Seth Shostak
Seth Shostak
Seth Shostakis an American astronomer, currently Senior Astronomer and Director, Center for SETI Research...
NationalityAmerican
ProfessionScientist
CountryUnited States of America
either exist habitable hot liquid metric noxious planet solid surface type usual water whether worlds
The usual metric for whether a planet is habitable or not is to ascertain whether liquid water could exist on its surface. Most worlds will either be too cold, too hot or of a type (like Jupiter) that may have no solid surface and be swaddled in noxious gases.
anyone ask billion both existence kids legitimate love pose roughly seems
'What was there before the Big Bang?' That's a question that both kids and adults love to pose to anyone who seems sympathetic. After all, if the universe has only been around for roughly 14 billion years, isn't it legitimate to ask what was in existence before the mother-of-all-events cranked up the cosmos?
alone believe billion credulity dead exist frequency galaxy life math planets roughly seems support takes worlds
The math is dead simple: it seems that the frequency of planets able to support life is roughly one percent. In other words, a billion or more such worlds exist in our galaxy alone. That's a lot of acreage, and it takes industrial-strength credulity to believe it's all bleakly barren.
asteroid ball billion cosmic countless debris existence four hit infant large natural system took
The Moon is a ball of left-over debris from a cosmic collision that took place more than four billion years ago. A Mars-sized asteroid - one of the countless planetesimals that were frantically churning our solar system into existence - hit the infant Earth, bequeathing it a very large natural satellite.
bit cosmic existed humans instance intelligence last machinery nearly percent says time unless
Humans have existed only for the last 0.001 percent of cosmic time. All of which says that - unless the Homo sapiens brain is the one-and-only instance of cogitating machinery - nearly all the intelligence that's out there is beyond our level. And that intelligence is more than just a little bit beyond.
billions creatures dependent ebb exist life raised tides
Even if the Moon didn't exist - even if it had been vaporized billions of years ago by cantankerous Klingons - there would still be (somewhat lower) tides raised by the Sun. For creatures dependent on the oceans' ebb and flow, life could go on.
among developed few mold number proved science societies spread useful zero
Very few societies on Earth developed science as we know it today. On the other hand, the number is not zero - the Greeks, the Chinese, and the Maya did, among others. Once invented, science proved so useful that it spread like mold on a petri dish.
both bright dominate forget night percent rare stars
We've accounted for 95 percent of all the stars in the Milky Way. The other 5 percent are big, bright stars - the kind that dominate the night sky, but are lamentably both rare and short-lived. If biology's your thing, you can forget those guys.
bad coming earth edison films invented involved moving
When I was a kid, which was just after Edison invented moving pictures, there were films that involved aliens coming to Earth for bad purposes.
allowing continuing few five perhaps pound thousands
Our brains are continuing to evolve, and perhaps a few tens of thousands of years from now, our descendants will walk around with five pound brains, allowing them insights that we can't imagine.
currently life might planets plate rich scarcely sports venus
Planets that don't currently sport plate tectonics, such as Venus and Mars, are scarcely habitable. Tectonics might be a requirement of any world that aspires to a rich diversity of life.
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Mars still remains the astrobiology community's number one choice for 'nearest rock with life,' but there are many researchers who argue that the moons of Jupiter are better bets. In particular, Europa, Ganymede, and Callisto are all thought to hide vast oceans of liquid water beneath their icy, outer skins.
home intelligence might stay
I think there's a lot of intelligence out there, but that's just my guess. Question is: Are they peaceable or hostile? You could say that the peaceable ones are just going to stay at home and play with their Nintendos, so if you do meet any of them, they might be hostile.
brains build good inadequate might perhaps
Sure, our three-pound brains might be inadequate to understand the universe. But perhaps they're just good enough to build something that can.