by If all the world’s a stage, then ET has a front row seat.
Astronomers have identified 2,034 star-systems just a stone’s throw away from us in cosmic terms that could spot Earth by watching it cross the sun.
The scientists from Cornell University and the American Museum of Natural History say 1,715 star systems could have seen earth seen civilization arose around 5,000 years ago, with 319 systems added over the next 5,000 years.
If these systems host exoplanets which have given risen to intelligent life, the fact that they’ll all be within 326 light years of our planet means they could directly see or hear us.
“From the exoplanets’ point-of-view, we are the aliens,” said Lisa Kaltenegger, professor of astronomy and director of Cornell’s Carl Sagan Institute, in the College of Arts and Sciences.
“We wanted to know which stars have the right vantage point to see Earth, as it blocks the Sun’s light,” she said.
“And because stars move in our dynamic cosmos, this vantage point is gained and lost.”
Lisa, along with astrophysicist Jackie Faherty, from the American Museum of Natural History, are co-authors of “Past, Present and Future Stars That Can See Earth as a Transiting Exoplanet.”
They reached their conclusions using the European Space Agency’s Gaia eDR3 catalogue to determine which stars enter and exit the Earth Transit Zone and for how long.
“Gaia has provided us with a precise map of the Milky Way galaxy,” Faherty said, “allowing us to look backward and forward in time, and to see where stars had been located and where they are going.
“Our solar neighbourhood is a dynamic place where stars enter and exit that perfect vantage point to see Earth transit the Sun at a rapid pace,” Faherty said.
Picture: OpenSpace/American Museum of Natural History
