By all accounts, Stephen Hawking is the smartest man on Earth, an astrophysicist so brilliant I can’t understand how he puts up with the rest of us. I’m sure he could read our minds, if he wanted to put up with such trivia, or just kill us with a withering stare.

Hawking has just speculated in a television documentary that, mathematically speaking, the odds are good that extraterrestrial life exists. And not simply alien grubs scuttling about for water beneath a Martian rock, but beings who pilot massive space ships through the universe. Aliens who have depleted the resources of their own planets in building these amazing vehicles, and are perhaps now in search of new worlds to plunder. And here is Earth, a bright-blue jewel glittering in our modest galaxy, wandering in the darkness like a tourist in a bad neighborhood, about to be mugged. It’s best to keep a low profile, Hawking advises. Don’t make eye contact. In our world’s own history, the technologically advanced civilizations have generally crushed lesser populations. Columbus’ arrival in the New World didn’t work out well for the natives, Hawking notes.

So Hawking has gone Robert A. Heinlein on us. And again, history is working against us. Our radio transmissions are slowly spreading through the cosmos. The sensitive equipment on the monstrous alien ships may be picking them up as you read this. Imagine what they’re seeing and hearing. The Three Stooges. American Idol. Nixon’s “Checkers” speech. Old Washington Senators baseball games. The Hindenburg disaster.  F Troop and Hogan’s Heroes. Congress on C-SPAN and Space Ghost cartoons. Our future masters should find Orson Wells’ 1938 radio broadcast of War of the Worlds encouraging enough. We are a culture of incompetence, filled with fearful and conniving souls, and likely candidates for elimination.

I’m afraid there are not enough episodes of Masterpiece Theatre out there to save our asses.

If only we could see them coming. Peer into the future. Could Hawking have some help for us there?  Time travel may be possible, he says. I agree. My garage is a time machine. I was just in there yesterday, and found a 1985 Mazda RX-7, a two-year-old bag of charcoal, a horse’s skull, an Obama-Biden lawn sign (I’m saving that for 2012), a cool-looking tree stump, a garden hose that I might patch one day and, nailed to the wall, license plates from every car I’ve owned.

Yet, while pondering Einstein’s ideas of time moving faster in some places than others, Hawking’s massive brain over-thinks the question. “All you need is a wormhole, the Large Hadron Collider or a rocket that goes really, really fast,” he wrote in the London Daily Mail. Poking about my garage, I found neither of the last two items stored under a dusty tarp behind the lawnmower. And wormholes? Hawking defines them as “tiny shortcuts through space and time that constantly form, disappear, and reform within this quantum world. And they actually link two separate places and two different times.”  Not quite the same wormholes I find in the wall studs of the 83-year-old building.

Time travel is one of the most intriguing ideas in humankind. Being somewhat mordant in nature, we’ve all wondered what it might have been like on the deck of the Titanic on the night of April 14, 1912, so long as we can shove Leonardo DiCaprio out of the way, step back into the time machine and be whisked away to safety by the theory of relativity as the ship slips beneath the waves. And of course I’d like to step into the future, the not too distant future, to the night some guy with two beers in him is driving his pickup truck home through the Pacific Northwest woods and hits and kills a Bigfoot, thus proving it exists.

Hawking’s own time travel wish list is both altruistic (watching Galileo examining the stars with his telescope) and voyeuristic (visiting Marilyn Monroe in her prime).

Alas, his Peeping Tom urges are limited by his technology. Hawking’s time machine theories, he admits, allow humans to only move forward into time. So my swayback-roofed garage is superior to his Hadron Collider. The smartest man on earth didn’t think of that. “Perhaps I’d even travel to the end of the universe to find out how our whole cosmic story ends,” he says. Go ahead, Mr. Hawking, Super Brain. Travel to the end of the universe. Then how are you gonna get back here? I’ll tell you how it ends, anyway. Badly. It’s in all of the science fiction.