Extraterrestrial Archives

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.

September 29, 2023September 29, 2023 by Laurence Tognetti

Since Aliens Obey the Laws of Physics, Can We Guess What They Look Like?

Since time immemorial, humans have gazed up at the stars and wondered if we’re alone in the universe. We have asked if there are other intelligent beings out there in the vastness of the cosmos, also known as extraterrestrial intelligence (ET). Yet, despite our best efforts, we have yet to confirm the existence of ET outside of the Earth. While the search continues, it’s fair to speculate if they might look “human” or humanoid in appearance, or if they could look like something else entirely. Here, we present a general examination and discussion with astrobiologists pertaining to what ET might look like and what environmental parameters (e.g., gravity, atmospheric makeup, stellar activity) might cause them to evolve differently than humans.

September 13, 2023September 13, 2023 by Evan Gough

Could We Find Aliens Terraforming Other Worlds?

Artist's conception of a terraformed Mars. Credit: Ittiz/Wikimedia Commons

The first early humans to use fire had no inkling of what it would lead to.

Fire was one of our first technologies, and humans have been making changes to their environments since the advent of controlled fire hundreds of thousands of years ago. Fast forward to current times, and our modern technological and global civilization is changing the Earth’s entire biosphere. From carbon emissions that acidify the oceans and weaken the shells of marine life to microplastics that find their way into organisms’ bloodstreams, our technology is intersecting, or combining, with the biosphere.

This has spawned a useful word: biotechnosphere.

August 9, 2023April 14, 2024 by Matt Williams

Penn State SETI Symposium Opens with Commemoration of Dr. Frank Drake

Dr. Frank Drake (1930 -2022). Credit: Danielle Futselaar

Is humanity alone in the Universe? Is anyone out there? Where is everybody? And what happens if and when we make contact with them? These and other questions were the subjects of the 2023 Penn State SETI Symposium hosted by the Penn State Extraterrestrial Intelligence Center (PSETI) from June 19th-22nd, 2023. The event featured prominent speakers from various research fields and disciplines discussing the challenges, history, and future of SETI. In the great tradition established by Dr. Frank Drake, they also addressed key issues related to the search for intelligent life and what we might find someday.

The summit opened with a series of overviews, a review of the past year (since the last summit), and a presentation by Dr. Rebecca Charbonneau, a science historian and Jansky Fellow at the National Radio Astronomy Observatory (NRAO). Her presentation, titled “Frank Drake and his Place in History,” provided a retrospective on the life and accomplishments of famed radio astronomer and SETI pioneer Dr. Frank Drake (for whom the Drake Equation is named), how he altered the character of the field, and how history will remember him.

June 2, 2023June 6, 2023 by Matt Williams

Astronomers are Searching for a Galaxy-Wide Transmitter Beacon at the Center of the Milky Way

Artist's impression of a Dyson Sphere, an proposed alien megastructure that is the target of SETI surveys. Finding one of these qualifies in a "first contact" scenario. Credit: Breakthrough Listen / Danielle Futselaar

It has been over sixty years since the first Search for Extraterrestrial Intelligence (SETI) survey occurred. This was Project Ozma, a survey led by Dr. Frank Drake (who devised the Drake Equation) that used the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia, to listen for radio transmissions from Epsilon Eridani and Tau Ceti. While the search revealed nothing of interest, it paved the way for decades of research, theory, and attempts to find evidence of technological activity (aka. “technosignatures”).

The search continues today, with researchers using next-generation instruments and analytical methods to find the “needle in the cosmic haystack.” This is the purpose behind Breakthrough Listen Investigation for Periodic Spectral Signals (BLIPSS), a collaborative SETI project led by Cornell graduate student Akshay Suresh to look for technosignatures at the center of the Milky Way. In a recent paper, Suresh and his team shared their initial findings, which were made possible thanks to data obtained by the Greenbank Observatory and a proprietary algorithm they developed.

May 30, 2023May 30, 2023 by Matt Williams

A Sign from Space Simulates What it Would be Like to Get a Message from Aliens!

A Sign in Space is a worldwide artistic project that will inspire a conversation about the possibility of First Contact. Credit: SETI Institute

Someday, humanity might receive a message from space that will answer one of the greatest existential questions: is anybody out there? Regardless of the content, a message from an extraterrestrial civilization will be the single greatest event in human history. How would such an event happen, and how would it play out? What will be the repercussions of billions of people suddenly learning that we are NOT alone in the Universe? This question has inspired countless works of science fiction and scientific studies that have attempted to predict (and even quantify) our collective reaction.

This was the purpose behind A Sign in Space, a revolutionary art project designed to simulate a First Contact scenario. This project was the brainchild of Daniela de Paulis, a contemporary artist, and licensed radio operator currently serving as the Artist in Residence at the SETI Institute and the Green Bank Observatory. Together with a team of international experts, including SETI researchers, space scientists, and artists, de Paulis created this campaign to engage the global SETI community and the general public about the possibility of First Contact.

January 12, 2023January 12, 2023 by Evan Gough

Game of Probes: The First Probe Sent to Another Civilization Won’t Be the First to Arrive

An artist's concept of Voyager 1's view of the Solar System. Voyager 1 is one of our first interstellar probes, though it's an inadvertent one. It has no particular destination. Credit: NASA, ESA, and J. Zachary and S. Redfield (Wesleyan University); Artist's Illustration Credit: NASA, ESA, and G. Bacon (STScI).

If we ever detect an Extraterrestrial Civilization (ETC) and start communicating with them, the messages could take years, decades, or even centuries to travel back and forth. We face a challenging 49-minute long delay just communicating with the Juno spacecraft orbiting Jupiter, and that’s well within our Solar System. Communicating with an ETC that’s hundreds of light-years away or even further is a daunting task.

It’s even worse if we’re sending probes.

December 19, 2022December 19, 2022 by Matt Williams

Gravitational Wave Observatories Could Search for Warp Drive Signatures

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

In 2016, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced that they had made the first confirmed detection of gravitational waves (GWs). This discovery confirmed a prediction made a century before by Einstein and his Theory of General Relativity and opened the door to a whole new field of astrophysical research. By studying the waves caused by the merger of massive objects, scientists could probe the interior of neutron stars, detect dark matter, and discover new particles around supermassive black holes (SMBHs).

According to new research led by the Advanced Propulsion Laboratory at Applied Physics (APL-AP), GWs could also be used in the Search for Extraterrestrial Intelligence (SETI). As they state in their paper, LIGO and other observatories (like Virgo and KAGRA) have the potential to look for GWs created by Rapid And/or Massive Accelerating spacecraft (RAMAcraft). By combining the power of these and next-generation observatories, we could create a RAMAcraft Detection And Ranging (RAMADAR) system that could probe all the stars in the Milky Way (100 to 200 billion) for signs of warp-drive-like signatures.

November 29, 2022November 29, 2022 by Laurence Tognetti

What if we’re truly alone?

At least once, you’ve looked up at the night sky and asked the same longstanding question we’ve all asked at least once, “Are we alone?” With all those points of light out there, we can’t be the only intelligent beings in the universe, right? There must be at least one technological civilization aside from us in the great vastness that we call the cosmos.