Posted by One of the scariest things that could happen to Earth is to be bombarded with an asteroid or comet, as the potential for damage is incredible.
Well, it turns out that we get hit by tiny “space pebbles” all the time. Every time you see a shooting star, like the one below, it’s actually a very small rock, often the size of a mere grain of sand, streaking through the Earth’s atmosphere and disintegrating. The heat of vaporization is so intense that the object glows brighter than the stars in the sky, and — however briefly — these grains of sand and dust can outshine even the planets.
filled with this type of dust. But every once in awhile, every rare once-in-a-long-time, the Earth and an icy comet will wind up in the same place at the same time. When this happens, you get a collision. We’ve never seen this happen at Earth’s surface, although we know that this happened on the Moon in 2006 (it’s documented), and we did see a comet collide with Jupiter back in 1994. Take a look at the Moon impact below:
Well, something large — likely an icy rock like a comet — came into contact with the Earth in the early summer of 1908. The collision is known as the Tunguska event. Based on everything we’ve been able to reconstruct, it entered the Earth’s atmosphere, heated up, and — somewhere over Siberia — exploded due to the extreme heat. The devastation lasted for decades, as you can see from this 1927 picture from the ground beneath the explosion:
Trees were knocked down and burned for hundreds of kilometers, but there was no crater. Hence, this thing was probably made up of ice and/or carbon dioxide, things that expand and turn to gas when heated sufficiently. A build-up of pressure could easily cause such an explosion, and would explain the absence of a crater.
The thing that is perhaps surprising? This is common. The Earth gets hit by small meteoroids all the time. This phenomenon, known as an Air-Burst, is observed at least once a year by the US Air Force’s Defense Support Program. But very large ones, like the Tunguska event, should be rare, occurring only once every few hundred years. A nice open-and-shut case, and a great piece of physics to learn.
And then I read this, which made my stomach turn almost as hard as it did when I read that hikers had discovered Bigfoot. Yuri Lavbin — a scientist in self-proclamation only — claims that:
aliens downed the Tunguska meteorite 101 years ago to protect our planet from devastation. Yuri Lavbin says he found unusual quartz crystals at the site of the massive Siberian explosion. Ten crystals have holes in them, placed so the stones can be united in a chain, and other have drawings on them. “We don’t have any technologies that can print such kind of drawings on crystals,” said Lavbin. “We also found ferrum silicate that can not be produced anywhere, except in space.”
So. This man, who tried to sell this story in 2004 to Time Magazine and in 2007 to the UK’s The Register, is at it again. Let’s check out his crystals:
And a picture of Yuri himself, holding what he claims to be “a fragment of an alien spacecraft”:
Know what they look like to me? Rocks. I cannot put it better than Carl Sagan did so many years ago:
Extraordinary claims require extraordinary evidence.
And we’ve got bubkes here. Even UFO hunters think this is probably a hoax. I’ll take the physical, reproducible, scientific explanation every day of the week, thank you. And if I can help you see why that’s more interesting, more valid, and more right, I’m happy to do it.
And if you’re in the mood for more astronomical goodness, check out the latest Carnival of Space; there have been more than two years worth of them now!
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