Extraterrestrial Archives

November 13, 2024November 13, 2024 by Matt Williams

New Study Examines How Extraterrestrial Civilizations Could Become “Stellarvores.”

Artist's impression of accretion in a binary system. Credit: ESO/L. Calçada

One of the most challenging aspects of astrobiology and the Search for Extraterrestrial Intelligence (SETI) is anticipating what life and extraterrestrial civilizations will look like. Invariably, we have only one example of a planet that supports life (Earth) and one example of a technologically advanced civilization (humanity) upon which to base our theories. As for more advanced civilizations, which statistically seems more likely, scientists are limited to projections of our own development. However, these same projections offer constraints on what SETI researchers should search for and provide hints about our future development.

In a series of papers led by the Blue Marble Space Institute of Science (BMSIS), a team of researchers examines what Earth’s level of technological development (aka. “technosphere”) will look like in the future. In the most recent installment, they offer a reinterpretation of the Kardashev Scale, which suggests that civilizations expand to harness greater levels of energy (planet, host star, and galaxy). Instead, they suggest that the Kardashev Scale establishes upper limits on the amount of stellar energy a civilization can harness (a “luminosity limit”) and that civilizations might circumvent this by harnessing stellar mass directly.

November 11, 2024November 12, 2024 by Matt Williams

Project Hyperion is Seeking Ideas for Building Humanity’s First Generation Ship

Project Hyperion is the first design competition for a generation ship. Credit: Maciej Rebisz/Michel Lamontagne

The dream of traversing the depths of space and planting the seed of human civilization on another planet has existed for generations. For long as we’ve known that most stars in the Universe are likely to have their own system of planets, there have been those who advocated that we explore them (and even settle on them). With the dawn of the Space Age, this idea was no longer just the stuff of science fiction and became a matter of scientific study. Unfortunately, the challenges of venturing beyond Earth and reaching another star system are myriad.

When it comes down to it, there are only two ways to send crewed missions to exoplanets. The first is to develop advanced propulsion systems that can achieve relativistic speeds (a fraction of the speed of light). The second involves building spacecraft that can sustain crews for generations – aka. a Generation Ship (or Worldship). On November 1st, 2024, Project Hyperion launched a design competition for crewed interstellar travel via generation ships that would rely on current and near-future technologies. The competition is open to the public and will award a total of $10,000 (USD) for innovative concepts.

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.”

July 9, 2024July 9, 2024 by Mark Thompson

Do Planets Have the Raw Ingredients for Life? The Answer is in their Stars

Finding planets that already have, or have the ingredients for intelligent life is a real challenge. It is exciting that new telescopes and spacecraft are in development that will start to identify candidate planets. Undertaking these observations will take significant amounts of telescope time so we need to find some way to prioritise which ones to look at first. A new paper has been published that suggests we can study the host stars first for the necessary raw elements giving a more efficient way to hunt for similar worlds to Earth.

July 9, 2024July 9, 2024 by Mark Thompson

The Rugged Desert Moss Best Equipped to Survive on Mars

For decades, we have seen Mars as a desolate landscape devoid of any signs of life. Attempt to identify ways of growing plants and food on the red planet have focussed on greenhouse like structures to enable plants to survive, that is, until now! A desert moss called ‘Syntrichia caninervis’ has been identified and it can grown in extreme environments like Antarctica and the Mojave Desert. A new study revealed the moss can survive Mars-like environments too including low temperatures, high levels of radiation and drought.

May 22, 2024May 22, 2024 by Evan Gough

Could Alien Solar Panels Be Technosignatures?

This image shows the Westlands Solar Park in the San Joaquin Valley. Could massive solar farms create a distinct technosignature? Image Credit: Westlands Solar Park

If alien technological civilizations exist, they almost certainly use solar energy. Along with wind, it’s the cleanest, most accessible form of energy, at least here on Earth. Driven by technological advances and mass production, solar energy on Earth is expanding rapidly.

It seems likely that ETIs (Extraterrestrial Intelligence) using widespread solar energy on their planet could make their presence known to us.

May 9, 2024May 9, 2024 by Evan Gough

Astronomers are on the Hunt for Dyson Spheres

Artist's impression of a Dyson Sphere. The construction of such a massive engineering structure would create a technosignature that could be detected by humanity. Credit: SentientDevelopments.com/Eburacum45

There’s something poetic about humanity’s attempt to detect other civilizations somewhere in the Milky Way’s expanse. There’s also something futile about it. But we’re not going to stop. There’s little doubt about that.

One group of scientists thinks that we may already have detected technosignatures from a technological civilization’s Dyson Spheres, but the detection is hidden in our vast troves of astronomical data.

February 28, 2024February 28, 2024 by Mark Thompson

An AI Simulated Interactions Between Different Kinds of Advanced Civilizations

Simulation of interactions with alien civilisations

The possibility for life beyond the Earth has captivated us for hundreds of years. It has been on the mind of science fiction writers too as our imaginations have explored the myriad possibilities of extraterrestrial life. But what would it really be like if/when we finally meet one; would it lead to war or peace? Researchers have used a complex language model to simulate the first conversations with civilisations from pacifists to militarists and the outcomes revealed interesting challenges.

February 27, 2024February 27, 2024 by Evan Gough

Some Intelligent Civilizations Will Be Trapped on their Worlds

With thousands of exoplanets discovered so far, astronomers are learning how different planets can be. What if intelligent alien civilizations arise on extremely different habitable worlds? Some civilizations could develop space exploration technologies, but others would be trapped underwater, under ice, or in enormous gravity wells. How could they escape? Image Credit: DALL-E

Evolution has produced a wondrously diverse variety of lifeforms here on Earth. It just so happens that talking primates with opposable thumbs rose to the top and are building a spacefaring civilization. And we’re land-dwellers. But what about other planets? If the dominant species on an ocean world builds a technological civilization of some sort, would they be able to escape their ocean home and explore space?

January 8, 2024January 8, 2024 by Evan Gough

Can Alien Civilizations Detect Humanity?

Is anyone out there? A new study examines how likely it is that an advanced ETI can "see" us. Image Credit: Jon Hrubesch

One of the fascinating things about being a human in this age is that we can do more than wonder about other life and other civilizations. We can actually look for them, although there are obvious limitations to our search. But what’s equally fascinating is that we can wonder if others can see us.