Being so close to the sun is very hard on comets for many reasons. They are subjected to a lot of solar radiation which boils off their water or other volatiles. The physical push of the radiation and the solar wind also helps form the tails. And as they get closer to the sun, the comets experience extremely strong tidal forces, or gravitational stress. In this hostile environment, many sungrazers do not survive their trip around the sun. Although they don't actually crash into the solar surface, the sun is able to destroy them anyway.
Many sungrazing comets follow a similar orbit, called the Kreutz Path, and collectively belong to a population called the Kreutz Group. In fact, close to 85% of the sungrazers seen by the SOHO satellite are on this orbital highway. Scientists think one extremely large sungrazing comet broke up hundreds, or even thousands, of years ago, and the current comets on the Kreutz Path are the leftover fragments of it. As clumps of remnants make their way back around the sun, we experience a sharp increase in sungrazing comets, which appears to be going on now. Comet Lovejoy, which reached perihelion on December 15, 2011 is the best known recent Kreutz-group sungrazer. And so far, it is the only one that NASA's solar-observing fleet has seen survive its trip around the sun.
Comet ISON, an upcoming sungrazer with a perihelion of 730,000 miles on November 28, 2013, is not on the Kreutz Path. In fact, ISON's orbit suggests that it may gain enough momentum to escape the solar system entirely, and never return. Before it does so, it will pass within about 40 million miles from Earth on December 26th. Assuming it survives its trip around the sun.", "items": [], "extra_data": {} }, { "id": 345358, "url": "https://svs.gsfc.nasa.gov/11307/#media_group_345358", "widget": "Video player", "title": "", "caption": "", "description": "Short, narrated video about sungrazing comets.
Watch this video on the NASAexplorer YouTube channel.
For complete transcript, click here.", "items": [ { "id": 307228, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 463840, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/Sungrazer_Still.png", "filename": "Sungrazer_Still.png", "media_type": "Image", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "width": 1280, "height": 720, "pixels": 921600 } }, { "id": 307229, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 463845, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/Sungrazer_Still_web.jpg", "filename": "Sungrazer_Still_web.jpg", "media_type": "Image", "alt_text": "Sungrazing comets are a special class of comets that come very close to the sun at their nearest approach, a point called perihelion. To be considered a sungrazer, a comet needs to get within about 850,000 miles from the sun at perihelion. Many come even closer, even to within a few thousand miles. Being so close to the sun is very hard on comets for many reasons. They are subjected to a lot of solar radiation which boils off their water or other volatiles. The physical push of the radiation and the solar wind also helps form the tails. And as they get closer to the sun, the comets experience extremely strong tidal forces, or gravitational stress. In this hostile environment, many sungrazers do not survive their trip around the sun. Although they don't actually crash into the solar surface, the sun is able to destroy them anyway. Many sungrazing comets follow a similar orbit, called the Kreutz Path, and collectively belong to a population called the Kreutz Group. In fact, close to 85% of the sungrazers seen by the SOHO satellite are on this orbital highway. Scientists think one extremely large sungrazing comet broke up hundreds, or even thousands, of years ago, and the current comets on the Kreutz Path are the leftover fragments of it. As clumps of remnants make their way back around the sun, we experience a sharp increase in sungrazing comets, which appears to be going on now. Comet Lovejoy, which reached perihelion on December 15, 