are we alone? This is perhaps the deepest question that still faces humanity today. What if the answer to this question is no? Will we be ready to accept it? For Avi Loeb, an astrophysicist at Harvard University (United States), the extraterrestrial technique has recently crossed our solar system. He explains to us how he came to this conclusion.
October 2017. Reports sighting of an observatory in Hawaii (United States)That across us To one About four times . The object follows a hyperbolic trajectory that indicates It comes from elsewhere. Its baptism is 1I / 2017 U1. And quickly nicknamed ‘ , Understand “Guest”, “messenger”. It arouses all curiosities. “Oumuamua amazes scientists”, Then title . Because it’s so long ago Close to the Earth is also celebrated. But also because it surprisingly presents a certain number of surprising features.
Comets, asteroids, pieces of celestial bodies. For months, all beliefs about its nature have been placed on the table. Including the craziest of all: the alien ship! Endorsed a hypothesis – by Abraham Loeb, chairman of the Department of Astronomy at Harvard University (United States) – against and against almost all. ”Encourages caution. We make a hypothesis, gather evidence and test that hypothesis. We then refine the hypothesis or gather more evidence. But fashion can discourage the idea of certain beliefs and careerism can direct attention and resources towards certain subjects and distance them from others. “, He explains.
“Personally, I believe that Oumuamua is proof that there are or areOther than us . And I would like the community to agree to give my theory as much credit as they give to the hypothesis Or multiverse. But I also believe that humanity is not willing to believe that we are not unique. “
Oumuamua, a strangely shaped interstitial object
But on what basis does AV Loeb base his hypothesis? On some of the singularities noted by researchers studying the interstellar object. Its shape first. “We have no clear image of the object. Data from observation of only eleven days – Before the object goes too far away from the Earth – By many telescopesSays Avi Loeb. They show that shineVaries by a factor of ten every eight hours. “ What concludes is that the object is longer than it is wide. Some previously spoke of cigar size. Then transferred the data, statistically much more likely, to some form of disk.
“Anyway, we have never seen in nature, such a flat and / or elongated objectAssures us Avi Loeb. And this does not refer to the fact that ‘Oumuamua was also at least ten times faster than any asteroid orSame size. “ Several explanations have been put forward.
This animation depicts the journey of the 1I / 2017 interstellar object U1, aka ‘Oumuamua’, through our solar system. Following a trajectory that surprised astronomers. © European Southern Observatory
A trajectory that defies the laws of physics
“If only this had happened, I would have gone ahead”Says Avi Loeb. But there was alsoThe trajectory that appears in the data collected by astronomers. According to a Harvard University researcher, this is « Breathtaking ». Law of Allow us to predict the trajectory of an object Of . But expected Oumuamua did not behave as expected. “ Remote from us , He pushed himself by a mysterious force. “It also happens for comets. One type of “rocket engine” effect is that they are due to their long tail of evaporated ice. “
To this effectExplaining the deviation of the trajectory of ‘Oumuamua’, the object would have lost one-tenth of it . However, by scanning the surrounding location, astronomers found no trace of water, Or dust.
Other hypotheses have been put forward. The first, which collides with another object. But the data did not match. Then the iceWas specially composed . But this idea did not last long. Acted upon Radiation from the Sun was also investigated. But it would involve an incredibly low mass density. Only 1% of On the surface of the Earth. This is enough to make Oumuamua the most porous object ever in our solar system.
‘Oumuamua, a foreign vessel?
“To me, ‘Oumuamua is unlike anything in the universe that we know would have been designed, built and launchedSupernatural. Perhaps a veil is floating in space. A communication buoy. Or a piece of debris left by a civilization other than ours, Avi Avi Loeb. I know it’s a hypothesis . But other hypotheses have been put forward to explain these special features, which are no longer deficient. No one can really explain the trajectory of ‘Oumuamua’. And yet, the object went astray “Do not hesitate to launch the researcher in the eyelid On .
“Be it, let’s be clear. I’m not one of the fansOf . I’m not “nervous about Astroturf”. I am just asking myself questions. By trying not to let myself get overwhelmed by prejudices. “