Is it possible to own the earth?

Life on earth is detectable for extraterrestrials

In a few centuries, however, extraterrestrials could also see other signs of our technological capabilities. For example, in a new study in the Astrophysical Journal, astrophysicist Hector Socas-Navarro demonstrated that we could find intelligent life by looking for satellites orbiting other worlds. This means that aliens could find us the same way.

When a planet with numerous satellites passes in front of its home star, the satellite belt blocks some of the starlight before and after the planet itself begins or completes its transit. This metallic belt would stand out in comparison to natural planetary rings.

Currently, the Earth's satellite network is nowhere near dense enough to be discovered this way. But it's growing all the time. According to Socas-Navarro, if humanity continues to shoot satellites into Earth orbit at the current rate, they could be discovered by aliens in 200 years with telescopes that are state-of-the-art.

ALWAYS IN CHANGE

The earth is around 4.5 billion years old - during this period, life on our planet has changed dramatically. What if extraterrestrial astronomers looked our way a billion years ago?

In 2018, as part of a study that appeared in Science Advances, Olson and her colleagues simulated how the Earth's atmosphere had changed over time. Even three billion years ago, extraterrestrials could have inferred life from the methane and carbon dioxide in the Earth's early atmosphere. However, our modern atmosphere is only around 500 million years old.

"For more than a billion years, an extraterrestrial astronomer could have been sufficiently deceived to conclude that the earth was barren - despite the fact that marine life was thriving at the time," explains Olson.

Still, if the aliens were progressive and thorough enough, even a young Earth would have provided convincing evidence of life, says co-author of the study Joshua Krissansen-Totton of the University of Washington.

"The existence of life on Earth has been evident for the past four billion years to anyone who could build a large enough telescope," he wrote in an email. “If there was anything bad out there, it would have wiped out life on earth a long time ago. I think we will be safe if we invite them to visit and talk about the cosmos. "

If the aliens tick like us, the news that they are not alone in space would probably not be earth-shattering either. A study published in Frontiers in Psychology in February suggests that humanity would be fine with the discovery of extraterrestrial life.

"People will be able to adapt themselves to very important scientific discoveries without their world collapsing," said theologian Ted Peters in this context.

But just like us, potential aliens could be afraid of hostile aliens - in this case humans - who suddenly appear on their cosmic doorstep without notice.

"Of course," added the study author Michael Varnum of Arizona State University, "I would also predict that we would not be happy if an enemy armada appeared near Jupiter."

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