2011 is the best known recent Kreutz-group sungrazer. And so far, it is the only one that NASA's solar-observing fleet has seen survive its trip around the sun. Comet ISON, an upcoming sungrazer with a perihelion of 730,000 miles on November 28, 2013, is not on the Kreutz Path. In fact, ISON's orbit suggests that it may gain enough momentum to escape the solar system entirely, and never return. Before it does so, it will pass within about 40 million miles from Earth on December 26th. Assuming it survives its trip around the sun.", "width": 180, "height": 320, "pixels": 57600 } }, { "id": 307230, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 463846, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/Sungrazer_Still_thm.png", "filename": "Sungrazer_Still_thm.png", "media_type": "Image", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "width": 80, "height": 40, "pixels": 3200 } }, { "id": 307219, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 463841, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/11307_Sungrazer_ProRes_1280x720_59.94.mov", "filename": "11307_Sungrazer_ProRes_1280x720_59.94.mov", "media_type": "Movie", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click 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video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "width": 960, "height": 540, "pixels": 518400 } }, { "id": 307226, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 463851, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/G2013-050_Sungrazing_Comets_FINAL_ipod_lg.m4v", "filename": "G2013-050_Sungrazing_Comets_FINAL_ipod_lg.m4v", "media_type": "Movie", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "width": 640, "height": 360, "pixels": 230400 } }, { "id": 307232, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 853631, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/11307_Sungrazer_SRT_Captions.en_US.srt", "filename": "11307_Sungrazer_SRT_Captions.en_US.srt", "media_type": "Captions", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "label": "English", "language_code": "" } }, { "id": 307233, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 853632, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/11307_Sungrazer_SRT_Captions.en_US.vtt", "filename": "11307_Sungrazer_SRT_Captions.en_US.vtt", "media_type": "Captions", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "label": "English", "language_code": "" } }, { "id": 307227, "type": "media", "extra_data": null, "title": null, "caption": null, "instance": { "id": 463848, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011307/G2013-050_Sungrazing_Comets_FINAL_ipod_sm.mp4", "filename": "G2013-050_Sungrazing_Comets_FINAL_ipod_sm.mp4", "media_type": "Movie", "alt_text": "Short, narrated video about sungrazing comets.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here.", "width": 320, "height": 240, "pixels": 76800 } } ], "extra_data": {} }, { "id": 345359, "url": "https://svs.gsfc.nasa.gov/11307/#media_group_345359", "widget": "Basic text", "title": "For More Information", "caption": "", "description": "See [http://www.nasa.gov/content/goddard/timeline-of-comet-ison-s-dangerous-journey/](http://www.nasa.gov/content/goddard/timeline-of-comet-ison-s-dangerous-journey/)", "items": [], "extra_data": {} } ], "studio": "gms", "funding_sources": [ "NASA Heliophysics" ], "credits": [ { "role": "Video editor", "people": [ { "name": "Scott Wiessinger", "employer": "USRA" } ] }, { "role": "Producer", "people": [ { "name": "Scott Wiessinger", "employer": "USRA" } ] }, { "role": "Writer", "people": [ { "name": "Karen Fox", "employer": "ADNET Systems, Inc." }, { "name": "Scott Wiessinger", "employer": "USRA" } ] } ], "missions": [ "SDO", "SOHO", "STEREO" ], "series": [ "Narrated Movies" ], "tapes": [ "Sungrazing Comet Primer (Produced by: Robert Crippen)" ], "papers": [], "datasets": [], "nasa_science_categories": [ "Planets & Moons", "Sun" ], "keywords": [ "Comet", "Comet Encke", "Corona", "Coronal Mass Ejections", "Earth