Geoff Notkin, 50, star of the the reality TV show “Meteorite Men,” has a nose for space rocks. Wielding a metal detector, the British Notkin and his American sidekick, Steve Arnold, bop from Iowa to Australia to Poland to Russia in search of otherworldly treasure. When they make a find, they jump up and down and yell — and who wouldn’t? The rarest meteorites offer clues to the history of the solar system, while even the relatively common types are worth more than a few bucks to space-rock enthusiasts. Now in its third season, “Meteorite Men” appears on the Science Channel.

— Brian Vastag

Where does your meteorite obsession come from?

I was a very avid rockhound from age 5 or 6, always out in quarries looking for fossils. And my father used to wake me up in middle of the night, in winter, and bundle me up and say, “Geoffrey, look, you can see the rings of Saturn.” This was wondrous to me as a kid, that you could examine alien worlds from your garden. It was that plus my love of rocks that led to it.

And how did you turn this obsession into a full-time job?

It started as a hobby and a passion and then became a business and then became a television show. I was an avid collector for years, and I had a few [meteorite] dealer friends. For a while I thought, “This is my passion. I want to keep it a hobby and separate from business.” But I became more and more pulled into the field. My first commercial ventures were documenting [museum and private] collections and building Web sites where the public could view meteorites. I realized I was spending so much time on meteorites [that] I should focus all of my energy there.

How do you hunt for meteorites?

The most obvious strategy is to look for fragments following a witnessed fireball. We have large meteor events worldwide several times each year. Some will burn up entirely in the atmosphere and won’t make it to the ground. But in some cases, witnesses have clearly seen pieces spiraling off. There is then a complex process to determine where pieces might have fallen. Numerous times we’ve been lucky to get surveillance video from closed-circuit cameras and even police cars. Once we’ve got our best guess, we go around knocking on doors.

Do you also look for space rocks that fell to Earth long ago?

The part of meteorite hunting that interests me the most is researching historic sites, places where gold prospectors, hunters and farmers found them in the past. We examine these old tales. Some are apocryphal. Some we read about in old newspapers. We then check land records and show up and say, “You know, you might have treasure here — a piece of space buried.” Four times out of five, they have no idea meteorites are on their land.

We then make a friendly deal. We do the work, and we share the money from the find. We’ve become great friends with some of the landowners. We worked on one farm in Kansas for five years off and on. Every evening, this friendly farmer would walk out with a shovel just before sunset to check on us.

How many have you found?

Thousands over the last 17 years. The biggest was 273 pounds, in a farmer’s field in Kansas. Steve and I have been to sites where we’ve found hundreds of fragments in a day. On other expeditions, we might find just one piece in three weeks.

You’re a meteorite dealer. Doesn’t this conflict with studying the finds?

There are a small number of people who work with meteorites full time outside of academia, a small network of dealers. And we have a wonderful symbiotic relationship with meteorite scientists. If we find something of scientific interest, the first thing we do is take it to Laurence Garvie, the collections manager at the Center for Meteorite Studies at Arizona State University. It’s in everybody’s interest to donate important pieces to science. It’s the right thing to do. Meteorites are the geology of our solar system.

Why do people become enthralled with meteorites?

I think it’s the wonder. We all crave amazement and delight in our lives. When people realize they can hold in their hand something that’s actually traveled from outer space, there’s a lot of joy and amazement in that.