Each year, thousands of UFOs are sighted and reported, which is an impressive tally of unidentified aerial phenomena. Surveys show that roughly one-third of the populace believes that at least some of this sky show is due to extraterrestrial spacecraft, here to probe our airspace and, when that proves boring, our bodies.Seth Shostak
The cosmos is three times as old as Earth. During most of creation's 14 billion year history, our solar system wasn't around. Nonetheless, the early universe still had the right stuff for life, and contained worlds that were just as suitable for spawning biology and intelligence as our own.Seth Shostak
The majority of my UFO diet consists of reports describing suspected encounters. This is not surprising, as there are thousands of sightings annually. The emailer has seen something unusual in the sky that he interprets as probable evidence of alien presence.Seth Shostak
The principal reason for the universe's poker face is that its constituents are far away. Stars careen through space, and galaxies spin at speeds thousands of times faster than a jet plane. But given their distance, you'd need the patience of Job to notice much change in their appearance or position.Seth Shostak
The Moon stabilizes Earth's obliquity. Well, almost. The tilt actually varies between 22 and 24.5 degrees - and the variation is enough to induce such environmental inconveniences as the occasional ice age. Without the Moon, it might be much worse.Seth Shostak
You may not see massive UFO exhibits at your local science museum, but there's no dearth of saucer stories infesting my email. Every day, I receive several reports of alien sightings, extraterrestrial plans for Earth, and agitated screeds about the reluctance of scientists to take the whole subject seriously.Seth Shostak
Three-fourths of the universe is hydrogen, and oxygen is incredibly abundant, too. So H2O is something you can find nearly everywhere.Seth Shostak
It's hard to imagine anything more interesting than learning how we're woven into the enormous tapestry of existence. Where did our universe come from? How special is our world, and how special are we? We allocate tens of billions of dollars annually to NASA, NSF and academia in search of the answers.Seth Shostak
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 trillion.Seth Shostak
According to 'Star Trek' mythos, Starfleet Command - operational headquarters for a flotilla of craft that keep the cosmic peace - is located in San Francisco's Presidio, in the shadow of the Golden Gate Bridge (still carrying traffic, even in the 23rd century).Seth Shostak