Photo by: ESA/NASA/Hubble

ESA/NASA/Hubble

Are Aliens Calling Us From Proxima Centauri?

The internet and news media alike are abuzz with news about a radio buzz coming from Proxima Centauri, the nearest neighbor star to our sun a mere four and a quarter light-years away. That star happens to host a planet, called Proxima b (because we don’t have a cooler name for it yet), that sits in the habitable zone of its parent star. That means that the planet can potentially host liquid water, and where there’s liquid water there’s a chance for life.

February 11, 2021

Mysterious radio signal coming from a potentially-habitable star system? It’s almost too good to be true. And it is.

I’ll just go ahead and say it right now and get it over with: it’s not aliens. It’s never aliens. We’ve been listening for calls from E.T. for well over half a century now, and every single mysterious radio signal has turned out to be…less than mysterious.

But could this be it? Could this be the one to buck the trend, and be our first communication from an alien civilization?

First, let’s be cautious about the source. I mean about the news, not the radio signal. The story first appeared in The Guardian and Scientific American, both reputable publications. But the story was based on a leak from someone in the Breakthrough Listen team, the collaboration funded by billionaire Yuri Milner to piggyback on radio telescopes around the world to listen for aliens calling.

Artist’s impression of the exoplanet Proxima Centauri b.

Photo by: ESO/M. Kornmesser/NASA

ESO/M. Kornmesser/NASA

Artist’s impression of the exoplanet Proxima Centauri b.

There is no paper. There are no data. There is no peer-review. There is no discussion about what they’ve found, the work they’ve done, and assumptions they’ve made, or the analysis performed. All we know is that they caught a bright radio signal coming from the vague direction of Proxima Centauri a few times in the summer of 2019 – note that they didn’t see the signal every time they looked, only sometimes.

The signal is at a frequency of 982.002 megahertz, which is generally free from human-made interference, hence it piqued the interest of the researchers. But while eager E.T. explorers want to point to Proxima b as the source, apparently the signal changed frequency in a way incompatible with the way that planet orbits its star.

And that’s it. That’s literally all we know.

Artist's impression of the planet orbiting Proxima Centauri

Artist's impression of the planet orbiting Proxima Centauri

This artist’s impression shows a view of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The double star Alpha Centauri AB also appears in the image to the upper-right of Proxima itself. Proxima b is a little more massive than the Earth and orbits in the habitable zone around Proxima Centauri, where the temperature is suitable for liquid water to exist on its surface.

Photo by: ESO/M. Kornmesser/NASA

ESO/M. Kornmesser/NASA

This artist’s impression shows a view of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The double star Alpha Centauri AB also appears in the image to the upper-right of Proxima itself. Proxima b is a little more massive than the Earth and orbits in the habitable zone around Proxima Centauri, where the temperature is suitable for liquid water to exist on its surface.

Here’s the thing. Even if we’re never, ever able to come up with an explanation for this signal – even if we rule out every single known human and astrophysical source – it still doesn’t mean that this is a sign of alien intelligence. Failing to come up with an explanation does not give you permission to identify a signal as produced by aliens.

That’s because, being intelligent creatures, aliens are in theory able to generate any kind of signal you could possibly want. Anything you find mysterious in the night sky could be explained by aliens, and so that makes it useless as a scientific hypothesis to explain an unknown signal. To properly hunt of aliens, you have to predict what kind of evidence you expect to find, then go looking for that.

Proxima Centauri b is a super Earth exoplanet that orbits a M-type star. Its mass is 1.27 Earths, it takes 11.2 days to complete one orbit of its star, and is 0.0485 AU from its star. Its discovery was announced in 2016.

Photo by: NASA/JPL-Caltech/T. Pyle

NASA/JPL-Caltech/T. Pyle

Proxima Centauri b is a super Earth exoplanet that orbits a M-type star. Its mass is 1.27 Earths, it takes 11.2 days to complete one orbit of its star, and is 0.0485 AU from its star. Its discovery was announced in 2016.

And that’s why I’m entirely confident in saying that even if we never explain the origins of this signal (which is itself highly unlikely), it’s still not aliens.

Paul M. Sutter

Paul M. Sutter is an astrophysicist at Stony Brook University and the Flatiron Institute, host of Ask a Spaceman and Space Radio, and author of How to Die in Space.

Next Up

How Common are Water Worlds in the Galaxy?

If Kevin Costner wanted to make a sequel, he’s got plenty of opportunities. Water is by far the most common molecule in the universe. It’s made of two parts hydrogen and one part oxygen. Hydrogen is element number 1 (both on the period table and in abundance), and has been hanging around since the first 15 minutes of the Big Bang. Oxygen is forged in the hearts of sun-like stars, and spreads around when those stars die and turn themselves inside out. And since sun-like stars are also very popular, oxygen gets quite a boost.

China and Russia are Building Lunar Space Station Together

Recently announced, development for an international lunar space station is underway as China and Russia are joining together to build research facilities in orbit and possibly on the moon.

NASA and SpaceX are Going on a Date, and We're All Invited

Save the date--On May 27th, if everything goes as planned, a rocket will launch from Kennedy Space Center in Cape Canaveral, Florida. Watch SPACE LAUNCH LIVE: AMERICA RETURNS TO SPACE on Discovery and Science Channel starting at 2P ET.

Waste In Space: NASA's Lunar Loo Challenge

Would YOU like to design one of the next toilets used in space?

NASA Astronauts Take on Two Spacewalks at the International Space Station

Updated July 1, 2020 Six Days. Two spacewalks. Both Successful.

The Last Supermoon of the Year and How to See It

The Super Flower Moon of May is this year's last supermoon, when the Moon appears slightly larger and brighter in the sky because it is somewhat closer to Earth. Here's everything you need to know and how to watch it from home.

Something Funky is Happening to the Earth’s Magnetic Field

Recently a weak spot in the Earth's magnetic field over the southern Atlantic Ocean has been getting weaker, which could signal the beginnings of a global magnetic reversal event. Or not. It’s complicated.

NASA and SpaceX to Launch a Crewed Mission to ISS in May 2020

For the first time since its conception 18 years ago, SpaceX, along with NASA, will launch a crewed mission to space.

NASA HQ to be Named in Honor of Mary W. Jackson

NASA announced Wednesday, June 24th that NASA's Washington, D.C. headquarters will now be named for Mary W. Jackson, the first black, female engineer at NASA.

Large Rocket Debris Impacts Earth Off African Coast

The fourth largest piece of space debris ever re-entered the earth's atmosphere yesterday and made a splash just off the coast of Africa. Narrowly missing some major landmarks in its path, this piece of a rocket could have caused some major damage.
Related To: