Skip all navigation and jump to content Jump to site navigation Jump to section navigation.
NASA Logo - Goddard Space Flight Center + Visit

+ Advanced Search
View Most Recently Released Imagery
View Gallery of Imagery: A topical collection of SVS Imagery
Search Imagery by the keywords assigned to it
Search Imagery by the instruments that supplied data for a visualization product
Search Imagery by the series of visualizations that have been produced
Search Imagery by the scientist providing the data used in a visualization product
Search Imagery by the animator that created the product
Search Imagery by the identification number assigned to the visualization product
See other search options

  + RSS Feeds
  + Podcasts
blank image
Previous Animation Number   Next Animation Number
What is a Sungrazing Comet?

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.

Share: Share via E-mail E-mail   Share on TwitterTwitter
Other multimedia items related to this story:
     The Path of Comet ISON (id 11222)
     Kreutz Comet Orbits (id 4018)
     Sun Grazing Comets as Solar Probes (id 11158)
     SDO Sees Comet Lovejoy Survive Close Encounter With Sun (id 10886)
     Sungrazers Galore (id 11156)
More information on this topic available at:

Short, narrated video about sungrazing comets. Watch this video on the NASAexplorer YouTube channel.    Short, narrated video about sungrazing comets.

Watch this video on the NASAexplorer YouTube channel.

For complete transcript, click here.
Duration: 3.1 minutes
Available formats:
  1280x720 (59.94 fps) QT         3 GB
  1280x720 (59.94 fps) QT         1 GB
  1280x720 (29.97 fps) QT         245 MB
  1280x720 (29.97 fps) QT         112 MB
  1280x720 (29.97 fps) WMV         98 MB
  1280x720 (29.97 fps) MPEG-4   81 MB
  960x540 (29.97 fps) MPEG-4   89 MB
  640x360 (29.97 fps) MPEG-4   35 MB
  320x240 (29.97 fps) MPEG-4   18 MB
  1280x720   PNG           782 KB
  960x540 (29.97 fps) WEBM         38 MB
  320x180     JPEG         12 KB
How to play our movies

Short URL to This Page:
Animation Number:11307
Video Editor:Scott Wiessinger (USRA)
Producer:Scott Wiessinger (USRA)
Writers:Karen Fox (ASI)
 Scott Wiessinger (USRA)
Series:Narrated Movies
Goddard TV Tape:G2013-050 -- Sungrazing Comet Primer
Please give credit for this item to:
NASA's Goddard Space Flight Center
SVS >> Comet
SVS >> Coronal Mass Ejection
SVS >> Solar Ultraviolet
SVS >> Solar Wind
SVS >> Sun
SVS >> Comet Encke
SVS >> Solar Dynamics Observatory
SVS >> Heliophysics
SVS >> Corona
NASA Science >> Sun
NASA Science >> Planets and Moons
SVS >> Sungrazer
SVS >> Sungrazing Comets

Back to Top
Many of our multimedia items use the GCMD keywords. These keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version logo - the U.S. Government's official Web portal. + Privacy Policy and Important Notices
+ Reproduction Guidelines
NASA NASA Official:
Content Contact: