Thirty-five green rocks found in Morocco last year may actually be the first known meteorite samples from Mercury the world has ever seen.
The news comes from meteorite scientist from the University of Washington Anthony Irving who presented his study at the 44th annual Lunar and Planetary Science Conference in The Woodlands, Texas.
Other much more common meteorite sources, including Mars and the asteroid Vesta, were ruled out by analyzing the rock's chemical makeup, which is different than anything scientists have encountered in the form of space debris, Irving told Space.com.
Called NWA 7325, Irving and his team estimate the meteorite is 4.56 billion years old and if it's not from Mercury, then it's from a space body similar to it.
Evidence that the rock is a visitor from the solar system's innermost planet lies in its magnetic qualities that resemble those of Mercury's, according to data retrieved by NASA's Messenger, as well as the amount of iron found in both.
Irving believes the meteorite was formed in flowing magma, and in fact was a kind of "scum" that rose to the top.
To this day, Mercury remains one of the least understood of all the planets, despite its relative proximity to Earth. Sun-scorched and only slightly larger than the Earth's moon, it revolves around the Sun every 88 days. Temperatures vary drastically between morning and night, the latter being so cold that scientists believe there may be ice within the craters in the planet's permanently shadowed regions.
The spacecraft Messenger has been busy uncovering information about Mercury, including photographing parts of its surface that have never before been seen by human eyes, since it launched in 2004. It completed its first extended mission this month though its team has put in a request to continue research for the next two years.