When the first sign of intelligent life first visits us from space, it will not be a giant saucer hovering over New York. More likely, it will be a foreign civilization’s trash can.
Avi Loeb, the chairman of Harvard’s astronomy department, believes he has already found some of the rubbish.
In his forthcoming book “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” (Houghton Mifflin Harcourt), on January 26, the professor raises a compelling case as to why an object that has recently wandered around in our solar system is not just another ‘ another was not. rock, but actually a piece of alien technology.
The object in question traveled from the direction of Vega, a nearby star 25 light-years away, to our solar system and on 6 September 2017 intercepted the orbital plane of our solar system.
On September 9, the orbit brought it closest to the sun. At the end of September, it blew about 58,900 miles per hour past Venus’ orbital distance, and then, on October 7, it shot past Earth before “moving rapidly toward the constellation Pegasus and the blackness beyond,” Loeb writes. the book.
The object was first spotted by an observatory in Hawaii with the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) – the highest definition telescope on earth.
The space object called the name ‘Oumuamua’ (pronounced ‘o moo ah moo ah’), which is Hawaiian for – roughly – ‘explorer’.
As far as astronauts go, it was relatively small, only about 100 meters long, but it was a big issue in the scientific community.
To begin with, it was the first interstellar object ever detected in our solar system. Judging by the trajectory of the object, astronomers concluded that it was not bound to the gravitational pull of the sun – suggesting that it was just passing through.
No sharp photos could be taken, but astronomers were able to practice their telescopes on the object for 11 days, and they collected other data.
Initially, scientists thought it was an ordinary comet. But Loeb said the assumption carries the risk that ‘the celebrities could define what we would discover’.
“What happens if a caveman sees a cell phone?” he asked. “He had seen rocks all his life, and he would have thought it was just a shiny rock.”
Loeb soon opened his mind to another possibility: it was not a comet, but the technology of a strange civilization thrown away.
A number of unusual properties of the object helped Loeb to draw this conclusion.
First was’ Oumuamua’s dimensions.
Astronomers watched the object reflect sunlight. Its brightness varied tenfold every eight hours, indicating that this was the amount of time it took to complete a full revolution.
Scientists have concluded that the object was at least five to ten times longer than it was wide – like the shape of a cigar.
No natural space body we have ever seen looked like – or even close to.
“This will make the geometry of Oumuamua at least a few times more extreme in aspect ratio (or width to height) than the most extreme asteroids or comets we have ever seen,” Loeb writes in his book.
What’s more, ‘Oumuamua was extraordinarily bright. It was at least ten times more reflective than a typical solar system [stony] asteroids or comets, ”the author writes.
He compares its surface to shiny metal.
But the deviation that really drove Loeb to his ET hypothesis was the way ‘Oumuamua’s moved.
“The excess pressure from the sun – that was the thing that broke the camel’s back,” he said.
Using physics, scientists can calculate the orbit that an object should take and what velocity it should move due to the gravitational force that the sun exerts. The pull of the sun will massively accelerate an object as it approaches, and then kick out on the other side, so that the object becomes significantly slower as it moves further away.
But ‘Oumuamua did not follow this calculated path. The object actually ‘accelerated’ slightly, but to a very statistically significant extent, ‘Loeb writes as it moves away from the sun.
In other words, it is clearly only pushed by the sun’s gravity by a force.
At first, the explanation seemed simple. Comets show a similar acceleration, because as they approach the sun, their surface becomes hot and releases one-time frozen gases, which act like a rocket engine.
However, the released materials form the characteristic tail of a comet. Scientists looked closely at that tail or any sign of gases or dust that could be driving Oumuamua and came up empty.
Loeb calculated that the chance that ‘Oumuamua was a random comet, at these and other deviations, was about one in a quadrillion, which led him to his hypothesis.
But what exactly was it?
Oddly enough, one possibility can be found in technology we already have here on earth.
“Some people do not want to discuss the possibility that there are other civilizations.”
Avi Loeb, Harvard astronomer and author of “Extraterrestrial”
About 400 years ago, astronomer Johannes Kepler observed comet tails that looked like a solar eclipse and wondered if the same power could propel rocket ships through space as the wind pushes boats through water.
It was a clever idea that scientists are now using to develop light sails for sin. Thin, reflective slices are folded open in space to trap the particles flowing from the sun and propel a ship at high speed through the empty void. Alternatively, powerful lasers can be aimed at the sail from the ground to make it go faster.
Loeb, who is involved in a light sailing project to send a small, unmanned vessel to a star in the area, said that if strangers thought of this idea, why would strangers not?
He and a colleague snapped the numbers and assumed that ‘Oumuamua was not actually cigar-shaped, but possibly a disk less than a millimeter thick, with sail-like ratios that would explain the unusual acceleration as it moved away from the sun.
As for his goal, Loeb is not entirely sure. He speculated that it could be ‘space junk’ that once served as a kind of spatial navigation buoy used by a long-ago civilization.
‘The only way to search [alien civilizations] is to search for their trash, like investigative journalists looking through the person’s trash, ”Loeb said.
Of course, not everyone in the scientific community agrees with his theory.
In July 2019, the ‘Oumuamua team from the International Space Science Institute published an article in Nature Astronomy and concluded:’ We find no compelling evidence to favor a strange statement for ‘Oumuamua.’
Loeb acknowledges that his theories have raised astronomers’ eyebrows, but he is adamant about his findings. “Some people do not want to discuss the possibility that there are other civilizations,” he told The Post. “They believe we are special and unique. I think this is a prejudice that needs to be abandoned. ”
Loeb said the skeptics bend over backwards to attribute the original natural origin, and that the explanations they gave to explain its strange properties could not fit.
For example, some scientists have suggested that ‘Oumuamua’s acceleration was caused by frozen hydrogen on the surface that changed to gas and propelled it like a comet, and that hydrogen would be invisible to Earth’s infrared cameras, so we did not have it. not detected.
But Loeb and a colleague published an article showing that a hydrogen iceberg moving through interstellar space will evaporate before it reaches our solar system. ‘
Whatever the truth, the income is high.
The assumption that an alien race made contact – even through its rubbish – would cause a serious search for more garbage, which would make us search for the moon and Mars, for example for rubbish that could have crashed thousands or millions of years ago. .
And if more evidence is found, our earthlings will have to start building tools to help us with extraterrestrial paths, such as space treaties and academic fields such as astro-linguistics and astroeconomics.
But, perhaps more importantly, any further discoveries can redefine our place in the universe.
“It will put us in perspective,” Loeb said. ‘If we’m not alone, are we the smartest kids in the block? If there was a species that changed itself through war or through climate, we could get along and act better. Instead, we waste a lot of resources on Earth fighting each other and other negative things that are a huge waste. ”
Since ‘Oumuamua’s appearance, a second interstellar object known as 2I / Borisov was spotted in 2019 by a Crimean telescope in the solar system. But it turns out to be an ordinary old comet.
Until recently, our tools were not sensitive enough to charge such visitors. But Loeb said technology will soon make it possible to track down more space travelers, and the only way the mystery of ‘Oumuamua’s will be solved is if a similar object is spotted and investigated more thoroughly with a probe.
He said his book “should motivate people to gather more data on the next object that looks strange.”
“If we find another and we take a picture and it looks like a light sail, I don’t think anyone will argue with that.”