SETI Archives

October 28, 2024October 28, 2024 by Matt Williams

Remember that “Alien Signal” Sent by the ExoMars Orbiter Last Year? It’s Just Been Decoded

The Sign in Space message has finally been decoded. Credit: A Sign in Space

In May 2023, the ESA’s Exomars Trace Gas Orbiter (TGO), currently in orbit around Mars, sent a signal to Earth to simulate a possible extraterrestrial transmission. As part of the multidisciplinary art project “A Sign in Space,” the purpose was to engage citizen scientists in helping to decode it. The campaign was inspired by Cosmicomics by Italian writer/journalist Italo Calvino, a series of short stories exploring various scientific principles. The project is partnered with the SETI Institute, the Green Bank Observatory, the European Space Agency (ESA), and the Istituto Nazionale di Astrofisica (INAF).

After three radio astronomy observatories on Earth intercepted the message, the challenge was to extract the message from the raw data of the radio signal and then decode it. After ten days, more than 5000 citizen scientists worldwide gathered online and used their combined resources to extract the signal. After a year of attempts, two U.S. citizens – the father-daughter team of Ken and Keli Chaffin – managed to crack the code after days of simulations. They discovered that the message consisted of five clusters of white dots and lattices against a black background, suggesting cellular formation and life!

September 21, 2024September 21, 2024 by Matt Williams

Advanced Civilizations Will Overheat Their Planets Within 1,000 Years

Global temperature increases over the past thirty years, visualized. Credit: NOAA/NCEI

Earth’s average global temperatures have been steadily increasing since the Industrial Revolution. According to the National Oceanic and Atmospheric Agency (NOAA), Earth has been heating up at a rate of 0.06 °C (0.11 °F) per decade since 1850 – or about 1.11 °C (2 °F) in total. Since 1982, the average annual increase has been 0.20 °C (0.36 °F) per decade, more than three times as fast. What’s more, this trend is projected to increase by between 1.5 and 2 °C (2.7 to 3.6 °F) by mid-century, possibly more! This is a direct consequence of burning fossil fuels, which has increased exponentially since the mid-19th century.

Depending on the extent of temperature increases, the impact on Earth’s habitability could be catastrophic. In a recent study, a team of scientists examined how temperature increases are a long-term issue facing advanced civilizations and not just a matter of fossil fuel consumption. As they argue, rising planetary temperatures could be an inevitable result of the exponential growth of energy consumption. Their findings could have serious implications for astrobiology and the Search for Extraterrestrial Intelligence (SETI).

September 11, 2024September 11, 2024 by Matt Williams

Projecting what Earth will Look Like 1000 years from now Could Assist in the Search for Advanced Civilizations

Earth’s immature biosphere and mature biosphere stages. The mature biosphere stage was only possible once photosynthetic organisms created feedback with Earth’s non-biological processes, oxygenating the atmosphere and creating an ozone layer. Image Credit: University of Rochester illustration / Michael Osadciw

The Search for Extraterrestrial Intelligence (SETI) is regularly plagued by the fact that humanity has a very limited perspective on civilization and the nature of intelligence itself. When it comes right down to it, the only examples we have to go on are “life as we know it” (aka. Earth organisms) and human civilization. On top of that, given the age of the Universe and the time life has had to evolve on other planets, it is a foregone conclusion that any advanced life in our galaxy would be older than humanity. Luckily, this presents an opportunity to develop and test theoretical frameworks in the field.

To paraphrase Freeman Dyson, if we can conceive of a concept (and the physics are sound), an advanced species will likely have built it already. In this respect, imagining where humanity will be centuries or eons from now could provide potential “technosignatures” to look for. In a recent paper, a team from the Blue Marble Space Institute of Science (BMSIS) and NASA’s Goddard Space Flight Center modeled a series of scenarios that attempt to predict what humanity’s “technosphere” could look like 1,000 years from now. Their research could have implications for future SETI studies.

August 29, 2024August 29, 2024 by Mark Thompson

Giant Low-Frequency Scan Searches for Aliens in 2,800 Galaxies

One of the tiles making up the 32T, a prototype instrument for the Murchison Widefield Array. Natasha Hurley-Walker

The search for extraterrestrial intelligence (SETI) has fascinated us for decades. Now a team of researchers have used the Murchison Widefield Array in Australia to scan great swathes of sky for alien signals. Unusually for a SETI project, this one focussed attention on 2,800 galaxies instead of stars within our own. They have been on the lookout for advanced civilisations that are broadcasting their existence using the power of an entire star. Alas they weren’t successful but its an exciting new way to search for alien intelligence.

August 22, 2024August 22, 2024 by Matt Williams

New Study Proposes how a Black Hole in Orbit Around a Planet Could be a Sign of an Advanced Civilization.

Ray traced shadow of a spinning and charged black hole. Credit: Simon Tyran, CC BY-SA 4.0

In 1971, English mathematical physicist and Nobel-prize winner Roger Penrose proposed how energy could be extracted from a rotating black hole. He argued that this could be done by building a harness around the black hole’s accretion disk, where infalling matter is accelerated to close to the speed of light, triggering the release of energy in multiple wavelengths. Since then, multiple researchers have suggested that advanced civilizations could use this method (the Penrose Process) to power their civilization and that this represents a technosignature we should be on the lookout for.

