This is how foreigners can seek human life

In search for extraterrestrial life, we are usually us doing du spying. But Lisa Kaltenegger, an astronomer at Cornell University, wanted to know who might be looking there gu. “Who would we foreigners be for?” he asks.

So Kaltenegger enlisted the help of astrophysicist Jackie Faherty, who works at the Hayden Planetarium in New York City, part of the American Museum of Natural History. Together, the neighbors (past, present, or future) took on the task of identifying stars that could take on alien worlds that could be perceived as an exoplanet passing through the Earth. This means that their planet would have a suitable vantage point to immerse themselves slightly in the light of our sun when it crosses or passes in front of the Earth. This is the most successful method Earthlings use to find planets beyond our solar system, orbiting their host stars, creating small clips in the light we can see with astronomical instruments.

In June, Kaltenegger and Faherty reported their results Nature with an extensive inventory of stars that have had or will have the right orientation to know our planet. More than 2,000 stars were identified, using a time span from 5,000 years ago, when Earth civilizations first began to bloom, until 5,000 years into the future. Not only that examination provide a resource for exoplanets by specifying which stars to focus on; it also provides a unique — and arguably disturbing — view of the rest of the universe. “I felt a little spied on,” says Faherty, remembering the strange sensation of overexposure. “Do I want to be on a planet that can be found?”

“It’s a beautiful piece of scientific poetry to think about how all these objects move through space in this elaborate ballet,” says Bruce Macintosh, an astronomer at Stanford University who was not involved in the work. Being the first study of its kind to take into account the changing star gazettes that have changed over time, it is based on previous research that used only current positions in the cosmos. “Now we can build films that look like what the universe will look like in the future 5,000 years from now, depicting all the stars flashing as the planets obstruct the path,” he says.

The new result was made possible by the latest release from the European Space Agency’s Gaia mission, an orbiting observatory with the ambitious goal of creating a three-dimensional map of the positions and velocities of a billion stars. Faherty uses it along with planetary software to watch the movements of the stars, he and Kaltenegger have found 2,034 stars in the Earth’s passage field. For almost all of them, alien creatures living on the planets that surround these stars, with age technology, would be able to detect the presence of the Earth for at least a thousand years. “On the cosmic time scale, that’s a radar,” Kaltenegger says.

He says it gives astronomers a lot of time in human life to develop the tools they need to look at other worlds. Kaltenegger and Faherty hope that astronomers will use the catalog to find new planets, especially around stars that are not very well known or well studied. From there, big missions like NASA future James Webb space telescope, launched by the end of the year, can be used to study the planet’s atmosphere and look for signs of life. “This is a treasure trove for planets that want to find it,” says Kaltenegger. “I’m waiting for what people find.”