Posted on 02/08/2003 7:09:43 PM PST by TLBSHOW
Edited on 04/13/2004 2:41:49 AM PDT by Jim Robinson. [history]
NASA officials said Friday they have asked experts in upper-atmosphere electric phenomena whether it is possible for such effects to occur at the altitude and weather conditions that the shuttle was flying through before it disintegrated.
But they said that so far they have found nothing in their investigation to indicate that the shuttle encountered such phenomena on re-entry. "There is nothing in the data stream . . . that would cause any concern on our part," said Ron Dittemore, NASA's shuttle program manager.
(Excerpt) Read more at sfgate.com ...
Red sprites, blue jets and elves are upper atmospheric optical phenomena associated with thunderstorms that have only recently been documented by using low light level television technology. These phenomena are collectively called Transient Luminous Events (TLE's)
Blue jets are a second high altitude optical phenomenon, distinct from sprites and first documented in 1994 (although pilots had earlier reported similar sightings). Blue jets are optical ejections from the top of the electrically active core regions of thunderstorms, but not directly associated with cloud-to-ground lightning. Following their emergence from the top of the thundercloud, they typically propagate at about upward in narrow cones of about 15 degrees, fanning out and disappearing at heights of about 25-30 miles (40-50 km) with a lifetime of a couple of tenths of a second.
Elves are disk-shaped regions of luminosity, lasting less than a thousandth of a second, which occur high above energetic cloud-to-ground lightning of positive or negative polarity. Elves most likely result when an energetic electromagnetic pulse (EMP) propagates into the ionosphere. Though they can be accompanied by sprites, the causative mechanism is of an entirely different nature. Predicted to exist in the early 1990's and discovered in 1994, elves got their name as an acronym for Emission of Light and Very Low Frequency perturbations due to EMP Sources.
Sprite halos are even more recently discovered. They are diffuse disk shaped glows that apparently precede sprites and propagate downward from about 50 miles to 40 miles (85 to 70 km) altitude and last about a millisecond.
Trolls, also recently observed, resemble blue jets, but are red and seem to occur after tendrils of vigorous sprites extend downward toward the cloud tops.
TIPPS (Trans-Ionospheric Pulse Pairs) are extremely intense pairs of VHF pulses originating from thunderstorm regions, but some 10,000 times stronger than sferics produced by normal lightning activity. They were first observed by the ALEXIS satellite.
Gamma ray bursts of short duration (about 1 millisecond) with terrestrial origin have been detected by the Compton Gamma Ray Observatory. They are observed to occur over thunderstorm regions, and their source is believed to lie at altitudes greater than 30 km.
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What an asinine choice of words....
Good, I'm not the only one who thought so.
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