If Apollo 17 astronauts could have taken a time machine into the future after taking off from the Moon, they would have seen that the pristine samples they collected are being studied with technology that no one even imagined in 1972.
NASA scientists at the space agency’s Goddard Space Flight Center got the best holiday gift ever when they opened 50-year-old vacuum-sealed tubes of moon soil that have remained untouched for decades. Astronauts on that mission obviously had the foresight to save lunar regolith so that someday, upgraded technology could reveal more about the birth of the universe. There are probably amino acids trapped in the gray soil that might tell us something about the emergence of life on Earth. That someday which Apollo-era scientists imagined is finally here.
“We don’t have any rocks on Earth that are older than about 4 billion years old, so we don’t know exactly how much volcanic activity there was or how heavily Earth was bombarded by asteroids” said planetary scientist Barbara Cohen, who heads Goddard’s Mid-Atlantic Noble Gas Research Laboratory, or MNGRL (pronounced “Moongirl” as a shoutout to its predominantly female scientists). “Since the Earth and the Moon formed together, we can use our findings from the Moon to infer what happened on the early Earth.”
About those amino acids. Many scientists believe that the life on Earth was the result of abiogenesis, meaning that those microbes swimming around the primordial soup that was our new and turbulent planet came into being after amino acids (the building blocks of DNA) somehow arranged themselves into certain structures. If any proof of that exists, it isn’t on this planet. The moon, especially regions that didn't get drowned in ancient lunar lava flows, could offer us a window into some of the answers we seek from billions of years ago. Asteroids that formed all those impact craters on the lunar surface could have also left behind evidence.
Other elements (literally) of what happened when the Earth and Moon were still young fireballs are noble gases. Because noble gases don’t react with much—they were once thought to be completely unreactive but have been found to form some compounds with xenon, radon and krypton—they are ideal for studying lunar radiation. The researchers at MNGRL can use these gases to figure out how long rocks and meteorite shards were exposed to various types of radiation. Which noble gases are present in the samples and how much of them is left could give us an unprecedented image of the Moon’s geologic phases.
How these gases originated could also tell us about what lunar space weather was like before dinosaurs were even a twinkle in Earth’s proverbial eye. MNGRL has the instruments to separate noble gases from rock and examine their isotopes to see if solar winds, cosmic rays or some other phenomena swept them through space until they finally settled on the Moon.
“We will use our findings to paint a picture of what kind of space environment affected [the Apollo 17 landing site] over hundreds of millions of years. This will provide important geologic context to scientists who analyze rocks from that site, especially our colleagues who are studying whether the buildings blocks of life formed on Earth or were delivered here from space,” MNGRL scientists Natalie Curran said.
Along with all the potential discoveries hiding in the specimens, the Apollo samples could inform scientists how to store future samples so they stay uncontaminated for extended periods of time. Who knows what Artemis astronauts could unearth.