Seventy years ago, Italian-American nuclear physicist Enrico Fermi asked his colleagues a question during a lunchtime conversation. If life is common in our Universe, why can’t we see any evidence of its activity out there (aka. “where is everybody?”) Seventy years later, this question has launched just as many proposed resolutions as to how extraterrestrial intelligence (ETIs) could be common, yet go unnoticed by our instruments.
Some possibilities that have been considered are that humanity might be alone in the Universe, early to the party, or is not in a position to notice any yet. But in a recent study, Robin Hanson (creator of the Great Filter) and an interdisciplinary team offer a new model for determining when the aliens will get here. According to their study, humanity is early to the Universe and will meet others in 200 million to 2 billion years from now.
Continue reading “If Aliens Are Out There, We’ll Meet Them in a Few Hundred Million Years”
On October 19th, 2017, astronomers made the first-ever detection of an interstellar object (ISO) in our Solar System. This body, named 1I/2017 U1 (‘Oumuamua), was spotted shortly after it flew by Earth on its way to the outer Solar System. Years later, astronomers are still hypothesizing what this object could have been (an interstellar “dust bunny,” hydrogen iceberg, nitrogen icebergs), with Harvard Prof. Abraham Loeb going as far as to suggest that it might have been an extraterrestrial solar sail.
Roughly three years later, interest in extraterrestrial visitors has not subsided, in part because of the release of the Pentagon report on the existence of “Unidentified Aerial Phenomena.” This prompted Loeb and several of his fellow scientists to form the Galileo Project, a multi-national, multi-institutional research team dedicated to bringing the search for Extraterrestrial Technological Civilizations (ETC) into the mainstream.
Continue reading “A New Plan to Search for Extraterrestrial Artifacts at Earth and Across the Solar System”
In the Fall of 2017, the first known interstellar object passed through the Solar System, triggering a revolution in astronomy. Because of the amonolous nature of the object, astronomers from all over the world were at a loss to explain what it was. Neither comet, nor asteroid, nor any other conventional object appeared to fit the bill, leading to all kinds of “exotic” explanations.
A particularly exotic explanation was offered by Harvard Professor Avi Loeb and his former postdoc (Dr. Shmuel Bialy), who hypothesized that ‘Oumuamua could have been an extraterrestrial lightsail. Whereas most rebuttal papers questioned the evidence presented, a new study by astrophysicist and UCLA emeritus professor Ben Zuckerman questioned something else: why would an extraterrestrial civilization want to send a probe our way?
Continue reading “Oumuamua Isn’t an Alien Probe, Because Aliens can Learn Everything They Need About us With Telescopes”
On October 19th, 2017, astronomers from the Haleakala Observatory in Hawaii announced the first-ever detection of an interstellar object in our Solar System. In honor of the observatory that first spotted it, this object (designated 1I/2017 U1) was officially named ‘Oumuamua by the IAU – a Hawaiian term loosely translated as “Scout” (or, “a messenger from afar arriving first.”)
Multiple follow-up observations were made as ‘Oumuamua left our Solar System and countless research studies resulted. For the most part, these studies addressed the mystery of what ‘Oumuamua truly was: a comet, an asteroid, or something else entirely? Into this debate, Dr. Shmuel Bialy and Prof. Avi Loeb of the Harvard Institute for Theory and Computation (ITC) argued that ‘Oumuamua could have been an extraterrestrial probe!
Having spent the past few years presenting this controversial theory before the scientific and astronomical community, Prof. Loeb has since shared the story of how he came to it in his new book, Extraterrestrial: The First Sign of Intelligent Life Beyond Earth. The book is a seminal read, addresses the mystery of ‘Oumuamua, and (most importantly) urges readers to take seriously the possibility that an extraterrestrial encounter took place
Continue reading “A Review of “Extraterrestrial” by Prof. Avi Loeb”
In December of 2020, the world got a bit of a pre-holiday surprise when it was announced that astronomers at the Parkes radio telescope in Australia had detected a “tantalizing” signal coming from Proxima Centauri (the red dwarf companion of the Alpha Centauri system). Afterward, researchers at Breakthrough Listen consulted the data on the signal – Breakthrough Listen Candidate 1 (BLC1) – and noted the same curious features.
