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Astronomy Picture of the Day
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 November 6
Red Aurora over Italy
Image Credit & Copyright: Giorgia Hofer
Explanation:
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.
Aurora Album:
Selected images sent in to APOD
Tomorrow's picture: devil on mars
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
30
Astronomy Picture of the Day
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 November 6
Red Aurora over Italy
Image Credit & Copyright: Giorgia Hofer
Explanation:
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.
Aurora Album:
Selected images sent in to APOD
Tomorrow's picture: devil on mars
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
31
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 October 18
Dust and the Western Veil Nebula
**Image Credit & Copyright: ** [Jiang Wu](mailto: wujiang0910 at gmail dot
com)
Explanation:
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.
Tomorrow's picture:open space
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
32
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 October 18
Dust and the Western Veil Nebula
**Image Credit & Copyright: ** [Jiang Wu](mailto: wujiang0910 at gmail dot
com)
Explanation:
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.
Tomorrow's picture:open space
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
33
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 October 16
Eclipse Rings
**Image Credit & Copyright: ** Jerry Zhang (left), Baolong Chen (photographer) & Amber Zhang (right)
Explanation: She knew everything but the question. She was well aware that there would be a complete [annular eclipse](https://science.nasa.gov/eclipses/future-eclipses/eclipse-2023/where- when/) 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".
Album: Selected eclipse images sent in to APOD Tomorrow's picture:dust rings
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
34
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 October 16
Eclipse Rings
**Image Credit & Copyright: ** Jerry Zhang (left), Baolong Chen (photographer) & Amber Zhang (right)
Explanation: She knew everything but the question. She was well aware that there would be a complete [annular eclipse](https://science.nasa.gov/eclipses/future-eclipses/eclipse-2023/where- when/) 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".
Album: Selected eclipse images sent in to APOD Tomorrow's picture:dust rings
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
35
Astronomy Picture of the Day
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 October 2
Sprite Lightning in High Definition
Image Credit & Copyright: Nicolas Escurat
Explanation: Sometimes lightning occurs out near space. One such lightning type is red sprite lightning, which has only been photographed and studied on Earth over the past 25 years. The origins of all types of lightning remain topics for research, and scientists are still trying to figure out why red sprite lightning occurs at all. Research has shown that following a powerful positive cloud-to-ground lightning strike, red sprites may start as 100-meter balls of ionized air that shoot down from about 80-km high at 10 percent the speed of light. They are quickly followed by a group of upward streaking ionized balls. Featured here is an extraordinarily high- resolution image of a group of red sprites. This image is a single frame lasting only 1/25th of a second from a video taken above Castelnaud Castle in Dordogne, France, about three weeks ago. The sprites quickly vanished -- no sprites were visible even on the very next video frame.
Tomorrow's picture:eye in the sky
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
36
Astronomy Picture of the Day
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 October 2
Sprite Lightning in High Definition
Image Credit & Copyright: Nicolas Escurat
Explanation: Sometimes lightning occurs out near space. One such lightning type is red sprite lightning, which has only been photographed and studied on Earth over the past 25 years. The origins of all types of lightning remain topics for research, and scientists are still trying to figure out why red sprite lightning occurs at all. Research has shown that following a powerful positive cloud-to-ground lightning strike, red sprites may start as 100-meter balls of ionized air that shoot down from about 80-km high at 10 percent the speed of light. They are quickly followed by a group of upward streaking ionized balls. Featured here is an extraordinarily high- resolution image of a group of red sprites. This image is a single frame lasting only 1/25th of a second from a video taken above Castelnaud Castle in Dordogne, France, about three weeks ago. The sprites quickly vanished -- no sprites were visible even on the very next video frame.
Tomorrow's picture:eye in the sky
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
37
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 September 29
Back from Bennu
Image Credit: NASA/Keegan Barber
Explanation: Back from asteroid 101955 Bennu, a 110-pound, 31-inch wide sample return capsule rests in a desert on planet Earth in this photo, taken at the Department of Defense Utah Test and Training Range near Salt Lake City last Sunday, September 24. Dropped off by the OSIRIS-Rex spacecraft, the capsule looks charred from the extreme temperatures experienced during its blistering descent through Earth's dense atmosphere. OSIRIS-Rex began its home-ward journey from Bennu in May of 2021. Delivered to NASA’s Johnson Space Center in Houston on September 25, the capsule's canister is expected to contain an uncontaminated sample of about a half pound (250 grams) of Bennu's loosely packed regolith. Working in a new laboratory designed for the OSIRIS-REx mission, scientists and engineers will complete the canister disassembly process, and plan to unveil the sample of the near-Earth asteroid in a broadcast event on October 11.
