Sixteen Comets Touring the Inner Solar System

This visualization presents 14 years of comets seen by SOHO from the perspective of an observer orbiting a fixed point above the ecliptic plane with the Sun at the center.This video is also available on our YouTube channel. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer at the Sun-Earth Lagrange Point 1, approximately the position of SOHO. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer above the ecliptic plane looking 'down' on the solar system with the Sun at the center. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer at a fixed point above the ecliptic plane with the Sun at the center. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer at a fixed point in the ecliptic plane with the Sun at the center. Stationed in a halo orbit around the Earth-Sun Lagrange point since 1996, the Solar and Heliospheric Observatory (SOHO) has monitored the Sun for nearly 20 years. The Large Angle and Spectrometric Coronagraph (LASCO) instrument blocks out the bright solar disk, making it easier to see the corona of plasma and dust around the Sun, normally only visible during solar eclipses. This instrument also provides a very large field of view of the region around the Sun.In addition to the benefit of this capability in solar studies, SOHO/LASCO can see many comets which pass very close to the Sun, called 'sungrazers'. Observers on Earth rarely see these objects as they are obstructed by the Sun's glare and Earth's atmospheric scattering at sunrise and sunset. SOHO/LASCO has seen not only many known comets, but discovered many more NEW sungrazing comets. At the time of this writing, the discovery count is approaching 3000.There are nearly 1800 comets and trajectories plotted in these visualizations which covers the time frame from January 1996 to May 2010 at the rate of one frame of the movie corresponding to one day. The great majority of these comets are Kreutz group members (the red trails). The trails are color coded based on group membership.Yellow - unaffiliated cometsRed - Kreutz group. Green - Meyer groupBlue - MarsdenCyan - KrachtMagenta - Kracht 2Important Notes and Caveats:This version of the visualization provides long trails for the periodic comets so the entire orbit is visible and they can be distinguished from the one-time visitors to the inner solar system. An alternate version with short trails for all comets is available at Lot of Comets - Short trail versionThe Kreutz group comets rarely make it past perihelion (the closest pass to the Sun) so these orbits terminate a day after perihelion.The Kreutz group comets appear to stream sunward in bunches. This is an artifact of the fact that it is less likely for SOHO to detect incoming Kreutz objects during some parts of the year.The trails represent the orbital path of the comet nucleus, NOT the comet tail.Naval Research Laboratory (NRL) Sungrazing Comets Page Related pages

This visualization presents 14 years of comets seen by SOHO from the perspective of an observer at a fixed point above the ecliptic plane with the Sun at the center. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer at the Sun-Earth Lagrange Point 1, approximately the position of SOHO. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer orbiting a fixed point above the ecliptic plane with the Sun at the center. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer above the ecliptic plane looking 'down' on the solar system with the Sun at the center. This visualization presents 14 years of comets seen by SOHO from the perspective of an observer at a fixed point in the ecliptic plane with the Sun at the center. Stationed in a halo orbit around the Earth-Sun Lagrange point since 1996, the Solar and Heliospheric Observatory (SOHO) has monitored the Sun for nearly 20 years. The Large Angle and Spectrometric Coronagraph (LASCO) instrument blocks out the bright solar disk, making it easier to see the corona of plasma and dust around the Sun, normally only visible during solar eclipses. This instrument also provides a very large field of view of the region around the Sun.In addition to the benefit of this capability in solar studies, SOHO/LASCO can see many comets which pass very close to the Sun, called 'sungrazers'. Observers on Earth rarely see these objects as they are obstructed by the Sun's glare and Earth's atmospheric scattering at sunrise and sunset. SOHO/LASCO has seen not only many known comets, but discovered many more NEW sungrazing comets. At the time of this writing, the discovery count is approaching 3000.There are nearly 1800 comets and trajectories plotted in these visualizations which covers the time frame from January 1996 to May 2010 at the rate of one frame of the movie corresponding to one day. The great majority of these comets are Kreutz group members (the red trails). The trails are color coded based on group membership.Yellow - unaffiliated cometsRed - Kreutz group. Green - Meyer groupBlue - MarsdenCyan - KrachtMagenta - Kracht 2Important Notes and Caveats:This version of the visualization provides short trails for all comets. An alternate version with long trails for periodic comets is available at Lot of Comets - Long trail versionThe Kreutz group comets rarely make it past perihelion (the closest pass to the Sun) so these orbits terminate a day after perihelion.The Kreutz group comets appear to stream sunward in bunches. This is an artifact of the fact that it is less likely for SOHO to detect incoming Kreutz objects during some parts of the year.The trails represent the orbital path of the comet nucleus, NOT the comet tail.Naval Research Laboratory (NRL) Sungrazing Comets Page Related pages

Karl Battams of the Naval Research Lab talks us through a visualization of the comets that SOHO has witnessed.Watch this video on the NASAexplorer YouTube channel. Inset image of SOHO's 3,000th comet. Credit: SOHO/ESA/NASA/NRL Inset image of SOHO's 3,000th comet. Credit: SOHO/ESA/NASA/NRL Since its launch nearly 20 years ago, NASA and the European Space Agency's Solar and Heliospheric Observatory has spotted 3000 comets. The mission's The Large Angle and Spectrometric Coronagraph (LASCO) instrument blocks out the bright solar disk, making it easier to see the corona of plasma and dust around the Sun, normally only visible during solar eclipses. This instrument also provides a very large field of view of the region around the Sun.This visualization utilizes SOHO data from 1998 - 2010 and shows over 2000 comets. Comets that were first observed by SOHO carry no labels, and comets witnessed by not discovered by the spacecraft are represented with their labels. Trails on the comets are color coded based on family: yellow - unaffiliated comets, red - Kreutz group, green - Meyer group, blue - Marsden, cyan - Kracht, and magenta - Kracht 2. The visualizations without narration or music are also available. Related pages