SETI Archives

July 26, 2022July 26, 2022 by Matt Williams

Before we Develop Self-Replicating Machines to Explore the Universe, we Should Figure out how to Turn Them off Again

An early NASA concept of an interstellar space probe. Credit: NASA/Johns Hopkins University Applied Physics Laboratory

In 1948/49, famed computer scientist, engineer, and physicist John von Neumann introduced the world to his revolutionary idea for a species of self-replicating robots (aka. “Universal Assemblers”). In time, researchers involved in the Search for Extraterrestrial Intelligence (SETI) adopted this idea, stating that self-replicating probes would be an effective way to explore the cosmos and that an advanced species may be doing this already. Among SETI researchers, “Von Neumann probes” (as they’ve come to be known) are considered a viable indication of technologically advanced species (technosignature).

Given the rate of progress with robotics, it’s likely just a matter of time before humanity can deploy Von Neumann probes, and the range of applications is endless. But what about the safety implications? In a recent study by Carleton University Professor Alex Ellery explores the potential harm that Von Neumann Probes could have. In particular, Ellery considers the prospect of runaway population growth (aka. the “grey goo problem”) and how a series of biologically-inspired controls that impose a cap on their replication cycles would prevent that.

July 9, 2022July 12, 2022 by Laurence Tognetti

Snooping on Alien Messages Passing Through the Solar System

Researchers at Penn State University have studied a new technique that could use a star’s ability to focus and magnify communications which could be passing through our own solar system, and has been accepted for publication in The Astronomical Journal and was part of a graduate course at Penn State covering the Search for Extraterrestrial Intelligence (SETI. The study describes our Sun as potentially acting as a kind of node as part of an interstellar communication network involving probes or relays near our Sun, acting like cellular telephone towers in space.

June 22, 2022June 23, 2022 by Matt Williams

Chinese Astronomers Detect an Interesting (But NOT Alien) Signal With the FAST Radio Observatory

The Five-hundred-metre Aperture Spherical Telescope (FAST) has just finished construction in the southwestern province of Guizhou. Credit: FAST

The 500-Meter Aperture Spherical Telescope (FAST), (aka. Tianyan, “Eye of Heaven”), is the largest radio observatory in the world. Since the observatory became operational in January 2020, this facility has made significant contributions to radio astronomy and the Search for Extraterrestrial Intelligence (SETI). In particular, the observatory has been instrumental in detecting Fast Radio Burts (FRBs) and other cosmic phenomena that could be (but probably aren’t) possible indications of extraterrestrial communications.

Last week, while sifting through FAST data, the China Extraterrestrial Civilization Research Group (CECRG) from Beijing Normal University revealed that they discovered several signals that might be artificial in origin (a possible indication of an advanced civilization). These signals consisted of narrow-band electromagnetic radio transmission and were considered one of the best candidates for an extraterrestrial signal. Ah, but there’s a snag. According to subsequent news releases, those radio transmissions were apparently from Earth!

June 22, 2022June 22, 2022 by Brian Koberlein

Another few Weeks of Observations Could Tell us if the Wow! Signal Repeats

A new study from the Center for Planetary Science claims that a comet may be responsible fr the famous Wow! Signal. Credit: NASA/JPL-Caltech

In the decades-long search for extraterrestrial intelligence, there has never been confirmed evidence of an alien signal. There have, however, been a few tantalizing mysteries. Perhaps the greatest of these is known as the Wow Signal.

June 15, 2022June 15, 2022 by Matt Williams

There Could Be Four Hostile Civilizations in the Milky Way

This artists’s cartoon view gives an impression of how common planets are around the stars in the Milky Way. The planets, their orbits and their host stars are all vastly magnified compared to their real separations. A six-year search that surveyed millions of stars using the microlensing technique concluded that planets around stars are the rule rather than the exception. The average number of planets per star is greater than one.

In 1977, the Big Ear Radio Telescope at Ohio State University picked up a strong narrowband signal from space. The signal was a continuous radio wave that was very strong in intensity and frequency and had many expected characteristics of an extraterrestrial transmission. This event would come to be known as the Wow! Signal, and it remains the strongest candidate for a message sent by an extraterrestrial civilization. Unfortunately, all attempts to pinpoint the source of the signal (or detect it again) have failed.

