Sometime between the last glacier age 18,000 years ago and the beginning of recorded history, a huge meteor may have landed on Chappaquiddick. And Mike L. Jackson, 40, and his older brother, Dennis L. Jackson, 42, of Edgartown, believe they have evidence.

The two men believe they have recovered pieces of the fallen meteor from the shore of Cape Pogue Pond. They have shared the news of their collection with David A. Nellis, 74, a retired University of Massachusetts college professor of geology, mineralogy and petrology who lives in Scituate.

And Mr. Nellis believes they may be correct.

Meanwhile, their collaboration has sparked an even bigger idea.

Mr. Nellis and the Jackson brothers wonder whether Cape Pogue Pond itself could have been created by a falling meteor.

It is true that the pond has features unlike any other Island pond.

Some Island ponds are what are known as kettle holes, formed by huge blocks of ice melting away during the glacial age. Seth’s, Ice House and Harlock’s Pond are all examples of kettle hole ponds.

“Most circular ponds are kettle holes,” Mr. Nellis explained. He added: “Kettle holes are deep ponds. Cape Pogue Pond is very shallow.”

Cape Pogue Pond is also different from other Island coastal ponds and embayments. Unlike the Great Ponds on the south shore of the Island, or Sengekontacket, Lagoon Pond or Lake Tashmoo, Cape Pogue Pond is not an estuary. A study of the pond done by a Woods Hole marine scientist in the late 1990s found that the pond is a rare ocean lagoon, flooded with undiluted saltwater that flows in and out of the naturally formed gut, an interior that has remained unchanged since it was first charted in 1776.

But that brings the story back to the subject of stones.

The Jackson brothers spend a lot of time walking the Island beaches. Mike, who is a skilled pipe fitter, loves to collect stones and other things from the shore. He has accumulated a fine collection of arrowheads. And he believes the nearly black stones that he has collected from the edge of Cape Pogue Pond are not of this world.

The stones could be slag from a foundry, road metal or ship ballast. Or they could be something else.

The stones have creases on them, which suggest that they were quickly melted and hardened. In the language of meteors this is called fusion crust, which means at some time the surface of the stone was exposed to intense heat, softened for a short time and then cooled.

The Jackson brothers have amassed a large number of these black stones. With the permission of the property owner on the pond, they dug and collected enough pieces, that when put together they resemble a third of a three-foot sphere.

Mr. Nellis, whose expertise is not in meteors but in other types of stones, has traveled to Brazil, Venezuela, Canada and western United States for his work. For 30 years he taught geology, mineralogy and petrology at the University of Massachusetts in Boston.

As a summer visitor to the Island, Mr. Nellis said he took a special interest in the Jackson discovery and began to gather whatever new and old information he could to help. He gathered enough material to write a 10-page scientific paper titled Martha’s Vineyard Meteorite.

In the paper, Mr. Nellis explains why he believes the stones found at Cape Pogue Pond may have come from outer space: “There are nine physical properties analyzed and recorded by this author after examining approximately 30 fragments from this find . . . The single most important physical feature is the Widmanstatten texture. Scientists who are familiar with meteorite science consider Widmanstatten texture to be definitive for declaring an object to be meteorite in origin.”

The stones also are magnetic.

Mr. Jackson displayed one of the matching stones from his collection. The Widmanstatten texture on the side of the stone resembles a cobweb with its delicate pattern. The fusion crust is shiny and textured.

Meteors are stones from outer space that enter the earth’s atmosphere at fantastic speeds of up to 18,000 miles per hour. Most burn up before they make it to the ground. The larger stones fall to earth, sometimes creating a crater, sometimes lodging deep in the soil.

Meteors are collectible and this creates a conflict for the Jackson brothers as they try to draw attention to their find. They may be able to sell what they have collected, but they also want to protect the site from other collectors in the name of further scientific research. One brother wears a necklace with a stone cut from one of their finds. The other brother would like to make sculptures from the stones.

Last March, Mr. Nellis attended the annual meeting of the Northeastern Section, Geological Society of America, in Portland, Me., where he set up a display and shared his paper. Though not a member of the society, Mr. Nellis exhibited his work hoping to spur interest. He said he left the meeting disappointed.

He has contacted other academic organizations but has received only a lukewarm response at best. He is still waiting to hear back from the department of earth and environmental science at the University of Rochester.

“I would like these people to sit down and discuss with us what we’ve got,” Mr. Nellis said.

Last month, samples of moon rock collected by NASA astronauts almost 40 years ago made a tour across the Vineyard’s libraries. The tiny samples of moon rock attracted hundreds of curious and interested visitors to the libraries.

The Jackson brothers said they were inspired by the program and feel the meteorites they believed they have collected are also worthy of interest.

One of the Island’s most valued coastal ponds, Cape Pogue Pond is among other things known as a rich repository for bay scallops. Mike Jackson said his stepmother has memories of scalloping in Cape Pogue years ago and pulling up odd-looking stones in her scallop drags.

“We’ve got quite a lot of evidence. I’d love to see a debate take place where people could talk about what we’ve got,” he said.