Traces of Mars' unique atmosphere are trapped within the rock dubbed the Tissint meteorite, the University of Alberta reported Thursday.
"Our team matched traces of gases found inside the Tissint meteorite with samples of Mars' atmosphere collected in 1976 by Viking, NASA's Mars lander mission," researcher Chris Herd said.
The meteorite was a fairly typical volcanic rock on the surface of Mars until it was launched off the planet by the impact of an asteroid 600 million years ago, he said.
"At the instant of that impact with Mars, a shock wave shot through the rock," Herd said. "Cracks and fissures within the rock were sealed instantly by the heat, trapping components of Mars' atmosphere inside, and forming black, glassy spots."
For a period estimated at between 700,000 and one million years the rock floated through outer space, until July 2011 when it streaked through Earth's atmosphere to land in Morocco.
This meteorite is important because it was picked up just a few months after landing and was not subjected to weathering or contamination on Earth.
While on Mars the rock was weathered by water, which means water was present on the surface of Mars within the past few hundred million years.
But this meteorite sample does not carry any evidence the martian water supported any life forms, Herd said.
"Because the Martian rock was subjected to such intense heat, any water-borne microbial life forms that may have existed deep within cracks of the rock would have been destroyed," he said.