It was a choice between Las Vegas or "the big hole in the ground" for Mike Young, a British tourist standing on the rim of a giant crater in the Arizona desert.

"The hole won," he said, gazing down at a windswept bowl in the desert floor where something big and fast rocketed from outer space and slammed to Earth about 49,000 years ago.The result of this sudden and violent encounter with the cosmos is called Meteor Crater National Monument, a place that draws 240,000 visitors to see - let's face it - a hole in the ground.

"This was a single, sudden event," Young said of the crater, which is unlike the Grand Canyon that was formed by millions of years of erosion. Another British visitor, Susan Winterburn, said it's the first meteor crater she's ever seen and she hopes she never sees another.

"If another came, it would kill millions, wouldn't it?" she asked.

That is part of the fascination of Meteor Crater - knowing that the Earth is under bombardment by unexpected celestial objects and is likely to be clobbered again some day.

"They come whizzing by us," says Dr. David Roddy, a geophysicist for the U.S. Geological Survey in Flagstaff, speaking of more than 60 asteroids known to cross Earth's orbit.

In fact, said Roddy, large meteorites hit the Earth about once every 50,000 to 100,000 years.

While contending that the probability of a life-destroying asteroid striking the Earth is low, the American Institute of Aeronautics and Astronauts has urged the government to set up a program to identify asteroids that threaten to crash into Earth.

"It would certainly benefit all nations to know when such an event might occur (and) warn those who could be affected," Vice President Dan Quayle, chairman of the National Space Council, said in a speech last June to the institute.

But Meteor Crater, 35 miles east of Flagstaff in northern Arizona, is much more than the geological record of a celestial encounters.

It has the distinction of being the place where human understanding of such cataclysmic events was born, in large part because of the stubbornness of one man who was ridiculed by experts.

Most people know Meteor Crater as a tourist attraction, where they pay $6 for a ticket and spend an hour in a museum that illustrates how a nickel-iron meteorite weighing around 300,000 tons and traveling 12 miles a second punched a hole in the ground.

It was over in seven seconds, but left a crater 570-feet deep and almost a mile across.

Owned privately, Meteor Crater Enterprises, Inc., is open to all scientists as a natural laboratory because of what it can and does reveal about the creation of the universe.

"The collision of bodies in space is one of the most fundamental processes that occurs," explained Roddy, who conducts research at the crater and helped design the museum. "We wouldn't have a planet without impacts, or a solar system."

Scientists say the formation of stars and planets from celestial gas and dust essentially is the dynamics of collision and gravitation attraction over 10 billion years. At Meteor Crater, scientists determined that the age of the solar system and this planet is 4.5 billion years.

Even the Earth's biological evolution is linked with meteor strikes.

Some scientists suspect that the planet was smashed by an asteroid or comet, triggering climatic changes 65 million years ago that wiped out the dinosaurs and many other species in one of several so-called "times of great dying" that might be linked to meteorites.

"Instead of continuous progression, there have been very sudden and violent events that altered our biological and geological evolution," Roddy said. "This kind of planetary research is really important to understand what can go wrong (in climate change) and avoid it."

Although Meteor Crater has been a feature of the Earth for about 49,000 years, Roddy said it did not gain general recognition until the 1960s - after public interest in the space age had grown.

All astronauts in the Apollo lunar landing program between 1969 and 1972 trained at Meteor Crater so they could tell a meteorite crater from a volcanic crater, a distinction that eluded the foremost scientists of the late 1800s.

A Philadelphia lawyer, Daniel Moreau Barringer, believed that any crater with meteorite fragments lying all around it must be a meteorite crater. However, the foremost geologist of his time, G.K. Gilbert, insisted in 1880 that it was a volcanic steam crater, and that the meteorite fragments lying around the hole were purely coincidental.

"My father's reaction was, that is a hell of a coincidence," says J. Paul Barringer, 88, one of three surviving sons of the founder of the Barringer Crater Co., which has controlling interest in the crater and funds crater research around the world.

The elder Barringer took mining patents on the land, intending to mine the crater for what he hoped was $1 billion worth of iron and nickel.

"They are sitting in my safety deposit box, signed by President Teddy Roosevelt in 1903, when presidents had time to sign mining patents," says J. Paul Barringer, a retired U.S. foreign service official.

Scientists believe most of the Arizona meteorite evaporated on impact, but the elder Barringer spent much of his life and $600,000 futilely drilling for the celestial lode. About 30 tons of fragments were found and some of the largest are now on display in the world great museums, including Chicago's Field Museum of Natural History.

The elder Barringer was criticized by the scientific community for insisting it was a meteorite crater, although opinion was shifting in his direction when he died in 1929.

The Barringers have insisted on private ownership of the meteor crater, which was listed in 1968 by the Interior Department as one of the nation's 587 natural landmarks.

"We know how father suffered over this thing, both from scientific ridicule and the loss of much of his money," says J. Paul Barringer. "We wanted to keep it as a sort of memory to him and to have his name associated with the science now called meteoritics. He was the first man who demonstrated that large objects fell out of the solar system onto the surface of the Earth."

Now there are craters on Earth and the moon named for Barringer, the only person with that distinction.