Science", "HDTV", "Heliophysics", "SDO", "SOHO", "Solar Activity", "Solar Dynamics Observatory", "Solar Ultraviolet", "Solar Wind", "STEREO", "Sun-earth Interactions", "Sungrazing Comets" ], "recommended_pages": [], "related": [ { "id": 14552, "url": "https://svs.gsfc.nasa.gov/14552/", "page_type": "Produced Video", "title": "Volunteers Help ESA & NASA Mission to Discover 5,000 Comets", "description": "The Solar and Heliospheric Observatory (SOHO), a joint mission of ESA (European Space Agency) and NASA, has discovered its 5,000th comet, thanks to the help of volunteer comet hunters participating in the NASA-funded Sungrazer Project.The sungrazing comet was spotted in SOHO images on March 25, 2024, by Hanjie Tan in the Czech Republic, who has participated in the Sungrazer Project since he was 13 years old. The comet is small and has a short orbital period around the Sun. It belongs to the “Marsden group” of comets, which are thought to be related to the larger comet 96P/Machholz. The group is named after the late scientist Brian Marsden, who first recognized the group using SOHO observations.To learn more about the discovery and SOHO, visit: https://science.nasa.gov/science-research/heliophysics/esa-nasa-solar-observatory-discovers-its-5000th-comet/Since the early 2000s, the Sungrazer Project has allowed anyone with a computer to search for comets in images taken by the SOHO spacecraft.To learn more about the Sungrazer Project, visit: https://science.nasa.gov/citizen-science/the-sungrazer-project/ || ", "release_date": "2024-03-27T10:00:00-04:00", "update_date": "2024-03-26T15:33:26.792521-04:00", "main_image": { "id": 1090387, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a014500/a014552/SOHO4995.00030_print.jpg", "filename": "SOHO4995.00030_print.jpg", "media_type": "Image", "alt_text": "This annotated movie from the European Space Agency & NASA’s SOHO observatory shows the 4,995th comet discovered by the spacecraft as it speeds toward the Sun on March 14, 2024.Credit: ESA/NASA/SOHO/Karl Battams", "width": 1024, "height": 757, "pixels": 775168 } }, { "id": 13622, "url": "https://svs.gsfc.nasa.gov/13622/", "page_type": "Produced Video", "title": "Counting Comets", "description": "Music Credit: Birds in The Rain by Robert GuerrierComplete transcript available.Watch this video on the NASA Goddard YouTube channel. || cometthumb.jpg (1920x1080) [404.7 KB] || cometthumb_print.jpg (1024x576) [192.3 KB] || cometthumb_searchweb.png (320x180) [56.6 KB] || cometthumb_web.png (320x180) [56.6 KB] || cometthumb_thm.png (80x40) [5.1 KB] || 13622.Counting_Comets.Mobile720.mp4 (1280x720) [108.5 MB] || 13622.Counting_Comets.Twitter1080.mp4 (1920x1080) [40.1 MB] || 13622.Counting_CometsFB.mp4 (1920x1080) [215.9 MB] || 13622.Counting_Comets.YouTube1080.mp4 (1920x1080) [284.3 MB] || 13622.Counting_Comets.YouTube1080.webm (1920x1080) [20.2 MB] || Counting_CometsAPR.mov (1920x1080) [4.4 GB] || 13622Comets.en_US.srt [3.6 KB] || 13622Comets.en_US.vtt [3.7 KB] || ", "release_date": "2020-05-19T10:00:00-04:00", "update_date": "2023-05-03T13:44:57.683699-04:00", "main_image": { "id": 385035, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a013600/a013622/cometthumb.jpg", "filename": "cometthumb.jpg", "media_type": "Image", "alt_text": "Music Credit: Birds in The Rain by Robert GuerrierComplete transcript available.Watch this video on the NASA Goddard YouTube channel.", "width": 1920, "height": 1080, "pixels": 2073600 } }, { "id": 11422, "url": "https://svs.gsfc.nasa.gov/11422/", "page_type": "Produced Video", "title": "NASA's Solar Observing Fleet Watch Comet ISON's Journey Around the Sun", "description": "After several days of continued observations, scientists continue to work to determine and to understand the fate of Comet ISON: There's no doubt that the comet shrank in size considerably as it rounded the sun and there's no doubt that something made it out on the other side to shoot back into space. The question remains as to whether the bright spot seen moving