Radio telescopes and the Milky Way

Illustration of a radio telescope satellite pointed at the stars in space. (© zhengzaishanchu - stock.adobe.com)

Some 540 million years ago, diverse life forms suddenly began to emerge from the muddy ocean floors of planet Earth. This period is known as the Cambrian Explosion, and these aquatic critters are our ancient ancestors.

All complex life on Earth evolved from these underwater creatures. Scientists believe all it took was an ever-so-slight increase in ocean oxygen levels above a certain threshold.

We may now be in the midst of a Cambrian Explosion for artificial intelligence (AI). In the past few years, a burst of incredibly capable AI programs like Midjourney, DALL-E 2 and ChatGPT have showcased the rapid progress we’ve made in machine learning.

AI is now used in virtually all areas of science to help researchers with routine classification tasks. It’s also helping our team of radio astronomers broaden the search for extraterrestrial life, and results so far have been promising.

Discovering alien signals with AI

As scientists searching for evidence of intelligent life beyond Earth, we have built an AI system that beats classical algorithms in signal detection tasks. Our AI was trained to search through data from radio telescopes for signals that couldn’t be generated by natural astrophysical processes.

When we fed our AI a previously studied dataset, it discovered eight signals of interest the classic algorithm missed. To be clear, these signals are probably not from extraterrestrial intelligence, and are more likely rare cases of radio interference.

Nonetheless, our findings – published in Nature Astronomy – highlight how AI techniques are sure to play a continued role in the search for extraterrestrial intelligence.

An AI-generated image signifying an AI entity searching for extraterrestrial life in space.
AI-based systems are being increasingly used to classify signals found in massive amounts of radio data, helping speed-up the search for alien life. (Generated by DALL-E 2, Author provided)

Not so intelligent

AI algorithms do not “understand” or “think”. They do excel at pattern recognition, and have proven exceedingly useful for tasks such as classification – but they don’t have the ability to problem solve. They only do the specific tasks they were trained to do.

So although the idea of an AI detecting extraterrestrial intelligence sounds like the plot of an exciting science fiction novel, both terms are flawed: AI programs are not intelligent, and searches for extraterrestrial intelligence can’t find direct evidence of intelligence.

Instead, radio astronomers look for radio “technosignatures”. These hypothesised signals would indicate the presence of technology and, by proxy, the existence of a society with the capability to harness technology for communication.

For our research, we created an algorithm that uses AI methods to classify signals as being either radio interference, or a genuine technosignature candidate. And our algorithm is performing better than we’d hoped.

What our AI algorithm does

Technosignature searches have been likened to looking for a needle in a cosmic haystack. Radio telescopes produce huge volumes of data, and in it are huge amounts of interference from sources such as phones, WiFi and satellites.

Search algorithms need to be able to sift out real technosignatures from “false positives”, and do so quickly. Our AI classifier delivers on these requirements.

It was devised by Peter Ma, a University of Toronto student and the lead author on our paper. To create a set of training data, Peter inserted simulated signals into real data, and then used this dataset to train an AI algorithm called an autoencoder. As the autoencoder processed the data, it “learned” to identify salient features in the data.

In a second step, these features were fed to an algorithm called a random forest classifier. This classifier creates decision trees to decide if a signal is noteworthy, or just radio interference – essentially separating the technosignature “needles” from the haystack.

After training our AI algorithm, we fed it more than 150 terabytes of data (480 observing hours) from the Green Bank Telescope in West Virginia. It identified 20,515 signals of interest, which we then had to manually inspect. Of these, eight signals had the characteristics of technosignatures, and couldn’t be attributed to radio interference.

Eight signals, no re-detections

To try and verify these signals, we went back to the telescope to re-observe all eight signals of interest. Unfortunately, we were not able to re-detect any of them in our follow-up observations.

We’ve been in similar situations before. In 2020 we detected a signal that turned out to be pernicious radio interference. While we will monitor these eight new candidates, the most likely explanation is they were unusual manifestations of radio interference: not aliens.

AI detects 8 new signals from the cosmos.
Midjourney (Author Provided)

Sadly the issue of radio interference isn’t going anywhere. But we will be better equipped to deal with it as new technologies emerge.

Narrowing the search

Our team recently deployed a powerful signal processor on the MeerKAT telescope in South Africa. MeerKAT uses a technique called interferometry to combine its 64 dishes to act as a single telescope. This technique is better able to pinpoint where in the sky a signal comes from, which will drastically reduce false positives from radio interference.

If astronomers do manage to detect a technosignature that can’t be explained away as interference, it would strongly suggest humans aren’t the sole creators of technology within the Galaxy. This would be one of the most profound discoveries imaginable.

At the same time, if we detect nothing, that doesn’t necessarily mean we’re the only technologically-capable “intelligent” species around. A non-detection could also mean we haven’t looked for the right type of signals, or our telescopes aren’t yet sensitive enough to detect faint transmissions from distant exoplanets.

We may need to cross a sensitivity threshold before a Cambrian Explosion of discoveries can be made. Alternatively, if we really are alone, we should reflect on the unique beauty and fragility of life here on Earth.The Conversation

Article by Danny C Price, Senior Research Fellow at Curtin University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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22 Comments

  1. Duane says:

    Wait. Since when did ” ‘ Diverse life forms’ suddenly emerge from the muddy ocean floors of planet earth” ? I didn’t know that this was biochemically solved.

