The Truth About The Exotica Catalog Used To Search For Alien Life

At this point, science fiction has treated us with almost limitless visions of alien life. We've seen rubber-headed Klingons from "Star Trek," tentacled Cthulhus like those in "War of the Worlds," interplanetary hunter-slayers like in 1987's "Predator," and genetically forged killers like in "Aliens": The list goes on and on. 

Meanwhile, in legitimate scientific circles, researchers have been making a concerted effort over decades to search for alien life  — albeit with fewer space suits and ray guns. The still-discussed 1977 Wow! Signal illustrates how scientists, like those at the SETI (Search for Extraterrestrial Intelligence) Institute, scour the sky for civilization-indicating signals such as unusual radio waves, per Astronomy. Astrobiology is a field of study that investigates similarities between extreme environments on Earth and those in space to look for conditions where life might evolve, as the National Center for Science Education describes. Some astronomers search for giant evidence of spacefaring civilizations — like Dyson spheres or Dyson swarms encasing entire stars — as Popular Mechanics describes.

With such a spectrum of viable ways to search for alien life, some researchers have taken to compiling a giant, handy-dandy compendium of terms, methods, anomalies, and more, related to the extraterrestrial hunt, as EarthSky points out. Dubbed the "Exotica Catalog," the goal is simple: Make a list of "one of everything" we've ever observed in the universe.  

The Exotica Catalog comes to us from Breakthrough Listen, "the largest ever scientific research program aimed at finding evidence of civilizations beyond Earth," as their website puts it. They're not exaggerating, either. The 10-year, $100-million project was launched by Professor Stephen Hawking himself in 2015, in conjunction with Israeli entrepreneur Yuri Milner, to "reinvigorate the search for life in the universe," as the original project announcement says. Breakthrough Listen is currently surveying an astonishing 1 million stars closest to Earth, including those in the nearest 100 galaxies, using state-of-the-art radio coverage, analytical software, and spectrometers that can spot "the energy of a normal household bulb from 25 trillion miles away."   

Breakthrough Listen is just one project within the greater Breakthrough Initiatives endeavor. In addition, Breakthrough Message is a $1 million project with a similar goal to the Golden Record shipped with NASA's Voyager 1 and 2 spacecrafts in 1977, as Smithsonian Magazine notes. As a refresher, musical selections and images from around the world, sounds, greetings in both ancient and modern languages, and more, were chosen by a team headed up by renowned astrophysicist Carl Sagan and intended for an advanced alien species to understand (per NASA). 

Breakthrough Watch, on the other hand, is a more fine-toothed survey of Earth-like planets in our nearer galactic vicinity of 20 light-years, particularly our closest neighboring star, Alpha Centauri. Finally, Breakthrough Starshot is aimed at researching and providing a "proof of concept" for a spacecraft that can travel up to 20% light-speed. 

The Exotica Catalog itself, compiled by Breakthrough Listen, is a 122-page, free-to-the-public document available online under its proper name, "One of Everything: The Breakthrough Listen Exotica Catalog." For the truly interested, there are even .csv files on the Exotica Catalogue Website containing a massive quantity of data related to the location of solar system objects, useful appendices, and more. The whole thing is, frankly, a jaw-droppingly detailed work of Herculean effort. 

In the end, the Exotica Catalog breaks down the search for extraterrestrial life into four sections: Prototype, Superlative, Anomaly, and Control. The Prototype section, the largest of the four, details "every known major type of non-transient celestial object," except those that are too fleeting to warrant mention, as Vice says. The Superlative section describes extreme phenomena that serve as outliers in data sets. We're talking the biggest energy signature, hottest star, fastest-spinning planet, and things like that.

The Anomaly section measures one-offs that we can't completely explain, or have sparked interest in the debate for extraterrestrial life. Examples include evidence for the aforementioned star-enclosing Dyson sphere, or the 'Oumuamua, the cigar-shaped rock that putzed through our solar system in 2017. Finally, the Control section includes what could be called "false positives": Occurrences once believed to relate to alien life, but actually don't. This can help us avoid similarly incorrect conclusions in the future.