Posted on 02/11/2003 5:20:37 PM PST by ex-Texan
Edited on 04/13/2004 2:41:49 AM PDT by Jim Robinson. [history]
Federal scientists are looking for evidence that a bolt of electricity in the upper atmosphere might have doomed the space shuttle Columbia as it streaked over California, The Chronicle has learned.
Investigators are combing records from a network of ultra-sensitive instruments that might have detected a faint thunderclap in the upper atmosphere at the same time a photograph taken by a San Francisco astronomer appears to show a purplish bolt of lightning striking the shuttle.
(Excerpt) Read more at sfgate.com ...
It wasn't the glue that was CFC based, it was the foam on the external tank. The stuff started falling off, well falling off more than it had before, when they switched to the non-CFC generated foam. The glue was something else, possibly the installers spitting in the glue to make it set faster, but that also made the bond weaker.
You guys are starting to sound like Captain Queeg reliving his discovery of a duplicate key to the food lockers. Well, Queeg was insane.
NASA is trying to fix the problem so it doesn't happen again. Avoiding "blame" is not an option.
Good heavens, I don't know if you guys are projecting, but not everyone has as corrupt souls as you. From what I can see, those engineers made engineering level assesments and they are still making them. You tinfoilers in the peanut gallery are amusing to a point, but after a while, your drumbeat of paranoia grows very tiresome.
Reminds me of some famous movie lines . . .
pay no attention to that man behing the curtain . . .
which are you going to believe, me or your lying eyes . . .
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Lightning between
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ILLUSTRATIONS: |
Since ancient times, lightning has both awed and fascinated people with its splendor and might. The early Greeks, for instance, associated the lightning bolt with Zeus, their most powerful god. And even after a modern understanding of the electrical nature of lightning developed, certain mysteries persisted. Many observers described luminous displays flickering through the upper reaches of the night sky. Some of these curiosities could be explained as auroras or weirdly illuminated clouds, but others were more baffling. In particular, pilots flying through the darkness occasionally observed strange flashes above thunderstorms. But the scientific community largely regarded these reports as apocryphal--until 1990, when John R. Winckler and his colleagues at the University of Minnesota first captured one of these enigmatic phantoms using a video camera. Their images revealed lightning of a completely new configuration.
Winckler's achievement ushered in a flurry of activity to document such high-altitude electrical phenomena. And hundreds of similar observations--from the space shuttle, from aircraft and from the ground--have since followed. The result has been a growing appreciation that lightninglike effects are not at all restricted to the lower atmospheric layers sandwiched between storm clouds and the ground. Indeed, scientists now realize that electrical discharges take place regularly in the rarefied air up to 90 kilometers above thunderclouds. It is remarkable that these events, many of which are visible to the naked eye, went undiscovered for so long. In retrospect, the existence of some form of lightning high in the atmosphere should not have come as a surprise to scientists. They have long known that well above the turbulent parts of the atmosphere, ultraviolet rays from the sun strike gas molecules and knock electrons loose from them. This process forms the ionosphere, an electrically conductive layer that encircles the earth. Large differences in voltage can exist between storm clouds and the ionosphere, just as they do between clouds and the ground. Impelled by such enormous voltages, lightning can invade either zone when the air--which is typically an electrical insulator--breaks down and provides a conductive path for electric currents to follow.
Because the atmosphere becomes less dense with increasing altitude, the lightning that happens at greater heights involves fewer air molecules and produces colors not seen in typical discharges. Usually they appear red and are only faintly visible. Thus, researchers must employ sensitive video cameras to record these events against the backdrop of the darkened night sky. The feebleness of the light given off and the transient nature of such emissions combine to present severe technical challenges to the researchers involved in studying these ghostly atmospheric events. Nevertheless, in just a few years investigators have made considerable progress in understanding them.
