“It is in the admission of ignorance and the admission of uncertainty that there is a hope for the continuous motion of human beings in some direction that doesn’t get confined, permanently blocked, as it has so many times before in various periods in the history of man.”
Richard P. Feynman
When studying about the most notable scientific stories of the XXIst century, future students will probably giggle when trying to memorize a peculiar word found in their books: Oumuamua.
Recognized as the first object of unquestionable interstellar origin to ever intrude into our solar system –we know this because of the highly eccentric orbit it displayed in contrast to the ecliptic plane that most bodies in the system follow when orbiting around the Sun– Oumuamua was discovered in October of 2017 by Robert Weryk at the Haleakala Observatory in Hawaii, and ever since it has continued to puzzle scientists because its shape and behavior was even weirder than the name it was assigned to (it means “first distant messenger” in Hawaiian).
Oumuamua moved like a comet, and yet it didn’t produce the characteristic tail of these icy bodies. To make things even more confusing, the varying light emitted by this not-comet suggested Oumuamua was at least 10 times as long as it was thick. How could this ‘interstellar baton’ retain its fragile form for so long?
And then there was the final insult to our knowledge about errant astronomical bodies, observed in June of last year: new data from the Hubble telescope confirmed Oumuamua’s velocity had increased during its rendezvous with the inner solar system, in ways that could not be explained by simple celestial mechanics and gravitational influences.
Astronomers paused their collective hand from scratching their collective head only to make that hand into an angry fist when they read a truly bold and controversial paper co-written in November of last year by Abraham Loeb, chairman of Harvard University’s astronomy department, and his postdoctoral student Shmuel Bialy. The paper was very rigorous in its math and the scientific assertions it proposed, and at the same time it did something no-one else in the scientific community dared to do: Suggest Oumuamua was in fact an ancient solar sail built by an extraterrestrial civilization and deliberately sent to intercept our solar neighborhood.
Last week the Israeli newspaper Haaretz published an excellent interview with Loeb, which not only helps to explain in layman terms why Oumuamua is a true anomaly, but also highlights the many problems arising from the way the academic community tends to behave when confronted by a scientific mystery: with an a-priori contempt for any kind of novel ideas, especially when it comes to the possibility about alien life. An arrogant ‘it can’t be therefore it isn’t’ attitude that is even more prevalent –ironically enough– among the scientists more directly involved with the search for extraterrestrial intelligence (SETI). It’s almost as if we are so certain there’s no one else out there, we keep on looking for signs we’re not alone without really expecting to find any.
Not only that, but Loeb points out the kind of fear prevalent among his colleagues of making their ideas public, if they happen to be too ‘heretical’:
“The article I published was written, in part, on the basis of conversations I had with colleagues whom I respect scientifically. Scientists of senior status said themselves that this object was peculiar but were apprehensive about making their thoughts public. I don’t understand that. After all, academic tenure is intended to give scientists the freedom to take risks without having to worry about their jobs. Unfortunately, most scientists achieve tenure – and go on tending to their image. As children we ask ourselves about the world, we allow ourselves to err. Ego doesn’t play a part. We learn about the world with innocence and honesty. As a scientist, you’re supposed to enjoy the privilege of being able to continue your childhood. Not to worry about the ego, but about uncovering the truth. Especially after you get tenure.”
In the interview, Loeb explains to the Haaretz reporter that Oumuamua is probably shaped like a flat pancake instead of a cigar. Not only that, but its relative velocity compared to the average speed of all the stars in the region suggests this ‘distant messenger’ was at ‘relative rest’ until the solar system reached its position while traveling around the center of the Milky Way. Read that last sentence again until it sinks in.
But how to explain the biggest mystery of all –Oumuamua’s sudden and inexplicable acceleration once it entered the inner solar system? “The only hypothesis I could think of,” Loeb says, “is a push from solar radiation pressure. For that to work, the object would have to be very thin, less than a millimeter thick, in other words a type of pancake. In addition, the Spitzer Space Telescope found no evidence of heat emission from the object, and that means that it is at least 10 times more reflective than a typical comet or asteroid. What we have, then, is a thin, flat, shiny object. So I arrived at the idea of a solar sail: A solar sail is a spaceship that uses the sun for propulsion. Instead of using fuel, it is propelled ahead by reflecting light. In fact, it’s a technology that our civilization is developing at this very time.”
I urge you to read the interview in its entirety. In the end, I feel whether Loeb is correct or not about Oumuamua, and it was not in fact an ancient probe sent by an advanced civilization tens of thousands of years ago, is not the most important thing about the paper he and his student wrote. As the scientific director of Project Starshot which studied the possibility of deploying solar sails traveling at one-fifth the speed of light, critics could very well argue he’s falling into an ‘anthropomorphization’ of this astronomical anomaly, attributing aliens with the same kind of technology we’re currently trying to develop –then again, SETI is also guilty of the exact same thing, insisting our hypothetical galactic neighbors would only bother to communicate with us using radio transmissions.
No, the value in Loeb’s hypothesis is that it helped to highlight how in the cutting-edge areas of Science, we tend to punish innovative thinking instead of encouraging it. Scientists are being conditioned to stick to what is accepted by the status quo in order to protect their careers. Only the older scientists who are sufficiently shielded from professional suicide by having already achieved enough recognition, or won enough prizes and medals, are the ones brave enough to dare to say “what if” out loud. With that kind of rationale, we are less likely to make any major breakthroughs.
“If you’re not ready to find exceptional things, you won’t discover them. Of course, every argument needs to be based on evidence, but if the evidence points to an anomaly, we need to talk about an anomaly. Who cares if this anomaly appeared or did not appear in science-fiction books? I don’t even like science fiction.”
Loeb’s colleagues are still detecting mysterious fast radio bursts (FRBs) coming from the deepest reaches of the Universe. Nobody knows what originates them, but suggesting they could be actual transmissions of artificial origin is not considered kosher among ‘serious’ researchers. Likewise, NASA is getting prepared to probe the surface of Mars in search of microbial fossils, and yet the debate involving meteorite ALH 84001, discovered in Antarctica more than 20 years ago, rages on. The findings of the scientists who suggested the microscopic structures found inside the meteorite were signs of Martian life were flat-out rejected by most of the scientific community –this at a time when even considering the possibility that Mars had had water in its ancient past was simply preposterous.
Perhaps schools should teach the future generations of scientists and thinkers to dare to be wrong more often. Instead of waiting ’til they get tenure and secure retirement.