Aliens from over 1,700 stars may have already noticed us, according to scientists.
A team of US scientists has reported that if aliens exist among a cluster of more than 1,700 neighboring star systems, they may have already identified our planet.
Scientists from Cornell University in New York and the American Natural History Museum have revealed almost 2,000 neighboring star systems that are close enough for aliens to observe our planet today (June 23). All of the star systems are within 326 light-years of our planet, which is close enough for our planet to pass within their field of vision as it transits the Sun. The astronomers discovered a total of 1,715 systems that may have seen our planet long before human civilisation arose 5,000 years ago.
In addition, 319 more systems are expected to be introduced over the following 5,000 years.
The star systems were revealed in a report published in Nature on June 23.
Exoplanets orbiting these stars, according to the study’s authors, are well positioned to see if life exists on Earth.
“From the perspective of the exoplanets, we are the aliens,” Lisa Kaltenegger, professor of astronomy and head of Cornell’s Carl Sagan Institute, stated.
If alien life exists among the stars, it may be looking for other types of life in the same manner that scientists on Earth do.
Searching for transiting worlds is one way that organizations like NASA are looking for habitable exoplanets.
When a planet passes between a star and its observer, this is known as a transit.
Scientists can then examine the chemical makeup of the planet’s atmosphere to see if any indicators of life are there.
“We wanted to know which stars have the best vantage point to see Earth because it blocks the Sun’s light,” Professor Kaltenegger explained.
“This vantage point is gained and lost because stars migrate in our dynamic cosmos.”
The transit approach is used by missions like NASA’s TESS, or Transiting Exoplanet Survey Satellite, to find hundreds of candidate exoplanets beyond our solar system.
Professor Kaltenegger and her colleagues used the European Space Agency’s (ESA) Gaia eDR3 collection to map neighboring star systems.
They were able to use the catalog to figure out which stars dip into and out of the Earth Transit Zone.
“Gaia has supplied us with an accurate map of the Milky Way galaxy, allowing us to gaze backwards and forwards in,” said Jackie Faherty, an astronomer and senior scientist at the museum.