About Seth Shostak: Seth Shostak is an American astronomer, currently Senior Astronomer and Director, Center for SETI research.
There's no doubt that the Moon is more than a handy night light and a hair restorer for werewolves. It's responsible for the substantial amplitude of earthly ocean tides. These are of obvious influence if you're a geoduck, a type of clam that people ...
Recent results from astronomers who study the occasional gravitational lensing of unknown worlds by intervening stars suggest that orphan planets could be at least as numerous as the stars. In other words, there could be hundreds of billions of orpha...
Are two eyes, four appendages and an upright posture really essential for any creature that can ace the galactic SAT's? Maybe not. In fact, I'd venture that any aliens we ever detect or (less likely) encounter will look quite different than this self...
The era during which only governments could put hardware on the Moon is coming to an end. There are 26 private teams competing for the $30 million Google Lunar X-Prize - to be awarded for sending a robotic spacecraft to this nearby world that can roa...
Admittedly, it would take industrial-grade chutzpah and a massive dose of malevolence for anyone to bulldoze the spot where Neil Armstrong stepped off the Eagle lander. But even innocent visits could be damaging.
Star Trek's genial premise is that the cosmos is flush with intelligent species, and our descendants will interact with them face-to-face, thanks to warp drive and some winsome space cadets.
Estimates are that at least 70 per cent of all stars are accompanied by planets, and since the latter can occur in systems rather than as individuals (think of our own solar system), the number of planets in the Milky Way galaxy is of order one trill...
Despite tantalizing suggestions of fossilized microbes in meteorites, puzzling and possibly biogenic methane gas in the martian atmosphere, and a long-standing controversy over the Viking lander experiments of nearly 40 years ago, there's still no Ex...
When it comes to brains, size matters. It's not all that matters, of course. Whales and dolphins have brains that are larger than humans', but few of the flippered and fluked set win tenure at Stanford. Our brains are the largest in proportion to bod...
We're not just any star stuff, most of which is humdrum hydrogen and listless helium. Our bodies include fancier ingredients like carbon, oxygen, nitrogen, phosphorous, and a few other herbs and spices.
Are we the only members of the Galaxy that can actually understand what a galaxy is? Could Homo sapiens really be the pinnacle of Creation - the cleverest critters in the cosmos? If we learn the answer is 'no,' that would affect our philosophies fore...
Charles Darwin sailed around the world for two years on the 'Beagle,' and he had quite a bit of interest in things like the iguanas of the Galapagos, even though they were primitive compared to your average Englishman.
If aliens are really hanging out in our 'hood, it's hard to imagine any other fact more worthy of study. If not, then why does such a large fraction of the populace insist on believing they're here?
I've often fantasized about visiting the Bahamian beach where Columbus first stumbled ashore in 1492. Sadly, no one knows where that beach is. In fact, no one's even sure which island Columbus first encountered (there are three candidates). It's a pi...
It's always a tough call deciding whether, as a scientist, you should argue publicly with the creationists. It's a dilemma that I encounter frequently in another subject area: Does it make sense to bandy words with someone from the UFO community?
Imagine if the dinosaurs had tried picturing the rulers of their planet 100 million years hence. They'd undoubtedly envision these creatures as... dinosaurs! Conceiving of aliens as polished versions of ourselves is appealing, but unconvincing.
Of course there is still unexplored terrestrial territory, but most of it is waterlogged. Submersed secret places, such as the Challenger Deep, which today lure hi-tech adventurers like Richard Branson and James Cameron, will undoubtedly provide welc...
Junk, redundancy, and inefficiency characterize astrophysical signals. It seems they characterize cells and sea lions, too. These biological constructions have lots of superfluous and redundant parts, and are a long way from being optimally built or ...
Five centuries from now - barring unimaginable catastrophe - the moon will be developed real estate. There's economic incentive to exploit the moon - the helium-3 will be useful in powering fusion reactors, and the rare earth elements could supplant ...
'E.T.' was far-fetched. 'E.T.' was this wimpy-looking kid that came to Earth to pick some plants, but he came from the Andromeda Galaxy to do that.
Some pundits have proposed that the aliens have come here to breed with us. Apparently, too much bike riding or something similar has rendered them incapable of reproducing within their own species. But do extraterrestrial infants toddle through your...