away from the sun was simply debris, or whether a small nucleus of the original ball of ice was still there. Regardless, it is likely that it is now only dust. The comet was visible in instruments on NASA's Solar Terrestrial Relations Observatory, or STEREO, and the joint European Space Agency/NASA Solar and Heliospheric Observatory, or SOHO, via images called coronagraphs.Watch this video on the NASA Goddard YouTube channel.Credit:NASA/STEREO/ESA/SOHO/SDOGSFC || STEREO_A_Cor2_Still.jpg (1280x720) [494.6 KB] || STEREO_A_Cor2_Still_web.png (320x180) [67.2 KB] || ISON_Full_FINAL_1280x720.wmv (1280x720) [49.4 MB] || ISON_Full_FINAL_appletv.m4v (960x540) [46.4 MB] || ISON_Full_H264_1280x720_30.mov (1280x720) [43.1 MB] || ISON_Full_MPEG4_1280X720_29.97.mp4 (1280x720) [28.0 MB] || ISON_Full_FINAL_appletv.webmhd.webm (960x540) [16.6 MB] || ISON_Full_FINAL_ipod_lg.m4v (640x360) [17.5 MB] || ISON_Full_FINAL.mp4 (320x240) [8.3 MB] || ISON_Full_FINAL_ipod_sm.mp4 (320x240) [8.3 MB] || ISON_Full_ProRes_1280x720_29.97.mov (1280x720) [810.6 MB] || ISON_Full_H264_Best_1280x720_29.97.mov (1280x720) [517.2 MB] || ISON_Full_H264_Good_1280x720_29.97.mov (1280x720) [124.1 MB] || ISON_Full_FINAL_youtube_hq.mov (1280x720) [124.1 MB] || ", "release_date": "2013-11-22T11:00:00-05:00", "update_date": "2023-05-03T13:51:25.912803-04:00", "main_image": { "id": 460681, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011400/a011422/ison_encke_hi1_srem_a_web.jpg", "filename": "ison_encke_hi1_srem_a_web.jpg", "media_type": "Image", "alt_text": "Comet C/2012 S1 (ISON) has entered the NASA STEREO/SECCHI HI-1A field of view where it joins the Earth, Mercury and comet 2P/Encke. Credit: Karl Battams/NASA/STEREO/CIOC", "width": 320, "height": 273, "pixels": 87360 } }, { "id": 11384, "url": "https://svs.gsfc.nasa.gov/11384/", "page_type": "Produced Video", "title": "How to Cook a Comet", "description": "A comet's journey through the solar syste is perilous and violent. Before it reaches Mars - at some 230 million miles away from the sun - the radiation of the sun begins to cook off the frozen water ice directly into gas. This is called sublimation. It is the first step toward breaking the comet apart. If it survives this, the intense radiation and pressure closer to the sun could destroy it altogether.Animators at NASA's Goddard Space Flight Center in Greenbelt, Md. created this short movie showing how the sun can cook a comet. Such a journey is currently being made by Comet ISON. It began its trip from the Oort cloud region of our solar system and is now traveling toward the sun. The comet will reach its closest approach to the sun on Thanksgiving Day — Nov. 28, 2013 — skimming just 730,000 miles above the sun’s surface. If it comes around the sun without breaking up, the comet will be visible in the Northern Hemisphere with the naked eye, and from what we see now, ISON is predicted to be a particularly bright and beautiful comet. Even if the comet does not survive, tracking its journey will help scientists understand what the comet is made of, how it reacts to its environment, and what this explains about the origins of the solar system. Closer to the sun, watching how the comet and its tail interact with the vast solar atmosphere can teach scientists more about the sun itself. || ", "release_date": "2013-11-21T14:00:00-05:00", "update_date": "2023-05-03T13:51:26.102592-04:00", "main_image": { "id": 461733, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011300/a011384/cometcooking320.jpg", "filename": "cometcooking320.jpg", "media_type": "Image", "alt_text": "Watch this video on the Goddard YouTube channel.", "width": 320, "height": 180, "pixels": 57600 } }, { "id": 11222, "url": "https://svs.gsfc.nasa.gov/11222/", "page_type": "Produced Video", "title": "The Path of Comet ISON", "description": "Comet C/2012 S1, better known as comet ISON, may become a dazzling sight as it traverses the inner solar system in late 2013. During the weeks before its Nov. 28 close approach to the sun, the