There could be 4 quintillion alien spacecraft buzzing through our solar system
Five years ago, a very strange object – perhaps a thousand feet long, oblong, shiny and fast – streaked through space, tens of millions of miles from Earth. Its course and speed indicated that it came from outside the solar system. A visitor from another star.
Astronomers have dubbed the thing ‘Oumuamua– Hawaiian for “scout” – and started arguing about it.
On the one hand, there is an overwhelming majority of scientists who do not know what ‘Oumuamua is, but are unwilling to speculate on what it is. strength be.
On the other side is a much smaller camp led by Harvard astronomer Avi Loeb, who argues that we should at least consider the possibility that ‘Oumuamua is an alien spaceship.
Loeb now asks the next logical question. How many more ‘Oumuamua could there be in and around the solar system? In a new study which appeared online Sept. 22 and has yet to be peer-reviewed, Loeb and co-author Carson Ezell, also a Harvard astronomer, concluded there were as many as 4,000,000,000,000 000,000 (or 4 quintillion).
Each is a visitor from another star, and each, perhaps, artificially created.
That may seem like a lot. But the solar system is vast. And the space between our star system and our nearest neighbor, Proxima Centauri, is even larger. In fact, finding one of these 4 quintillion possible mystery objects for further study could be really, really difficult.
To be clear, Loeb is not claiming that there are quintillions of extraterrestrial craft orbiting our corner of the Milky Way. After all, he never said ‘Oumuamua is definitely a robotic probe or a manned craft – just that we should be open to the possibility.
So what Loeb and Ezell calculated is not the alien craft population. It is the population of possible extraterrestrial or other craft possible artificial objects. Remnants of ET rocket parts. Unexplainable fragments of extraterrestrial technology beyond our comprehension. That sort of thing.
The calculation is simple. “One can use recent interstellar object detection rates and known capabilities to estimate the density of similar objects in the solar neighborhood,” Loeb and Ezell wrote.
They started with all the objects that astronomers have detected that have come from outside the solar system. These are objects that, in other words, could come from an extraterrestrial civilization or nearby, just beyond the sight of our probes and telescopes.
There are four: ‘Oumuamua, of course, but also the interstellar meteors CNEOS 2014-01-08 and CNEOS 2017-03-09, plus the interstellar comet Borisov.
That’s four interstellar visitors in eight years. Loeb and Ezell took into account how much of a galaxy we can observe with our instruments – which isn’t much – in order to arrive at an estimate of how many more objects like ‘Oumuamua might be out there in darkness, having arrived from a nearby star system.
They actually found two numbers. One for all interstellar objects, including those that move randomly around and through the solar system and are not likely to pass within sight of our instruments. That’s a staggering 40,000,000,000,000,000,000,000,000,000,000,000 (or 40 decillions).
The lower number, 4 quintillion, is for objects that appear to be directed toward the “habitable zone” of the solar system, close to the sun. This is where Earth orbits and where astronomers have a chance of spotting a passing object.
That lower number is the most exciting, and not just because closer objects are much easier to detect. They are also the objects most likely to be extraterrestrial craft. After all, they seem to be aiming in our direction. They are objects with a purpose.
But even Loeb does not propose that there are 4 quintillion objects exactly like ‘Oumuamua. This object is remarkable not only for its apparent origin, but also for its size. It is large enough to be a very large crewed spaceship. Judging by the interstellar comets we have detected, there is a good chance that more interstellar objects in the habitable zone around the Sun are tiny, probably no larger than 3 feet in diameter. There are probably a million of these for every Oumuamua-sized object, Loeb explained.
That still leaves a lot of potential ‘Oumuamuas out there somewhere in the habitable zone of the solar system. Each a possible alien craft, if you share Loeb’s open-mindedness.
But actually locating these objects, let alone inspecting them closely, is extremely difficult. It’s so difficult that a close encounter with a passing alien craft is the least likely way we’ll get. make first contact with extraterrestrialsaccording to Edward Schwieterman, an astrobiologist at the University of California, Riverside.
“In my opinion, we are much more likely to detect life that originates outside our solar system through remote observation than through physical encounters,” Schwieterman told The Daily Beast.
We were lucky with ‘Oumuamua. It’s really big, really bright, and it passed about 21 million kilometers from Earth.
But the solar system is more than 9 billion kilometers in diameter. And it’s another 20 trillion miles to Proxima Centauri. Small and very distant, most interstellar objects, even those that pass through the habitable zone, will be much harder to find than ‘Oumuamua. “Space debris is hard to see from afar,” Seth Shostak, a California-based SETI Institute astronomer, told The Daily Beast.
We are improving though. New telescopes, including NASA’s James Webb Space Telescope, are helping us peer further into the darkness of the outer solar system, find smaller and smaller objects, and separate local features from potential interstellar visitors.
Loeb also pointed to the Vera C. Rubin Observatory which is under construction in Chile. Scheduled to open in 2023, the observatory with its 3.2 billion pixel camera should be able to study the entire southern sky every four days. “A high-resolution image could reveal bolts and screws on the surface of a man-made object and distinguish it from a nitrogen iceberg, a hydrogen iceberg, or a dust bunny,” Loeb said. .
‘Oumuamua was a missed opportunity. Sure, Loeb is open to the idea that it’s an alien probe, but most astronomers aren’t. If we can take a closer look Next ‘Oumuamua, maybe more scientists will come to the idea that it could be an extraterrestrial craft.
In theory, we have 4 quintillion opportunities.