SOHO/LASCO COMET OBSERVATIONS
For a larger image,
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The composite image above was created using three different instruments on
the Solar and Heliospheric Observatory (SOHO). The solar disk image was
taken by the Extreme Ultraviolet Imaging Telescope (EIT) in the Fe XV
line at 284 Angstroms. This has an approximate temperature of 2-2.5
million Kelvin. The sun's lower corona was imaged in the O VI line by
the Ultraviolet Coronagraph Spectrometer (UVCS). The outermost image
of the corona, shown in white light, was taken by SOHO's Large Angle
Spectrometric Coronagraph (LASCO)
on December 23, 1996 with the C3 coronagraph. Visible in the corona are
several prominent streamers, one on the left (East) side of the sun and
two on the right (West). The image shows comet SOHO-6 (C/1996 Y1) located
at the bottom left of the sun. Also visible is the Milky Way, which stretches
from the top to the bottom in the image.
SOHO is a cooperative mission between the European Space Agency (ESA)
and the National Aeronautics and Space Administration (NASA). SOHO
studies the sun from deep down in its core out to 32 solar radii. The
spacecraft orbits the L1 Lagrangian point. From this orbit, SOHO is
able to observe the sun 24 hours a day. It carries twelve state-of-the-art
instruments expected to meet the mission's three principal
scientific objectives. These objectives are: to study the solar
interior, to study the heating mechanisms of the solar corona, and to
investigate the solar wind and its acceleration processes.
Even though SOHO's primary objectives relate to solar and heliospheric physics, the onboard
LASCO instrument has become the most prolific comet discoverer in history!
LASCO is a three-coronagraph package (C1, C2, & C3) with nested field of views of 1.1-3,
2.5-6, and 4-32 solar radii, respectively. The C1 instrument was designed to observe
hot coronal emission and, therefore, has not observed any comets. However, since LASCO began taking
observations in January of 1996, the C2 and C3 coronagraphs have observed over
new comets and several known comets. In addition, the SWAN instrument onboard SOHO
has discovered 4 new comets and observed many known objects. The UVCS instrument
has also observed a handful of known comets.
|SWAN image of comets Kudo-Fujikawa, NEAT, & Juels-Holvorcem (path not shown).
||LASCO C3 image of comet NEAT (C/2002 V1).
||UVCS image of SOHO6 (C/1996 Y1).
|Mpeg (2.2 MB)
||Mpeg (1.9 MB)
Want to discover a SOHO comet?
All the information and links you need are here!