"He [Democritus] said that the ordered worlds are boundless and differ in size, and that in some there is neither sun nor moon, but that in others, both are greater than with us, and yet with others more in number. And that the intervals between the ordered worlds are unequal, here more and there less, and that some increase, others flourish and others decay, and here they come into being and there they are eclipsed. But that they are destroyed by colliding with one another. And that some ordered worlds are bare of animals and plants and all water." -- Hippolytus, priest, 2nd century
2400 years after Democritus, mainstream scientists are finally catching up with 5th century (B.C.) thought.
Clara Moskowitz: Two Worlds Collide in Deep Space. (Hat tip: Jeffery Keown).
Two distant planets orbiting a young star apparently smashed into each other at high speeds thousands of years ago in a cosmic pileup of cataclysmic proportions, astronomers announced Monday.If the universe is over 12 billion years old and there are more than 10 trillion planets, how rare can it be?
Telltale plumes of vaporized rock and lava leftover from the collision revealed its existence to NASA's Spitzer Space Telescope, which picked up signatures from the impact in recent observations.
The two-planet pileup occurred within the last few thousand years or so - a relatively recent cosmic timeframe. The smaller of the two bodies - a planet about the size of Earth's moon, according to computer models - was apparently destroyed by the crash. The other was most likely a Mercury-sized-planet and survived, albeit severely dented.
"This collision had to be huge and incredibly high-speed for rock to have been vaporized and melted," said Carey Lisse of the Johns Hopkins University Applied Physics Laboratory in Maryland, lead author of a paper describing the findings in the Aug. 20 issue of the Astrophysical Journal.
Researchers believe the planets were moving at about 22,400 mph (10 kilometers per second) before the crash. The violent wreck released amorphous silica rock, or melted glass, and hardened chunks of lava called tektites. Spitzer also spotted large clouds of orbiting silicon monoxide gas created when the rock was vaporized.
"This is a really rare and short-lived event, critical in the formation of Earth-like planets and moons," Lisse said. "We're lucky to have witnessed one not long after it happened."