THAT MIGHT NOT BE SUCH A GOOD IDEA
Elon Musk Could Help Aliens Notice Humans, Study Says
Caroline Delbert 

POPMECH

4/4/2021

Earth could eventually be visible to aliens because of the signature left by Starlink satellites.

Scientists say this will take about 1,000 years.

This research could also help scientists tune our telescopes to better see aliens.

Elon Musk has a grand goal for SpaceX’s Starlink: use an eventual 40,000 satellites to blanket the entire planet in internet coverage, far surpassing any existing satellite internet service. But there may be more to the mission. In a new study, one scientist suggests Musk’s satellite network may also make Earth a major target of alien interest.

➡ You think space is bad***. So do we. Let’s nerd out over it together.

Starlink’s 40,000 satellites in orbit—1,000 of which astronomers have already criticized for obstructing the night sky—will be enough to register as a megastructure that will eventually appear on some faraway civilization’s radar, writes Zaza Osmanov, a professor of astrophysics at the Free University of Tbilisi in Georgia, in a new paper published to the preprint server arXiv.

Osmanov studied how the electrical signature of Starlink will show up via signals to large interferometers in distant alien civilizations. Since Earth’s advanced interferometers would be able to detect this activity from other planets, Osmanov writes, anyone else with the same technology could do the same back to us.

“We consider the possible observational characteristics of a planetary megastructure partially or completely covering an Earth-like planet located in the habitable zone,” Osmanov explains. That means finding the key inflection point at which the Starlink satellite network would become detectable to a faraway observer.

To assess what’s visible from where, Osmanov explored what it would mean to cover Earth with a large amount of literally anything. Is there enough graphene, for example, to blanket the atmosphere and become visible from deep space? It turns out there’s enough carbon available to us to do this many, many times over if we wanted—like an Everlasting Gobstopper of Earth-size graphene layers.

How much time will we need to launch and place that much material, now that we know we have it? Osmanov estimates this will take 1,000 years of launches at regular intervals. At that point, enough material would be in space for humans to become visible to aliens.

And what about Starlink? Musk doesn’t have plans to make a material blanket as part of his satellite network—this would block the sun, and not in the hip Bill Gates way. If people are mad about thousands of tiny satellites, imagine how a giant sky blanket would go over. But the radio signals thrown off by Starlink and other satellites mean the right instrument on a faraway planet could observe the satellite network’s energy and wave signature.

There’s even a third option, speaking of the Gates-funded geoengineering. If Earthlings decide to fill the stratosphere with aerosol particles as a way to reflect away warming solar radiation, it’s feasible to wonder if that level of reflection would be visible as some kind of iridescent shimmer. Will Earth light up like an iconic color-changing‘90s Ford Explorer?

For now, Earth is safely invisible to the faraway telescopes and instruments of any aliens scanning the skies with comparable technology to our own. Of course, that presumes that they’re not already watching us.