Apollo 17 Experiment Finds an Atmosphere on our Moon

While it may not be much above that of the complete vacuum of space, an experiment left behind on the lunar surface by the Apollo 17 astronauts is now showing that the moon actually does have an atmosphere. What’s more, the atmosphere on the Moon is unlike that of the Earth or its closest neighbors in the solar system.

During the final mission to the moon, the crew of Apollo 17 deployed and left behind an instrument called the Lunar Atmospheric Composition Experiment (LACE). Now NASA scientists have been able to use the device, through telescopes here on Earth, to detect small amounts of a number of atoms and molecules including helium, argon, and possibly neon, ammonia, methane and carbon dioxide.

In a press release, NASA points out however that the moon’s atmosphere is incredibly small when compared with that here on the Earth. “At sea level on Earth, we breathe in an atmosphere where each cubic centimeter contains 10,000,000,000,000,000,000 molecules; by comparison the lunar atmosphere has less than 1,000,000 molecules in the same volume. That still sounds like a lot, but it is what we consider to be a very good vacuum on Earth.”

To make the discovery, the scientists on Earth used special telescopes that block light from the moon’s surface. They were then able to capture images of the, “glow from sodium and potassium atoms in the moon’s atmosphere as they are energized by the sun.” NASA points out that the research is currently incomplete and that they expect to find other gases in the composition of the newly discovered lunar atmosphere.

So where does the moon’s atmosphere come from? The researchers theorize that among the potential sources of lunar atmosphere are, “high energy photons and solar wind particles knocking atoms from the lunar surface, chemical reactions between the solar wind and lunar surface material, evaporation of surface material, material released from the impacts of comets and meteoroids, and out-gassing from the moon’s interior.”