Tomorrow's picture: shine on
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
38
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 September 29
Back from Bennu
Image Credit: NASA/Keegan Barber
Explanation: Back from asteroid 101955 Bennu, a 110-pound, 31-inch wide sample return capsule rests in a desert on planet Earth in this photo, taken at the Department of Defense Utah Test and Training Range near Salt Lake City last Sunday, September 24. Dropped off by the OSIRIS-Rex spacecraft, the capsule looks charred from the extreme temperatures experienced during its blistering descent through Earth's dense atmosphere. OSIRIS-Rex began its home-ward journey from Bennu in May of 2021. Delivered to NASA’s Johnson Space Center in Houston on September 25, the capsule's canister is expected to contain an uncontaminated sample of about a half pound (250 grams) of Bennu's loosely packed regolith. Working in a new laboratory designed for the OSIRIS-REx mission, scientists and engineers will complete the canister disassembly process, and plan to unveil the sample of the near-Earth asteroid in a broadcast event on October 11.
Tomorrow's picture: shine on
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
39
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 September 28
The Deep Lagoon
Image Credit & Copyright: Josep Drudis, Christian Sasse
Explanation: Ridges of glowing interstellar gas and dark dust clouds inhabit the turbulent, cosmic depths of the Lagoon Nebula. Also known as M8, The bright star forming region is about 5,000 light-years distant. It makes for a popular stop on telescopic tours of the constellation Sagittarius toward the center of our Milky Way Galaxy. Dominated by the telltale red emission of ionized hydrogen atoms recombining with stripped electrons, this deep telescopic view of the Lagoon's central reaches is about 40 light-years across. The bright hourglass shape near the center of the frame is gas ionized and sculpted by energetic radiation and extreme stellar winds from a massive young star.
Tomorrow's picture:just back from Bennu
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
40
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 September 28
The Deep Lagoon
Image Credit & Copyright: Josep Drudis, Christian Sasse
Explanation: Ridges of glowing interstellar gas and dark dust clouds inhabit the turbulent, cosmic depths of the Lagoon Nebula. Also known as M8, The bright star forming region is about 5,000 light-years distant. It makes for a popular stop on telescopic tours of the constellation Sagittarius toward the center of our Milky Way Galaxy. Dominated by the telltale red emission of ionized hydrogen atoms recombining with stripped electrons, this deep telescopic view of the Lagoon's central reaches is about 40 light-years across. The bright hourglass shape near the center of the frame is gas ionized and sculpted by energetic radiation and extreme stellar winds from a massive young star.
Tomorrow's picture:just back from Bennu
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
41
Astronomy Picture of the Day
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 September 25
Arp 142: The Hummingbird Galaxy
Image Credit: NASA, ESA, Hubble, HLA; Processing & Copyright: Basudeb Chakrabarti
Explanation: What's happening to this spiral galaxy? Just a few hundred million years ago, NGC 2936, the upper of the two large galaxies shown at the bottom, was likely a normal spiral galaxy -- spinning, creating stars -- and minding its own business. But then it got too close to the massive elliptical galaxy NGC 2937, just below, and took a turn. Sometimes dubbed the [Hummingbird](https://en.wikipedia.org/wiki/Hummingbird#/media/File:Ruby- Throated_Hummingbird.png) Galaxy for its iconic shape, NGC 2936 is not only being deflected but also being distorted by the close gravitational interaction. Behind filaments of dark interstellar dust, bright blue stars form the nose of the hummingbird, while the center of the spiral appears as an eye. Alternatively, the galaxy pair, together known as Arp 142, look to some like Porpoise or a penguin protecting an egg. The featured re-processed image showing Arp 142 in great detail was taken recently by the Hubble Space Telescope. Arp 142 lies about 300 million light years away toward the constellation of the Water Snake (Hydra). In a billion years or so the two galaxies will likely merge into one larger galaxy.