However, the scientific community has since announced that the signal is unlikely to be anything other than the result of natural phenomena. This was also the conclusion reached by Amir Siraj and Prof. Abraham Loeb of Harvard University after they conducted a probability assessment on BLC1. Like the vast majority of candidate radio signals discovered to date, this one appears to be just the forces of nature saying hello.
Continue reading “According to the Math, it’s Highly Unlikely That an Intelligent Civilization is Located at Alpha Centauri”
Recently at UT, author Matt Williams has been writing a series called “Beyond Fermi’s Paradox”, which takes a look at possible resolutions to one of the most famous questions in science: “Where is everybody?” As Matt discusses, there are multiple hypothetical solutions, but there may eventually come a day when we can definitively answer it.
Consideration of that day opens up a whole host of new questions, not the least of which is what will an intelligent civilization we find be like? Carl Sagan popularized the notion that it is very unlikely that any extraterrestrial civilization would be equivalent to ours in terms of technological progress. What he did not address was the relative age of the civilization and what that might mean in terms of their interest in communicating with us. Now a team of astronomers have come up with an answer to that question using one of the most underappreciated mathematical tools: statistics. Their model provides a simple answer: any intelligent civilization is likely older than us, and potentially much older.
Continue reading “The First Civilization We Contact Will Have Been Around Much Longer Than Humanity”
The Vera C. Rubin Observatory, formerly the Large Synoptic Survey Telescope (LSST), will commence operations sometime next year. Not wanting to let a perfectly good acronym go to waste, its first campaign will be known as the Legacy Survey of Space and Time (LSST). This ten-year survey will study everything from dark matter and dark energy to the formation of the Milky Way, and small objects in our Solar System.
According to a new study by Amir Siraj and Prof. Abraham Loeb of Harvard University, another benefit of this survey will be the discovery of interstellar objects that regularly enter the Solar Systems. These results, when combined with physical characterizations of the objects, will teach us a great deal about the origin and nature of planetary systems (and could even help us spot an alien probe or two!)
Continue reading “Vera Rubin Should be Able to Detect a Couple of Interstellar Objects a Month”
Using the Atacama Large Millimeter/submillimeter Array (ALMA), a team of scientists has identified a mysterious molecule in Titan’s atmosphere. It’s called cyclopropenylidene (C3H2), a simple carbon-based compound that has never been seen in an atmosphere before. According to the team’s study published in The Astronomical Journal, this molecule could be a precursor to more complex compounds that could indicate possible life on Titan.
Similarly, Dr. Catherine Neish of the University of Western Ontario’s Institute for Earth and Space Exploration (Western Space) and her colleagues in the European Space Agency (ESA) found that Titan has other chemicals that could be the ingredients for exotic life forms. In their study, which appeared in Astronomy & Astrophysics, they present Cassini mission data that revealed the composition of impact craters on Titan’s surface.
Continue reading “Titan’s Atmosphere Has All the Ingredients For Life. But Not Life as We Know It”
In the past few decades, the study of exoplanets has grown by leaps and bounds, with 4296 confirmed discoveries in 3,188 systems and an additional 5,634 candidates awaiting confirmation. Because of this, scientists have been able to get a better idea about the number of potentially-habitable planets that could be out there. A popular target is stars like our own, which are known as G-type yellow dwarfs.
Recently, an international team of scientists (led by researchers from the NASA Ames Research Center) combined data from by the now-defunct Kepler Space Telescope and the European Space Agency’s (ESA) Gaia Observatory. What this revealed is that half of the Sun-like stars in our Universe could have rocky, potentially-habitable planets, the closest of which could be in our cosmic backyard!
Continue reading “Based on Kepler Data, There’s a 95% Chance of an Earth-Like Planet Within 20 Light-Years”