    1. RocyD says:

      Duane, it’s the same religion as the climate alarmists- just a different pattern of cloth. Don’t question it, just believe it.

    2. Steve Austin says:

      I’m sorry that this doesn’t line up with your belief in a bronze-age book with a 6,000 year old earth where Adam and Eve rode their matching pet T. Rex’s and dealt with talking snakes.

      1. Whisperin Pints says:

        I’m sorry his comment doesn’t line up with your narrow view of the world, little fella. No, I’m not. Go play in traffic, kid.

      2. AlphaCrusis says:

        Your problem Steve is that your so called bronze age book wasn’t produced during the bronze age. It was collated over 1600 years (from the time of Moses) by 40 different authors.
        Its obvious that you evolutionists can’t get over the fact that in 1993 soft tissue was found by Dr. Mary Schweitzer in a T Rex fossil that included blood cells, blood vessels , collagen and still elastic soft tissue and since then over 30 other paleontologists have also found soft tissue in Tricertops, Duckbilled and other dinosaurs, so yeah, dinosaurs were around at the time of Adam ( Read Job 40: 15 – 24) but I doubt that they were riding them. Your millions of years like Darwinian evolution are dead in the water.
        As far as talking snakes are concerned you obviously don’t believe in miracles either.

      3. Peter says:

        Yes, and the greatest coincidence is that there was Abram and Sarah and at the same time there was Brahma and Sarasvati in India…

        Now that is something to ponder about.. Why al most exactly the same names of ancient gods and elders in different cultures?

    3. Nabi Rasch says:

      Take a bit of primordial mud, add a few tablespoons of calcium and salt and–presto!

  2. Kenneth Weigel says:

    This tends to confirm what I have long suspected. We are ALONE in the universe. Think about what that means!

    1. Nabi Rasch says:

      Huh?!

    2. Fred says:

      That’s impossible to process because we don’t know how big the universe actually means.

    3. Toll Seven says:

      Being alone in the galaxy is equally terrifying as the other possibility.

  3. LABillyboy says:

    So these radio signals, travelling at the speed of light may be 50 to 60 million years old when they get to us… the closest stars are 5 years in the past. Even in our own Milky Way, stars can be 890,000 years away… This all seems to be a waste of money and time. If there are ET’s and they somehow figure out how to beat space/time and covering light years of travel to get here… We’ll know it. There are over a billion smart phones out there with high resolution cameras. If there is a UFO, someone will get a crystal clear video or photo… that has never happened. All we have are grainy shots you can’t make out or just a bunch of lights moving around in the night… no proof.

    1. Fred says:

      So as long as they meet your requirement of what *Proof* is? It’s amazing how you cleared and sorted all the proposed evidence given thus far. You should be in charge.

  4. Martin B Napier says:

    The first radio waves from earth are only 120 years old…

  5. T.C. says:

    Lies, presumptions and misunderstandings.

    The earth is less than 6000 years old and we are about to enter the great tribulation as prophesied. It’s long past time to get real and stop feeding satanic delusions and propaganda for the unfolding great deception and turn to CHRIST ALMIGHTY with all our hearts. Our eternal souls are at stake and the cut-off time for boarding passes on the final ARK is coming soon.

    1. Dom says:

      God is greater than your scripture. The earth was created. But your idea of time is blasphemy at the very least, God isn’t limited by the pages of your book nor is the story of Jesus. The end of an age may be upon us and as happened before we will parish and those who survive (the meek) shall invent new stories of the creation.

  6. Marilyn sullivan says:

    Get used to it we are lied to because there’s a plan alien invasion thankyou Werner VON Braun,they want us to be scared and dumb idiots ha they want to tell us we are dummies no brains when you mentionUFO. If laugh,the people of this earth are waking up,it called the awakening!DUH!👍

  7. Sneevo says:

    I find it laughable that you still believe that we emerged from the primordial slime. To create a living cell, you need proteins, to create proteins you need amino acids. So what is the probability that all the correct atoms/molecules were in the right place at the right time to make just one amino acid molecule? .. so if you think that it is possible, how then does a cell accumulate hundreds of millions of diverse protein molecules? .. how does the nucleus form? .. how does the DNA form with over a billion base pairs? .. and how does that cell replicate?.

    I think the author of this article needs to do a course in molecular biology.

    1. Bob says:

      Agreed. The level of complexity in even simple life forms is amazing. Things don’t normally make themselves more complex. Things normally degrade themselves to their base elements. Complex life forms are not well understood by humans today. There is no way that random evolution could create the complexity of what we call life in the time that this planet has been here.
      .

    2. Ken Anderson says:

      I took the molecular biology course. I do think that was indeed the most convincing course. Plus the fact of chirality we learn about in organic chemistry. There HAD to have been intelligent intervention to avoid being just a bunch of randomness. My freshman level biology text stupidly stated that _reproduction_ evolved! WHAT?!!!!!!

  8. Bob says:

    For 80 years, Planet Earth has, and continues to, send megawatt power pulsed radar signals into space since World War II. That means that Earth is an easy target for anyone with a small antenna in an 80 light year radius. You wouldn’t need AI to tell you the signals are there. Earth is the loudest signal in space at those frequencies.

  9. Ken Anderson says:

    “Alternatively, if we really are alone, we should reflect on the unique beauty and fragility of life here on Earth.”
    Are we waiting to do this until we lose hope? “Hope springs eternal…” and all that, you know. We will NEVER finally conclude that we are alone, even if we are.

    …and we aren’t.