BOSTON (AP) — Anyone who can’t make it to the moon to gather a few lunar rocks now has the opportunity to buy one right here on Earth.

A 12-pound (5.5 kilogram) lunar meteorite discovered in Northwest Africa last year is up for auction by Boston-based RR Auction and could sell for $500,000 or more during online bidding that runs from Thursday until Oct. 18.

It is “one of the most important meteorites available for acquisition anywhere in the world today,” and one of the biggest pieces of the moon ever put up for sale, RR said.

The rock classified as NWA 11789, also known as “Buagaba,” was found last year in a remote area of Mauritania but probably plunged to Earth thousands of years ago.

The meteorite is actually composed of six fragments that fit together like a puzzle. The largest of those pieces weighs about 6 pounds.

Most lunar meteorites found are the size of a walnut or golf ball, said Geoff Notkin, star of television’s “Meteorite Men” and CEO of Aerolite Meteorites, which is selling the rock.

“As soon as we saw this, we knew it was extraordinarily unusual,” he said. “This is close to a once in a lifetime find.”

It is also one the few known lunar meteorites with what experts call “partial fusion crust,” caused by the tremendous heat that sears the rock as it descends through the atmosphere.

“It actually toasted on the outside,” Notkin said.