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Re: NEW COMET COMING OUR WAY THIS YEAR C/1999 H-1 (Lee)
Official Response From Joseph B. Gurman,
NASA/SOHO Project Scientist,
Unreported CME...06/12/99
"Joseph B. Gurman" wrote:
Sometimes I wish NASA could be clever enough to stage a coverup, but as far
as I can tell, we're not capable of such an effort: after all, when one starts to lie, one has
to remember what lie who told whom, and when. Beyond us.
Here is my understanding of this "event" and how it got to be a BBC news
story. At the Centennial meeting of the American Astronomical Society (AAS) in Chicago last
week --- a meeting very well attended by solar physicists, since the Society was
founded by George Ellery Hale, the pioneer solar physicist --- we (actually, ESA paid for
most of it) had a Solar and Heliospheric Observatory (SOHO) booth in the exhibition area. In
addition to "canned" videos of past SOHO observations and science presentations, the booth
included two PC's connected to the Internet; the PC's were provided by the group
at the Naval Research Laboratory who operate the LASCO coronagraphs on
SOHO. LASCO and the Extreme ultraviolet Imaging Telescope (EIT) share electronics, so the NRL
people as well as we (the EIT team) both reformat the EIT data and make movies of them.
The PC's from NRL were designed to grab movies of the most recent 24 hours
or so of images from LASCO C2, LASCO C3, and EIT from machines at the SOHO Experimenters'
Operations Facility (EOF) here at NASA Goddard Space Flight Center in Greenbelt Maryland, via
the Internet, and display them for the folks attending the AAS meeting exhibitions.
There were two problems with this:
1. The EIT CCD detector was being baked out over the Memorial Day weekend to improve its
performance (see: http://umbra.nascom.nasa.gov/eit/CCD_bakeout.html for more on CCD detectors
and why the EIT one needs to be baked out occasionally)
2. The reformatting software --- that turns the raw telemetry into viewable images --- on the
LASCO workstations in the EOF had broken down over the holiday weekend, when noone came in to
check on it. (Most of the people who usually did so were in Chicago, and the one other fellow
was on his boat on Chesapeake Bay.)
So, we didn't have very current movies of LASCO images for the first day and a half of the
meeting (May 32 - June 1), and then when the data started flowing again, we saw the great,
bright halo coronal mass ejection (CME). Unfortunately, what one needs to determine whether
the "halo" CME is headed towards or away from the earth --- they look the same in
white-light coronagraph images because the scattering geometry is identical --- is by looking
at what happens (or doesn't happen) in the lower corona: i.e., in EIT images.... and we
weren't getting any EIT images (aside from "darks" taken with the shutter closed, or
calibration images taken with a visible-light lamp flooding the CCD, to calibrate it after the
bakeout. This is a standard procedure every time we do a bakeout.
So the situation in Chicago was that we had a great-looking halo CME, a substantial number of
eager journalists, and no EIT images with which to determine whether the CME was directed or
directed toward or away from the earth. The BBC journalist evidently decided he (or she) knew
the answer when the SOHO scientists at the AAS meeting were still cratching their heads. The
fact that there'd been a press conference the previous morning
on the precipitous rise of the new solar activity cycle probably piqued the reporter's
interest. And the comment attributed to one solar physicist (my Lab head!) that a CME this big
was a "real planet buster" might have been too much for anenterprising newman/woman to resist.
Now, why was there a gap in the: http://www.spaceweather.com/java/solar-anim.html animation?
I honestly don't know. You should know, however, that www.spaceweather.com is a bit of a rogue
operation. First, it's got a .com Internet domain name, which means they can say anything they
want without having to be responsible to anyone at NASA (or the
taxpayers who pay us). On the other hand, the site is probably a good thing if NASA ever did
decide to try to "cover up" something of general interest, for precisely the same reason. I do
know the Public Affairs folks at NASA HQ have real heartburn over the ways in which the folks
at that Web site appear to steal credit for scientific work in which they were not
involved. (Frankly, it doesn't bother me all that much, because it's the science that the
taxpayers are paying for that's the important story, not who did it or where.)
If I had to guess --- and this is complete speculation --- as to why their site hadn't updated
images during the days in question, I would ascribe it to the same gotcha as bit the LASCO
folks: no one was in over the Memorial Day weekend, and somebody's "automatic" software broke.
So there's a few facts and an idle speculation, for what they're worth. My $0.02,
Joe Gurman
U.S. project scientist for SOHO
<cst@sdac.nascom.nasa.gov>
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