Haag says hundreds of meteorites fall every year, but only a handful of them are actually seen falling through the air.
So there may be millions of meteorites just lying around waiting to be found. But why would anyone want to go looking for them? Well, one reason is their commercial value. In today's meteorite marketplace, these visitors from the stars can net anywhere from a few dollars to millions, depending on the size, quality and rarity of the specimen.
To zero in on the location of a meteorite, Haag depends on eyewitness accounts, news reports and, if the sighting is an older one, library research. When he hears about a new find and travels to the location, one of the factors he deals with is the question of who owns the rock. He says people often come out of the woodwork, claiming the rock was originally theirs.
"What happens is, somebody will find one, and because it has no title -- until someone picks it up -- it suddenly now has ownership," he said. "The problem has always been immediate, at the location where it fell: who owns that rock?"
It's still a rare event to even find a meteorite, said Carl Francis, curator of the Minerological Museum at Harvard University.
"You start with a planet that gets broken up. Then, some of these pieces have to cross the orbit of Earth and get attracted in by its gravity -- so they don't miss it. And then, they have to not burn up entirely, then they have to hit land -- and not the 71 percent of the Earth's surface that's covered with water -- and then they have to be found by somebody, recognized as meteorites, and then studied," he said. "You've got a lot of steps, so a studied meteorite is a really, really rare thing."
Haag has learned over the years that rocks sitting somewhere they have no geological business being -- on a dry lake bed or in a field -- are likely meteorite candidates. But some are not so easy to find, such as those that wind up buried deep in the ground by the force of their impact.
A certain amount of adventure and risk comes with the territory of worldwide meteorite sleuthing, and Haag has had his share.
"I've been in some pretty remote places looking for these things," he said. "In the jungles of Mexico I ran into landslides, bandits and roads so narrow that my truck nearly went over. … I've also walked, unknowingly, through land mines."
His most recent meteorite hunt took him to Peru, near Lake Titicaca, in November to the crater made by a swarm of meteorites, most of which vaporized, leaving only a few pounds behind for Haag to find.
"It was a stone meteorite that was breaking apart real close to the ground, and it created a huge crater, blowing dust in the air, terrifying people and killing animals," he said.
As he always does before packing his bags and grabbing his passport, Haag researched this meteorite fall.
"I immediately left for the airport, to Miami, and went right down there, and I got there pretty much ahead of everybody else, working with some people from Peru who spoke the native Inca language -- it was really a great adventure."
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