If the moon is truly a chunk of the Earth broken off during the planet's formation, then it stands to reason that the lunar satellite once had a hot, geologically active surface.
According to Space.com, authors of a study published in the journal Nature Geoscience suggest the moon once experienced fiery explosions from geysers on its surface. The researchers classified the geysers as fountains, as they were not the size of an Earthly volcano, but they spewed lava nonetheless.
"The question for many years was what gas produced these sorts of eruptions on the Moon," study co-author Alberto Saal, an associate professor of earth, environmental, and planetary sciences at Brown University, said in a press release. "The gas is gone, so it hasn't been easy to figure out."
The researchers pointed to carbon as the likely suspect.
"The carbon is the one that is producing the large spectacle," Saal told Space.com. "With a little bit of water, with a little bit of sulfur - but the main driver is carbon.
"All these volatile elements... are in concentrations that are very similar to the lava that formed the ocean floor of the Earth."
Saal was part of a research team that identified traces of water that once existed on the moon, another compositional link connecting it to the Earth. That study, published in 2008, was the first of its kind.
"Most of the carbon would have degassed deep under the surface," Saal said in the release. "Other volatiles like hydrogen degassed later, when the magma was much closer to the surface and after the lava began breaking up into small globules. That suggests carbon was driving the process in its early stages."