comet will be observable with small telescopes, and binoculars. Observatories around the world and in space will track the comet during its fiery trek around the sun. If ISON survives its searing solar passage, which seems likely but is not certain, the comet may be visible to the unaided eye in the pre-dawn sky during December.Watch the animations on this page to visualize ISON's voyage through the inner solar system, or build the paper model of its orbit to track the changing positions of Earth and the comet.Like all comets, ISON is a clump of frozen gases mixed with dust. Often described as \"dirty snowballs,\" comets emit gas and dust whenever they venture near enough to the sun that the icy material transforms from a solid to gas, a process called sublimation. Jets powered by sublimating ice also release dust, which reflects sunlight and brightens the comet. On Nov. 28, ISON will make a sweltering passage around the sun. The comet will approach within about 730,000 miles (1.2 million km) of its visible surface, which classifies ISON as a sungrazing comet. In late November, its icy material will furiously sublimate and release torrents of dust as the surface erodes under the sun's fierce heat, all as sun-monitoring satellites look on. Around this time, the comet may become bright enough to glimpse just by holding up a hand to block the sun's glare.Sungrazing comets often shed large fragments or even completely disrupt following close encounters with the sun, but for ISON neither fate is a forgone conclusion.Following ISON's solar swingby, the comet will depart the sun and move toward Earth, appearing in morning twilight through December. The comet will swing past Earth on Dec. 26, approaching within 39.9 million miles (64.2 million km) or about 167 times farther than the moon.The comet was discovered on Sept 21, 2012, by Russian astronomers Vitali Nevski and Artyom Novichonok using a telescope of the International Scientific Optical Network (ISON) located near Kislovodsk.Learn more about sungrazing comets. || ", "release_date": "2013-03-29T11:00:00-04:00", "update_date": "2025-01-05T00:17:07.797970-05:00", "main_image": { "id": 467495, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011200/a011222/Instruction_still.png", "filename": "Instruction_still.png", "media_type": "Image", "alt_text": "This paper model illustrates the comet's path during its six-month trek in the vicinity of Earth, Venus and Mercury. Track how the relationship between Earth and the comet constantly changes by referring to the dates along both orbits.Download the pdf with instructions here.", "width": 934, "height": 602, "pixels": 562268 } }, { "id": 11156, "url": "https://svs.gsfc.nasa.gov/11156/", "page_type": "Produced Video", "title": "Sungrazers Galore", "description": "Before 1979, there were less than a dozen known sungrazing comets. As of December 2012, we know of 2,500. Why did this number increase? With solar observatories like SOHO, STEREO, and SDO, we have not only better means of viewing the sun, but also the comets that approach it. SOHO allows us to see smaller, fainter comets closer to the sun than we have ever been able to see before. Even though many of these comets do not survive their journey past the sun, they survive long enough to be observed, and be added to our record of sungrazing comets. || ", "release_date": "2013-02-06T10:00:00-05:00", "update_date": "2023-05-03T13:52:25.477182-04:00", "main_image": { "id": 469957, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011100/a011156/Counting_Comets_Still.png", "filename": "Counting_Comets_Still.png", "media_type": "Image", "alt_text": "Why are we seeing so many sungrazing comets?", "width": 1264, "height": 709, "pixels": 896176 } }, { "id": 4018, "url": "https://svs.gsfc.nasa.gov/4018/", "page_type": "Visualization", "title": "Kreutz Comet Orbits", "description": "HD movie of representative orbit of a sungrazing comet. || Kreutz.noslate_HEEmove.HD1080i.0350.jpg (1920x1080) [582.0 