The surface of the moon may be littered with fossils from ancient Earth, scientists say, and new research is shedding light on the astonishing way that they arrived there.
While it may seem like a surprising idea that fossils could travel between planetary bodies, experiments conducted by physicists at the University of Kent are proving that fossilized diatoms can survive the trip, according to Popular Science. Their findings suggest that meteorites are capable of transporting fossils between worlds, at least when impacts occur at certain speeds.
First image of the moon taken by a US spacecraft. #OTD 1964, Ranger 7 took this pic: http://t.co/GEuHAt1oTD #TBT pic.twitter.com/Nbm7QmHx9a
— NASA (@NASA) July 31, 2014
As io9 relates, the journey from the Earth to the Moon would be a hazardous one for fossilized microorganisms, involving two "shock events." The first would consist of an impact strong enough to throw high-speed ejecta containing fossils into the air, which would then escape into space. As they reach another planetary body, like the Moon, there would be another shock event as the fossil-laden meteorites impact the surface at speeds as high as 3 kilometers per second.
There's Now a Reason to Go Fossil Hunting on the Moon http://t.co/q9BtWBzgqX pic.twitter.com/bE0vRFEnzL — ExpandedPerspectives (@ExpandedP) July 30, 2014
Spurred on by the debate over Martian meteorite ALH84001 and whether it contains fossils of diatoms, which would be evidence that life once existed on Mars, the University of Kent team decided to test the ability of fossils to survive such a journey intact. By using powdered diatoms -- a type of microscopic algae with a hard silica shell -- frozen inside a nylon bullet, they simulated fossilization and impact speeds. When the bullets were fired into a sack of water at speeds ranging between 0.25 and 3.1 miles per second, researchers were able to determine that small fossils could possibly survive a meteorite impact, with a few caveats.
Is the Moon littered with fossils from Earth? http://t.co/d6mmhaImwQ pic.twitter.com/qegJToqqQr — Discovery Canada (@DiscoveryCanada) July 29, 2014
At impact speeds above 0.62 miles per second, none of the pseudo-fossilized diatoms survived impact. As the speed of impact increased, the surviving fragments became smaller. Meteoroids generally enter the Earth's atmosphere at speeds between 6.8 and 44.7 miles per second before they strike the surface, posing a serious stumbling block to the survival of such fossils. Still, despite their fragmentation, the diatom fossils could still be recognized as biological in origin.
Small pieces of the Moon occasionally reach Earth as meteorites! More meteorite fun facts: http://t.co/DMaaSESdZJ pic.twitter.com/sZNlxyq3rp — AMNH (@AMNH) July 28, 2014
It is well known that asteroids have struck the Earth's surface in the past, as The Inquisitr has reported. With that fact in mind, future lunar expeditions may very well find fossils from Earth's distant past scattered over the surface of the moon.
[Image via Motherboard]