Saturday, January 22, 2011

Lottie Williams...lucky woman


Who is Lottie Williams? She is a very fortunate person to dodge the effects of some space junk.

"Jan. 22, 1997: Heads Up, Lottie! It's Space Junk!"

by

Tony Long

January 22nd, 2011

Wired

1997: Lottie Williams is strolling through a park in Tulsa, Oklahoma, when she sees a flash of light resembling a meteor. A short while later, she is struck on the shoulder by a piece of metal apparently from a disintegrating rocket, making her the only person believed to have been hit by a piece of space debris.

Although the fragment, which measured about 6 inches long, was never positively identified as having come from a rocket, NASA confirmed that the timing and location of the incident were consistent with the re-entry and breakup of a second-stage Delta rocket that fell to Earth after orbiting for several months. The main wreckage was recovered a couple of hundred miles away in Texas.

Williams was not injured. She was struck a glancing blow, and the debris was relatively light and probably traveling at a low velocity. It was also subject to wind currents, which mitigated the impact even further.

The amazing thing is that, given the amount of space junk that falls to Earth on a regular basis, there have been no other reports of someone being hit. Despite the veritable junkyard raining down on our planet — over a 40-year period roughly 5,400 tons of debris are thought to have survived re-entry into the atmosphere — the odds of actually being struck are infinitesimally small.

Components made of materials with high melting temperatures, such as stainless steel and titanium, are the likeliest candidates to survive re-entry into the Earth's atmosphere.

Predicting where the space debris will land is an inexact science, though, despite the ability to track a satellite's decaying orbit. The best that ground controllers can do is change a dying satellite's altitude, so its re-entry footprint — which can stretch hundreds or even thousands of miles — falls mainly over water or sparsely populated land.

Perhaps the most famous space junk of all time resulted from the demise of Skylab, the first U.S. space station, which orbited the Earth between 1973 and 1979. Increasing drag on the vehicle, caused partly by heightened solar activity, had a deleterious effect on Skylab's orbit, prompting ground controllers to bring it down early. They maneuvered Skylab into a re-entry footprint that would cause it to break up over the eastern Indian Ocean and western Australia.

It did, and several large chunks came to ground between the Aussie towns of Esperance and Rawlinna. Stan Thornton, a 17-year old living in Esperance, recovered some Skylab wreckage from the roof of his house and raced off to California, where the San Francisco Examiner was offering a prize of $10,000 (roughly $30,000 in today's money) to the first person who could deliver a piece of the space station to its newsroom.

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