The newly discovered electrical events of the upper atmosphere fall into four categories. Two types of high-level lightning, termed sprites and elves, appear (despite their fanciful names) to be manifestations of well-understood atmospheric physics. The causes for the other two varieties, called blue jets and gamma-ray events, remain more speculative. But our research group and many others around the world are still amassing our observations in hopes of deciphering the physical mechanisms driving these strange occurrences as well. Until that time, we must admit something like the ancient sense of awe and wonder when we contemplate these curious bursts of energy that dance through the ethereal world between earth and space. Further Reading DISCOVERY OF INTENSE GAMMA-RAY FLASHES OF ATMOSPHERIC ORIGIN. G. J. Fishman, P. N. Bhat, R. Mallozzi, J. M. Horack, T. Koshut, C. Kouveliotou, G. N. Pendleton, C. A. Meegan, R. B. Wilson, W. S. Paciesas, S. J. Goodman and H. J. Christian in Science, Vol. 264, pages 1313-1316; May 27, 1994. PRELIMINARY RESULTS FROM THE SPRITES94 AIRCRAFT CAMPAIGN, 1: RED SPRITES. D. D. Sentman, E. M. Wescott, D. L. Osborne, D. L. Hampton and M. J. Heavner in Geophysical Research Letters, Vol. 22, No. 10, pages 1205-1208; May 15, 1995. PRELIMINARY RESULTS FROM THE SPRITES94 AIRCRAFT CAMPAIGN, 2: BLUE JETS. E. M. Wescott, D. Sentman, D. Osborne, D. Hampton and M. Heavner in Geophysical Research Letters, Vol. 22, No. 10, pages 1209-1212; May 15, 1995. ELVES: LIGHTNING-INDUCED TRANSIENT LUMINOUS EVENTS IN THE LOWER IONOSPHERE. H. Fukunishi, Y. Takahashi, M. Kubota, K. Sakanoi, U. S. Inan and W. A. Lyons in Geophysical Research Letters, Vol. 23, No. 16, pages 2157-2160; August 1, 1996. Related Links Sprites, Q-Bursts and Positive Ground Strokes Walter Lyons' Handy Weather Answer Book
The Authors STEPHEN B. MENDE, DAVIS D. SENTMAN and EUGENE M. WESCOTT have spent much of their time during recent years investigating curious electrical activity of the upper atmosphere. Mende received a Ph.D. in physics from Imperial College at the University of London in 1965. From 1967 to 1996 he worked for Lockheed Palo Alto Research Laboratory. Mende is currently a fellow at the space sciences laboratory of the University of California, Berkeley. Sentman studied space physics under James Van Allen at the University of Iowa, where he earned his doctorate in 1976. After 14 years at the University of California, Los Angeles, Sentman joined the physics department at the University of Alaska-Fairbanks, where he now serves on the faculty. Wescott received a Ph.D. in geophysics from the University of Alaska-Fairbanks in 1964. He worked for three years at the National Aeronautics and Space Administration Goddard Space Flight Center in Maryland before returning to the University of Alaska-Fairbanks as a professor of geophysics. |
SPRITES are high-altitude luminous flashes that take place above thunderstorms in a part of the atmosphere called the mesosphere. Although sprites are usually rare, some storms can spawn them frequently. Typically the upper parts of clouds are charged positively and the lower parts negatively. Most often, it is the negative base of the cloud that flashes to the ground. But at times the upper, positive part can discharge directly to the earth, producing a lightning flash of exceptional intensity. About one out of 20 such positive cloud-to-ground lightning bolts are sufficiently energetic that they spawn sprites. These examples, recorded from the ground with a monochromatic video camera, have been colorized to match a color image obtained from an aircraft.
LIGHTNING (below, left) usually carries negative charge from the base of a cloud down to the earth. Sometimes powerful strokes (center) cause the positive charge that had built up near the top of the cloud to disappear abruptly. The large electrical field (gradation in color) created between the cloud top and the ionosphere pulls electrons upward, where they collide with gas molecules. If the electrical field is sufficiently strong and the air sufficiently thin, the electrons will accelerate unimpeded and reach the velocity needed to transfer their kinetic energy to the electronic structure of the molecules with which they collide, raising such molecules to an "excited state." The excited molecules give away their newly acquired energy by the emission of light, causing sprites (below, right). They typically span from 50 to 90 kilometers altitude.
Nobody threw away anything. And you know it.
NASA Now Doubts Tank Foam Debris Doomed Columbia
By JOHN M. BRODER
HOUSTON, Feb. 5 — NASA officials expressed doubt today that a piece of foam from the external fuel tank that struck the shuttle Columbia during its liftoff could have led to the destruction of the ship.
On Monday, officials identified damage caused by the impact during the launching on Jan. 16 as a prime suspect in the series of failures that led to the Columbia's breakup over Texas on Saturday.
But today, Ron D. Dittemore, the shuttle program manager, said that he and other NASA officials did not believe that the lightweight insulating material could have caused sufficient damage to be a primary cause of the shuttle's disintegration.
"Right now, it just does not make sense to us that a piece of debris would be the root cause for the loss of Columbia and its crew," Mr. Dittemore said at a briefing this afternoon at the Johnson Space Center here. "We don't believe it's this chunk of foam. It's got to be something else that we don't know about."
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This is gross incompetence by NASA. They are dismissing the most obvious suspect out of hand, on speculation alone, without the substantiation to do so. That, in the jargon, is throwing it away. There is also strong motivation by NASA management to have the root cause be an act of God and not the foam.
Keep me posted. However, until more conclusive evidence comes up I believe that the space shuttle disaster was due to detachment of some of its tiles.
The angel Michael. Archangel of fire. Angel of the sun.
You think he had something to do with the shuttle?
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