It was after the discovery of interstellar asteroid Oumuamua that Professor Avi Loeb from Harvard University suggested it could most probably be an alien probe. Now, Avi Loeb along with another Harvard researcher Amir Siraj, in a new study paper has suggested the possibility of alien life escaping earth several times in the past.
How does alien life escape earth?
In their new study paper, the researchers proposed a possible scenario that happened in the past when the solar system was more crowded. During this time, a giant comet graced the outer reach of the earth's atmosphere. In its course, the comet was moving several tens of miles above the earth's surface, and this distance was too high for them to burn up into debris.
In this course, some of the bugs living in the atmosphere survived the collision with the iceball, and they finally ended up living in the comet's porous surface. The comet continued its journey and ended up in other solar systems where they deposited seeds of life.
Scientists have named this process "interstellar panspermia" which means seeding of distant star systems with exported life from other systems.
However, skeptics believe that the chances of the microbes surviving in the comet's surface are unlikely. Even though certain bacteria can survive harsh conditions for decades, it is still unclear whether the unicellular creatures can survive thousands or millions of years that are necessary to reach another system.
Alien life to be discovered on a space rock
Ian Whittaker, a lecturer in physics at Nottingham Trent University and Gareth Dorian, postdoctoral research fellow in Space Science at the University of Birmingham, in their article published in The Conversation suggested that alien life could soon be discovered on asteroids.
The researchers also noted that studying asteroid Ryugu is very much crucial in discovering alien life traveling in space rocks. In the article, the researchers also suggested that analysis that will be conducted on Ryugu will help to understand more about panspermia theory.