KB] || Kreutz.noslate_HEEmove.HD1080i.0350_web.png (320x180) [92.0 KB] || Kreutz.noslate_HEEmove.HD1080i.0350_thm.png (80x40) [4.5 KB] || Kreutz-Lovejoy_HD1080.mov (1920x1080) [13.2 MB] || Kreutz-Lovejoy_HD1080.mp4 (1920x1080) [13.2 MB] || 1920x1080_16x9_30p (1920x1080) [64.0 KB] || Kreutz-Lovejoy_HD1080.webmhd.webm (960x540) [2.9 MB] || Kreutz-Lovejoy_iPod.m4v (640x360) [3.0 MB] || ", "release_date": "2012-12-10T00:00:00-05:00", "update_date": "2023-05-03T13:52:31.997296-04:00", "main_image": { "id": 470047, "url": "https://svs.gsfc.nasa.gov/vis/a000000/a004000/a004018/Kreutz.noslate_HEEmove.HD1080i.0350.jpg", "filename": "Kreutz.noslate_HEEmove.HD1080i.0350.jpg", "media_type": "Image", "alt_text": "HD movie of representative orbit of a sungrazing comet.", "width": 1920, "height": 1080, "pixels": 2073600 } }, { "id": 11158, "url": "https://svs.gsfc.nasa.gov/11158/", "page_type": "Produced Video", "title": "Sun Grazing Comets as Solar Probes", "description": "To observe how winds move high in Earth's atmosphere, scientists sometimes release clouds of barium as tracers to track how the material corkscrews and sweeps around — but scientists have no similar technique to study the turbulent atmosphere of the sun. So researchers were excited in December 2011, when Comet Lovejoy swept right through the sun's corona with its long tail streaming behind it. NASA's Solar Dynamics Observatory (SDO) captured images of the comet, showing how its long tail was buffeted by systems around the sun, offering scientists a unique way of observing movement as if they'd orchestrated the experiment themselves. Since comet tails have ionized gases, they are also affected by the sun's magnetic field, and can act as tracers of the complex magnetic system higher up in the atmosphere. Comets can also aid in the study of coronal mass ejections and the solar wind.Watch this video on YouTube. || ", "release_date": "2012-12-04T15:00:00-05:00", "update_date": "2023-05-03T13:52:33.497083-04:00", "main_image": { "id": 469988, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011100/a011158/LovejoyCloseup_stand.HD1080i.00600.jpg", "filename": "LovejoyCloseup_stand.HD1080i.00600.jpg", "media_type": "Image", "alt_text": "Short narrated video.For complete transcript, click here.", "width": 1920, "height": 1080, "pixels": 2073600 } }, { "id": 10886, "url": "https://svs.gsfc.nasa.gov/10886/", "page_type": "Produced Video", "title": "SDO Sees Comet Lovejoy Survive Close Encounter With Sun", "description": "One instrument watching for the comet was the Solar Dynamics Observatory (SDO), which adjusted its cameras in order to watch the trajectory. Not only does this help with comet research, but it also helps orient instruments on SDO—since the scientists know where the comet is based on other spacecraft, they can finely determine the position of SDO's mirrors. This first clip from SDO from the evening of Dec 15, 2011 shows Comet Lovejoy moving in toward the sun. Comet Lovejoy survived its encounter with the sun. The second clip shows the comet exiting from behind the right side of the sun, after an hour of travel through its closest approach to the sun. By tracking how the comet interacts with the sun's atmosphere, the corona, and how material from the tail moves along the sun's magnetic field lines, solar scientists hope to learn more about the corona. This movie was filmed by the Solar Dynamics Observatory in 171 angstrom wavelength, which is typically shown in yellow.Credit: NASA/SDO || ", "release_date": "2011-12-19T22:00:00-05:00", "update_date": "2023-05-03T13:53:22.302326-04:00", "main_image": { "id": 480444, "url": "https://svs.gsfc.nasa.gov/vis/a010000/a010800/a010886/Comet_Lovejoy_Still_2.jpg", "filename": "Comet_Lovejoy_Still_2.jpg", "media_type": "Image", "alt_text": "Slowed and looped video with music.For complete transcript, click here.", "width": 1280, "height": 720, "pixels": 921600 } } ], "sources": [], "products": [], "newer_versions": [], "older_versions": [], "alternate_versions": [] }