The asteroid shower theory may hold key to understanding the abundant presence of phosphorus in human constituency, as well as on Earth in general.
- Last Updated: July 22, 2020, 11:13 AM IST
It’s bad enough that we keep reporting about asteroids that are potentially hazardous for life on Earth. However, about 800 million years ago, the universe, our solar system and our planet were hardly the way they all are today. It is some time around then, scientists have stated in a new study, that Earth may have been hit by a massive asteroid shower – one that sent Earth into its deepest ice age, covering the entire world with ice during the Cryogenian period 720 million years ago.
Scientists believe that the asteroid shower may have come from the same cosmic event that led to the creation of the Eulalia family of asteroids, which in turn is believed to have given birth to Bennu – one of Earth’s closest asteroids, where NASA’s probe OSIRIS-REx is presently busy at. The study, undertaken by a group of Japanese scientists headed by cosmochemist Kentaro Terada of Osaka University, has been published online in the Nature Communications journal.
To conduct this study, the scientists studied 59 lunar craters from instruments onboard Japanese lunar orbiter Kaguya, and undertook radioisotope dating of ejected rocks from the moon’s crater impact sites to gauge the possible age of a major asteroid impact event in Earth (and the moon)’s history. Taking into assumption the apparent asteroid shower’s trajectory, the scientists reported that a staggering 50 TRILLION metric tonnes of meteoroids may have rained down to Earth, thereby creating reaction debris so dense that it trapped the Earth’s entire atmosphere, and hence caused a drastic cooling effect on the planet – dragging the planet into the deepest ice age ever to have happened on Earth.
Alongside the sheer volume of this projected impact, Terada mentioned in his study that the asteroid shower may also have caused a pivotal point in the evolution of life forms as we know today. According to him, the shower released 100 billion tonnes of phosphorus across Earth. This may have had a long-lasting effect on the evolution of life forms, since phosphorus is particularly abundant naturally on Earth, and also makes for a key element of human cell membranes and DNA.
Terada has stated that he now looks forward to asteroid samples collected from Bennu or nearby fellow asteroid Ryugu, and believes that it is this sample that will hold a key answer to his asteroid impact theory. Until then, his potentially impactful theory will hope to uncover more proofs of such a massive asteroid impact on Earth, although natural geological activity is believed to have erased any possible evidence of such activities that may have occurred more than 600 million years ago.