Examples include John M. Smart’s Transcension Hypothesis, a proposed resolution to the Fermi Paradox where he suggested advanced intelligence may migrate to the region surrounding black holes to take advantage of the energy available. The latest comes from Harvard Professor Avi Loeb, who proposed in a recent paper how advanced civilizations could rely on a “Black Hole Moon” to provide their home planet with power indefinitely. The way this black hole would illuminate the planet it orbits, he argues, would constitute a potential technosignature for future SETI surveys.

August 7, 2024August 9, 2024 by Matt Williams

New Study Suggests that Our Galaxy is Crowded or Empty. Both are Equally Terrifying!

Gaia's all-sky view of our Milky Way Galaxy and neighbouring galaxies, based on measurements of nearly 1.7 billion stars. The map shows the total brightness and colour of stars observed by the ESA satellite in each portion of the sky between July 2014 and May 2016. Brighter regions indicate denser concentrations of especially bright stars, while darker regions correspond to patches of the sky where fewer bright stars are observed. The colour representation is obtained by combining the total amount of light with the amount of blue and red light recorded by Gaia in each patch of the sky. The bright horizontal structure that dominates the image is the Galactic plane, the flattened disc that hosts most of the stars in our home Galaxy. In the middle of the image, the Galactic centre appears vivid and teeming with stars. More information on: http://sci.esa.int/gaia/60169-gaia-s-sky-in-colour/

Is there intelligent life in the Universe? And if so, just how common is it? Or perhaps the question should be, what are the odds that those engaged in the Search for Extraterrestrial Intelligence (SETI) will encounter it someday? For decades, scientists have hotly debated this topic, and no shortage of ink has been spilled on the subject. From the many papers and studies that have been written on the subject, two main camps have emerged: those who believe life is common in our galaxy (aka. SETI Optimists) and those who maintain that extraterrestrial intelligence is either rare or non-existent (SETI Pessimists).

In a recent paper, David Kipping (Prof. “Cool Worlds” himself) and Geraint Lewis examined this debate more closely and offered a fresh take based on a form of probability analysis known as Jayne’s Experiment. By applying this method to astrobiology and the Drake Equation, they concluded that the existence of intelligent life in our galaxy may be an “all or nothing” proposition. To quote the late and great scientist and science fiction author Arthur C. Clarke: “Two possibilities exist: either we are alone in the Universe, or we are not. Both are equally terrifying.”

August 6, 2024August 6, 2024 by Mark Thompson

If Advanced Civilizations Using Quantum Communications, Is That Why We’ve Never Seen Them?

Establishing communication with an alien intelligence is one of the news items I, and I’m sure many others, long to see. Since we have started the search for advanced civilisations we have tried numerous ways to detect their transmissions but to date, unsuccessfully. A new paper suggests quantum communication may be the ideal method for interstellar communication. It has many benefits but the challenge is that it would require a receiver over 100km across to pick up a signal. Alas they know we don’t have that tech yet!

April 9, 2024April 9, 2024 by Andy Tomaswick

The Seven Most Intriguing Worlds to Search for Advanced Civilizations (So Far)

Sometimes, the easy calculations are the most interesting. A recent paper from Balázs Bradák of Kobe University in Japan is a case in point. In it, he takes an admittedly simplistic approach but comes up with seven known exoplanets that could hold the key to the biggest question of them all – are we alone?

March 22, 2024March 23, 2024 by Alan Boyle

Starshot … Not? Get a Reality Check on the Search for Alien Civilizations

Zine Tseng as Chinese radio astronomer, sitting at control panel for antenna — Zine Tseng plays a Chinese radio astronomer in "3 Body Problem." (Credit: Ed Miller / Netflix © 2024)

Fortunately, the real-world search for signs of extraterrestrial civilizations doesn’t have to deal with an alien armada like the one that’s on its way to Earth in “3 Body Problem,” the Netflix streaming series based on Chinese sci-fi author Cixin Liu’s award-winning novels. But the trajectory of the search can have almost as many twists and turns as a curvature-drive trip from the fictional San-Ti star system.

February 22, 2024February 22, 2024 by Brian Koberlein

We Could Snoop on Extraterrestrial Communications Networks

The Atacama Large Millimeter/submillimeter Array (ALMA). Credit: C. Padilla, NRAO/AUI/NSF

The conditions for life throughout the Universe are so plentiful that it seems reasonable to presume there must be extra-terrestrial civilizations in the galaxy. But if that’s true, where are they? The Search for Extra-terrestrial Intelligence (SETI) program and others have long sought to find signals from these civilizations, but so far there has been nothing conclusive. Part of the challenge is that we don’t know what the nature of an alien signal might be. It’s a bit like finding a needle in a haystack when you don’t know what the needle looks like. Fortunately, any alien civilization would still be bound by the same physical laws we are, and we can use that to consider what might be possible. One way to better our odds of finding something would be to focus not on a direct signal from a single world, but the broader echos of an interstellar network of signals.