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(meteorobs) Tr: [ASTRO] Giant Snowballs In Space? No, Says Reseacher
Hi all,
From the Astro list, minicomets we were talking about last May
----------
> De : Ron Baalke <BAALKE@kelvin.jpl.nasadot gov>
> A : astro@lists.mindspring.com
> Objet : [ASTRO] Giant Snowballs In Space? No, Says Reseacher
> Date : jeudi 11 décembre 1997 02:55
>
> University of Washington
>
> Contact: David Brand
> dbrand@u.washingtondot edu
> (206) 543-2580
>
> December 9, 1997
>
> Giant Snowballs In Space? No, Says Researcher, They're Simply
> Black Snow On The TV Screen
>
> San Francisco -- When University of Iowa space physicist Louis
> Frank presented his evidence last May, he had much of the science
> community shivering with anticipation. He claimed to have
> discovered 20- to 40-ton cosmic snowballs, the size of houses,
> pelting the Earth at the rate of 30,000 a day. What's more, Frank
> presented images he had captured of the giant snowballs.
>
> But the snowballs may not exist. University of Washington
> geophysicist George Parks has analyzed Frank's ultraviolet (UV)
> camera images and has concluded that the white snow in space is no
> more than black "snow" on the television screen.
>
> After a close analysis of one hour of data supplied by Frank,
> Parks says he and his collaborators are certain that Frank has
> been looking at "instrument noise." It is very similar, says
> Parks, "to the static you hear on your hi-fi."
>
> Frank and Parks will debate the real vs. phantom snowballs here
> today at the fall meeting of the American Geophysical Union in San
> Francisco (Dec. 9 at 4 p.m.).
>
> Frank first proposed his theory of the cosmic snowballs --
> actually small comets -- in 1986, but the idea was widely
> discredited. Then, earlier this year, he presented evidence from
> the Polar satellite, which carries an instrument that can produce
> both UV and visible light images. Frank compared the same spots on
> both types of image and concluded that these were clear evidence
> of the existence of the comets.
>
> Parks says that at first he was "agnostic" towards Frank's data.
> But when he saw the far more detailed images from the Polar camera
> he became suspicious. It was simply unlikely, he says, that the
> clusters of spots on the images could have been caused by
> snowballs in space. Parks began an analysis of his own images
> taken with the Ultraviolet Imager (UVI) on the NASA Polar
> satellite. There he found the same dark spots that Frank had found
> on his images.
>
> He grew even more uneasy about Frank's analysis when he found that
> the UVI had recorded the same dark spots while pointed at a UV
> light in the laboratory.
>
> When Parks began a minute examination of the images, made by
> breaking the clusters of spots down into tiny picture point, or
> pixels, he found statistical evidence that he was seeing not real
> events, but what he calls an "instrument artifact."
>
> After Parks had detailed his analysis in an article for
> Geophysical Research Letters, Frank released one hour of data that
> overlapped with Parks' UVI images. Parks has made a comparison of
> the two and now believes, even more emphatically, that Frank has
> been attempting to interpret background noise.
>
> What is causing the spots on the images? Park blames the very
> complexity of the cameras themselves, which consist of a number of
> parts, including optics, an image intensifier that includes a
> device for multiplying electrons, a TV screen and a
> light-gathering charge-coupled device. Parks suspects that the
> dark spots change character as the camera's high voltage is
> varied.
>
> Parks claims that Frank has taken complex images and selected only
> one tiny area as evidence of the comets' existence. "He nevers
> shows the full image because it always looks corrupted by noise,"
> he says.
>
> Is Parks then denying the existence of cosmic snowballs? "The
> burden is on Frank, he's got to prove they exist," Parks says. "He
> is seeing things that are scientifically not permitted. It would,
> for example, be easy for me to say these dark spots are UFOs, but
> it would be up to me to prove it."
>
> ###
>
> Parks and Frank will hold a press conference at 9 a.m., Dec. 9, in
> Room 112, Moscone Center, San Francisco. They can be reached at
> the AGU press room, (415) 905-1007.
>
> Parks is staying at the Holiday Inn Union Square, (415) 398-8900.