe spans over 100,000 light-years,a little larger than ourown Milky Way galaxy.The colorful, spiky stars decorating this cosmicportrait of NGC 1055are in the foreground, well within the Milky Way.But the telltale pinkish star formingregions are scattered throughwinding dust lanes along the distant galaxy's thin disk.With a smattering of even more distant background galaxies, thedeep image also reveals a boxy halo that extendsfar above and below the central bulge and disk of NGC 1055.The halo itself is laced with faint, narrow structures,and could represent the mixed and spread outdebris from a satellite galaxydisrupted bythe larger spiral some10 billion years ago. Tomorrow's picture: an extremely large telescope <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Amber StraughnSpecific rights apply.NASA Web Privacy,Accessibility...

APOD: 2024 March 14 - Moon Pi and Mountain Shadow 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. 2024 March 14 Moon Pi and Mountain Shadow Image Credit & Copyright:Daniel Lopez(El Cielo de Canarias) Explanation: What phase of the Moon is 3.14 radians from the Sun?The Full Moon, of course.Even though theMoon might look fullfor several days, the Moon is truly at its full phase when it isPi radians(aka 180 degrees) from the Sun in ecliptic longitude.That's opposite the Sun in planet Earth's sky.Rising as the Sun set on March 9, 2020, only an hour or so after the moment ofits full phase, this orange tinted andslightly flattenedMoon still looked full.It was photographed opposite the setting Sun from Teide National Parkon the Canary Island of Tenerife.Also opposite the setting Sun, seen from near the Teide volcano peakabout 3,500 meters above sea level, is the mountain's risingtriangular shadowextending into Earth's dense atmosphere.Below the distant ridge line on the left are thewhite telescope domes ofTeide Observatory.Again Pi radians from the Sun, on March 25 the Full Moon will dimslightly as it glides through Earth's outer shadow in...