2019年1月22日星期二

稱為'毀滅之神'的小行星有很好的機會成就這事

稱為'毀滅之神'的小行星有很好的機會成就這事
Asteroid Named for God of Destruction Has Good Chance of Causing It

If you name your kid “Killer,” you should be prepared to accept the consequences … or at least his therapy bills (and if Killer’s a she, you need help as well). So it should come as no surprise that an asteroid named for an ancient Egyptian god of destruction, darkness and evil (apparently, in the case of asteroids, those are not redundant) is actually being predicted to cause destruction, darkness and evil. Not only that, the estimated time of arrival is a mere few decades from now. Will there be time to send a force of good, light and wholesomeness (with a nuclear warhead, of course) to stop it?
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“The [asteroid’s] approach causes a significant scattering of possible trajectories, among them trajectories indicating convergence in 2051. Further orbital resonance reentries contain a great number (about one hundred) possible collisions between Apophis and the Earth, the most dangerous of them in 2068.”
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While you may not be concerned about 99942 Apophis, Russian scientists are. In a new report to be presented at the 43rd Korolev Readings on Cosmonautics (an annual scientific forum dedicated to the memory of Sergei Korolev – a rocket engineer considered to be the Soviet Union’s Robert Goddard and the father of practical astronautics), researchers from St. Petersburg State University are predicting Apophis will come within 16 million km (10 million miles) of Earth in 2044, within 760,000 km (472,000 miles) in 2051, within five million km (3.1 million miles) in 2060, and within 100,000 km (62, 000 miles) in 2068. (For reference, the Moon is 385,000.6 km (239,228.3 mile) from Earth).

That doesn’t sound so bad, right? It gets worse, according to Sputnik News, (interesting coincidence — Sergei Korolev worked on Sputnik 1, the first artificial satellite.) Apophis is also making a very close pass by Earth in 2029 (within 37,600km (23,363 miles) and that one will determine if and when the asteroid will hit the Earth on a future (and last) trip. That’s when Apophis could pass through a tiny gravitational keyhole which would alter its trajectory enough to cause a collision on the future pass in 2036.

Yes, we’ve heard about this many times before since it was discovered in 2004 (when initial observers predicted a 2.7% chance that it would hit the in 2029. Subsequent revisions in the calculations eliminated the probability for a hit in 2029 but came up with the keyhole possibility instead. What kind of impact would this 350 meter (1,150 feet) diameter rock have? The Sentry Risk Table estimates that Apophis would make atmospheric entry with 750 megatons of kinetic energy. For comparisons, the Siberian Tunguska event in 1908 was in the 3–10 megaton range and the biggest hydrogen bomb ever exploded was around 57 megatons.

While anti-conspiracists say the odds of an Apophis hit are so low that there’s no need to even be talking about it, Russians scientists certainly are, as evidenced by the Korolev Readings presentation. And the “force of good nuke versus evil asteroid” is a real option studied by researchers at Tomsk State University in Siberia. Why are the Siberians so worried? Can asteroid strike twice in the same place? For that matter, why are the Russians? Do they know something we don’t? Or something NASA won’t tell us?

There seem to be reports monthly of asteroids that pass very close to the Earth without warning. Is it really hand-wringing or fear-mongering to worry about a real asteroid with a known schedule and a distinct possibility of hitting Earth?

Especially one named after the god of destruction?


https://mysteriousuniverse.org/2019/01/asteroid-named-for-god-of-destruction-has-good-chance-of-causing-it/






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