An asteroid named 2009 TM8 just passed only 216,000 miles from Earth yesterday, racing at 18,163 mph. That’s closer than the moon. But don’t panic, there’ll be other opportunities!
In further evidence that space itself is an action movie (or at least that God watches Michael Bay movies), an explosion the size of the Pacific ocean has scarred Jupiter. Yes, the entire ocean. The explosion occurred on July 19 when an asteroid slammed into the planet, and although Jupiter has no solid ground the gas can still get thick enough for things like “impacts” and “KABOOM” to happen.
The Jupiter impact event is another big red line underscoring Stephen Hawking’s theory that one of the major factors in the possible scarcity of intelligent life in our galaxy is the high probability of an asteroid or comet colliding with inhabited planets. We know, for example, that Earth has had a major impact every 100 million years.
We have observed, Hawking pointed out in his lecture Life in the Universe, the collision of a comet, Schumacher-Levi, with Jupiter (below), which produced a series of enormous fireballs, plumes many thousands of kilometers high, hot “bubbles” of gas in the atmosphere, and large dark “scars” on the atmosphere which had lifetimes on the order of weeks. The July 19th event is a weak second place, but still totally awesome (and awesome if projected to a planet called Earth).
One of the most interesting things about the explosion is that it was detected by an amateur astronomer. We might have a lot of super-slick space-searching sensors, but there’s still a hell of a lot more space to watch than we have equipment to watch it - which is why Australian hobbyist Anthony Wesley was the first to see it. The information spread online, and Berkeley astronomer changed his plans for pre-booked time on the Hawaiian Keck II telescope, abandoning his planet-hunting to get a closer look. A much cooler use of internet communications than tweeting about sandwiches.
The resulting scar on the surface of Jupiter shows up as a dark patch in visible light, but a very bright spot in infrared, caused by a radical rearrangement of gases in the region of the detonation. The bright spot will also allow scientists to examine the motion of gases in Jupiter’s atmosphere, test theories developed during past impacts, and generally think “Wow, this stuff we do is pretty awesome, isn’t it?”
Many more tools will soon be brought to bear on this huge planetary event. Hubble will be getting in on the action, bringing its brand-new wide angle camera to bear, while Berkeley will be bringing laser guide stars to bear (artificial star-signals created in the atmosphere by laser beam, allowing the use of adaptive optic telescopes which can correct for the atmosphere’s effects on light). So even the tools being used to look at this are awesome.
As Stephen Hawking says, the general consensus is that any comet or asteroid greater than 20 kilometers in diameter that strikes the Earth will result in the complete annihilation of complex life - animals and higher plants. (The asteroid Vesta, for example, one of the destinations of the Dawn Mission, is the size of Arizona).
But back to Professor Hawking, he of black-hole radiation fame: How many times in our galaxy alone has life finally evolved to the equivalent of our planets and animals on some far distant planet, only to be utterly destroyed by an impact? Galactic history suggests it might be a common occurrence. Our cold comfort comes from the adjective “galactic” -that’s a hugely different time perspective that our biblical three score and ten.
Luke McKinney
Stephen Hawking: “Asteroid Impacts Biggest Threat to Intelligent Life in the Galaxy”
The NEO Code -Earth’s Hotspots Most at Risk Of Getting Hit by an Asteroid
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