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Subj:
rogues
page
Date: 6/1/00 5:24:02 AM Pacific Daylight Time
From: gurman@gsfc.nasa.gov (Joseph
B. Gurman)
To: bardsquill@aol.com |
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Hi -
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You certainly have an interesting collection
of non-solar,
non-cosmic ray features observed by the SOHO LASCO coronagraphs on
your:
rogues.html
page.
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I believe
the LASCO team all agree that
they are
foreground features (i.e., not solar in origin), though I don't recall hearing
much serious speculation on their origin. The length of the various
tracks is a reflection of the objects' apparent motion during the LASCO exposure
times (typically 12 - 25 seconds). Some of those that appear clearly to be
out of focus have been estimated to be only a few meters in front of the
SOHO spacecraft, and are therefore probably debris from the spacecraft
itself.
The sharper-appearing features could, however, be much farther
away. |
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I would object to the inclusion of the EIT
image you title
"strgte5sm.jpg"
with the LASCO images, however, since the long, nearly horizontal feature
in it is definitely of solar origin. Whenever we take time series of images
in our 304 Angstrom bandpass, we observe these "bifurcated jets" (i.e., jets
brighter along their edges than in the middle). There may be some streaking
due to the even longer (generally ~ 32 s) exposure time for EIT 304 Å
images, but their appearance on succeeding frames, and their origin in solar
active regions makes it clear that they are solar in origin. |
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Best,
Joe Gurman
US project scientist for SOHO
Co-Investigator, SOHO-EIT |
Some Images
sent by
IZAKOVIC
. . . ANGEL
SWORDS ..
6/1/00 11:18 C3 |