Planets: The possibility of the existence of alien life may have gained a new focus in the scientific world. If intelligent beings are proven to exist in the cosmos, astronomers have listed some nearby star systems that could visualize the Earth through its movement around the Sun and its radio signal emissions.
In new research published in the journal Nature, scientists have estimated that 29 celestial bodies from the past, present and future must be in a privileged position to be able to observe terrestrial planetary transit and intercept human transmissions.
“One way to find planets is if they block some of their host star’s light. We asked, ‘Who would the aliens be if someone else were looking?’ Carl Sagan at Cornell University in New York.
In all, 2,034 star systems were identified in 100 parsecs (326 light years away) that could have “discovered” the Earth in a period of 5,000 years; of those, 46 would be close enough to detect a sign of human existence. As a method, the team analyzed data from the European Space Agency (ESA), through the Gaia mapping mission of the galaxy.
One save for everyone
The first example is the red dwarf Ross 128, a star in the constellation Virgo about 11 light-years away from the Solar System. It has an orbiting planet that could harbor life and have been able to visualize Earth for over 2,000 years. However, it lost that ability 900 years ago.
Already in the star of Teegarden, located in the constellation Aries about 12 light-years away, a hypothetical life could only see our home in 29 years. Scientists have also pointed out that planets from host star Trappist-1, 45 light-years away, should only witness our presence 1,642 years into the future.
For Beth Biller, a professor at the Institute of Astronomy at the University of Edinburgh — but not involved in the research — the work could help scientists in other aspects in their search for alien life. “For me, the low number of stars in 100 parsecs that could have seen an Earth in transit was impressive,” she told The Guardian.