Tomorrow's picture:big blue horse
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
42
Astronomy Picture of the Day
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 September 25
Arp 142: The Hummingbird Galaxy
Image Credit: NASA, ESA, Hubble, HLA; Processing & Copyright: Basudeb Chakrabarti
Explanation: What's happening to this spiral galaxy? Just a few hundred million years ago, NGC 2936, the upper of the two large galaxies shown at the bottom, was likely a normal spiral galaxy -- spinning, creating stars -- and minding its own business. But then it got too close to the massive elliptical galaxy NGC 2937, just below, and took a turn. Sometimes dubbed the [Hummingbird](https://en.wikipedia.org/wiki/Hummingbird#/media/File:Ruby- Throated_Hummingbird.png) Galaxy for its iconic shape, NGC 2936 is not only being deflected but also being distorted by the close gravitational interaction. Behind filaments of dark interstellar dust, bright blue stars form the nose of the hummingbird, while the center of the spiral appears as an eye. Alternatively, the galaxy pair, together known as Arp 142, look to some like Porpoise or a penguin protecting an egg. The featured re-processed image showing Arp 142 in great detail was taken recently by the Hubble Space Telescope. Arp 142 lies about 300 million light years away toward the constellation of the Water Snake (Hydra). In a billion years or so the two galaxies will likely merge into one larger galaxy.
Tomorrow's picture:big blue horse
< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >
**Authors & editors: ** Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.
43
Methane Discovered on Distant Exoplanet
Illustration Credit: Ahmad Jabakenji (ASU Lebanon, North Star Space Art); Data: NASA, ESA, CSA, JWST
Explanation: Where else might life exist? One of humanity's great outstanding questions, locating planets where extrasolar life might survive took a step forward in 2019 with the discovery of a significant amount of water vapor in the atmosphere of distant exoplanet K2-18b. The planet and its parent star, K2-18, lie about 124 light years away toward the constellation of the Lion (Leo). The exoplanet is significantly larger and more massive than our Earth, but orbits in the habitable zone of its home star. K2-18, although more red than our Sun, shines in K2-18b's sky with a brightness similar to the Sun in Earth's sky. The 2019 discovery of atmospheric water was made in data from three space telescopes: Hubble, Spitzer, and Kepler, by noting the absorption of water-vapor colors when the planet moved in front of the star. Now in 2023, further observations by the Webb Space Telescope in infrared light have uncovered evidence of other life-indicating molecules -- including methane. The featured illustration imagines exoplanet K2-18b on the far right orbited by a moon (center), which together orbit a red dwarf star depicted on the lower left.
44
Methane Discovered on Distant Exoplanet
Illustration Credit: Ahmad Jabakenji (ASU Lebanon, North Star Space Art); Data: NASA, ESA, CSA, JWST
Explanation: Where else might life exist? One of humanity's great outstanding questions, locating planets where extrasolar life might survive took a step forward in 2019 with the discovery of a significant amount of water vapor in the atmosphere of distant exoplanet K2-18b. The planet and its parent star, K2-18, lie about 124 light years away toward the constellation of the Lion (Leo). The exoplanet is significantly larger and more massive than our Earth, but orbits in the habitable zone of its home star. K2-18, although more red than our Sun, shines in K2-18b's sky with a brightness similar to the Sun in Earth's sky. The 2019 discovery of atmospheric water was made in data from three space telescopes: Hubble, Spitzer, and Kepler, by noting the absorption of water-vapor colors when the planet moved in front of the star. Now in 2023, further observations by the Webb Space Telescope in infrared light have uncovered evidence of other life-indicating molecules -- including methane. The featured illustration imagines exoplanet K2-18b on the far right orbited by a moon (center), which together orbit a red dwarf star depicted on the lower left.
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Explanation: Do stars always create jets as they form? No one is sure. As a gas cloud gravitationally contracts, it forms a disk that can spin too fast to continue contracting into a protostar. Theorists hypothesize that this spin can be reduced by expelling jets. This speculation coincides with known Herbig-Haro (HH) objects, young stellar objects seen to emit jets -- sometimes in spectacular fashion. Pictured is Herbig-Haro 211, a young star in formation recently imaged by the Webb Space Telescope (JWST) in infrared light and in great detail. Along with the two narrow beams of particles, red shock waves can be seen as the outflows impact existing interstellar gas. The jets of HH 221 will likely change shape as they brighten and fade over the next 100,000 years, as research into the details of star formation continues.
46
Explanation: Do stars always create jets as they form? No one is sure. As a gas cloud gravitationally contracts, it forms a disk that can spin too fast to continue contracting into a protostar. Theorists hypothesize that this spin can be reduced by expelling jets. This speculation coincides with known Herbig-Haro (HH) objects, young stellar objects seen to emit jets -- sometimes in spectacular fashion. Pictured is Herbig-Haro 211, a young star in formation recently imaged by the Webb Space Telescope (JWST) in infrared light and in great detail. Along with the two narrow beams of particles, red shock waves can be seen as the outflows impact existing interstellar gas. The jets of HH 221 will likely change shape as they brighten and fade over the next 100,000 years, as research into the details of star formation continues.
