With the list of unexplored places on Earth growing smaller and smaller everyday, the odds of us finding new evidence pointing to our planet’s origins decreases. Surprisingly we could look to the stars to learn more. The moon is lifeless, and probably always will be, however this very deadness makes it extremely important in our search for the origin of Earth. It is possible that the moon’s surface holds an unprecedented fossil record of life on Earth or from our surrounding planets. The oldest evidence of life on Earth dates back to 3.5 billion years ago. There is a major possibility that we could find evidence of life on the Moon coming from Earth dating back much further than this. Because the Moon has no atmosphere and no plate tectonics, anything that lands there stays in pristine condition. I, without a doubt, believe that there is some form of Earth material showing signs of life on the Moon.
The last time we visited the Moon was 1972. Now we are all very focused on our next major objective, Mars, but are we skipping over a key to our past? We have only visited a minuscule fraction of the Moon and we have already dismissed it as lifeless and dead. There is so much potential for what we could find if we go back.
Through the research of Luis and Walter Alvarez in the 1980s it was discovered that small bits of Earth and astroids are sprinkled around the Earth. After asteroid impacts, pieces of rock had been flung into space and melted on re-entry into the atmosphere creating tektites. The bits and pieces of crater and asteroid spread all over the world is a testament to the violence of the event and evidence that most of the ejected crust took to space and even circled the globe before finally falling back to Earth. Could these chunks of rock travel to the moon though? A Journal, Icarus, in 2002 said it could and that although most rock travels back down to Earth, an appreciable amount breaks free and fell onto other bodies in our solar system. This was proven when the meteorite ALH 84001 was discovered and believed to contain fossils of bacterial life from Mars. Although the bacteria part was wrong, this discovery did point to the fact that planetary rocks could routinely travel vast distances across the solar system. This also breathed life into the concept of panspermia which is the idea that microbes can travel from planet to plant on rock blasted into space by an impact.
A man named John Armstrong teamed up with Llyd Wells and Guillermo Gonzalez to begin serious work of calculating whether a impact on the Earth could send enough amounts of material to the moon. They decided that in order for this idea to be accepted they would need to figure out how big the impact would need to be to propel crust beyond our planets gravitational pull and they would need to see if the frequency of these events is enough for appreciable quantities of material to end up on the moon. Through their research they found that the asteroid would actually only need to be about 100 meters in diameter and leave a crater a kilometer across, this is relatively small as asteroids come in the past. It seems the rate of these types of impacts is roughly once every 100,000 years recently, and far more frequently in the distant past. Armstrong and his team calculated that a single impact of a 100 meter asteroid would deposit about 120 kilograms of fairly pristine Earth rock on each 100 square kilometers of the moon surface. Even with a conservative estimate, there could be up to a few million tons of Earth rock on the Moon. The material is there and waiting to be found, all we need to do is look for it.Tags: Fossilshistorymoonnasaspace
Fossils on the Moon by Charlie is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.