This led many astronomers and theorists to speculate as to the origin of the signal and what type of civilization may have sent it. In a recent series of papers, amateur astronomer and science communicator Alberto Caballero offered some fresh insights into the Wow! Signal and extraterrestrial intelligence in our cosmic neighborhood. In the first paper, he surveyed nearby Sun-like stars to identify a possible source for the signal. In the second, he estimates the prevalence of hostile extraterrestrial civilizations in the Milky Way Galaxy and the likelihood that they’ll invade us.

May 2, 2022May 2, 2022 by Evan Gough

Humanity Will Need to Survive About 400,000 Years if We Want any Chance of Hearing From an Alien Civilization

Standing beside the Milky Way. Drowming out the night sky blocks us off from nature, and that's not good for humans. Credit: P. Horálek/ESO

If there are so many galaxies, stars, and planets, where are all the aliens, and why haven’t we heard from them? Those are the simple questions at the heart of the Fermi Paradox. In a new paper, a pair of researchers ask the next obvious question: how long will we have to survive to hear from another alien civilization?

Their answer? 400,000 years.

April 18, 2022April 18, 2022 by Brian Koberlein

When Will Humanity Become a Type I Civilization?

Dyson Sphere as Depicted in the videogame "Stellaris", developed and published by Paradox Interactive. Used with permission. Screenshot by author

There are several ways we can measure the progress of human civilization. Population growth, the rise and fall of empires, our technological ability to reach for the stars. But one simple measure is to calculate the amount of energy humans use at any given time. As humanity has spread and advanced, our ability to harness energy is one of our most useful skills. If one assumes civilizations on other planets might possess similar skills, the energy consumption of a species is a good rough measure of its technological prowess. This is the idea behind the Kardashev Scale.

April 17, 2022April 17, 2022 by Matt Williams

SETI Researchers can now Scan all Data at the Very Large Array for any Evidence of Alien Transmissions

The Karl G. Jansky Very Large Array, located in central New Mexico. Credit: NRAO

On February 14^th, 2020, the SETI Insitute and the National Radio Astronomy Observatory (NRAO) announced a new partnership, which they appropriately named the Commensal Open-Source Multimode Interferometer Cluster Search for Extraterrestrial Intelligence (COSMIC SETI). This partnership will allow the Karl G. Jansky Very Large Array (VLA) to participate in the Search for Extraterrestrial Intelligence (SETI) for the first time in its history.

In recent weeks, the project took a big step forward with the installation of fiber optic amplifiers and splitters on all VLA antennas, which give COSMIC access to the data streams from the entire VLA. Once this digital backend is online, COSMIC will have access to all data provided by the VLAs 27 radio antennas, which will be able to conduct observations 24/7. In the process, COSMIC SETI will examine around 40 million stars in the Milky Way for possible signs of intelligent life.

April 7, 2022April 7, 2022 by Matt Williams

Canada's CHIME is Getting More Observatories to Search for Fast Radio Bursts

CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.

In 2017, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) began to gather light from the Universe to address some of the biggest questions and astrophysics and cosmology. Located at the Dominion Radio Astrophysical Observatory (DRAO) in British Columbia, this interferometric radio telescope has been a game-changer for studying Fast Radio Bursts (FRBs), which remain one of the most mysterious cosmic mysteries facing astronomers today.

In the near future, CHIME will be getting an expansion that will help it more accurately identify where FRBs are coming from. This will consist of a new radio telescope outrigger located at the SETI Institute’s Hat Creek Radio Observatory (HCRO), new outriggers near Princeton, British Columbia, and at the Green Bank Observatory in West Virginia. These will work with the main CHIME telescope to localize CHIME-detected FRBs precisely in the night sky.

April 7, 2022April 7, 2022 by Matt Williams

If Aliens Were Sending us Signals, This is What They Might Look Like

For over sixty years, scientists have been searching the cosmos for possible signs of radio transmission that would indicate the existence of extraterrestrial intelligence (ETI). In that time, the technology and methods have matured considerably, but the greatest challenges remain. In addition to having never detected a radio signal of extraterrestrial origin, there is a wide range of possible forms that such a broadcast could take.

In short, SETI researchers must assume what a signal would look like, but without the benefit of any known examples. Recently, an international team led by the University of California Berkeley and the SETI Institute developed a new machine learning tool that simulates what a message from extraterrestrial intelligence (ETI) might look like. It’s known as Setigen, an open-source library that could be a game-changer for future SETI research!