The simplest explanation is that it is a technology designed by an alien being

Astronomers: A creature from outside the planet visited us in 2017

The traveler landed in a strange way and was unusually luminous, indicating that it was made of shiny metal.

archival

In October 2017, astronomers noticed an object moving so fast that it could only have come from another star, the first recorded instance of an interstellar intruder.

It did not appear to be an ordinary rock, for after it set off around the sun it accelerated and veered from the expected course, driven by a mysterious force.

This could easily be explained if a comet was expelling gas and debris, but there was no visible evidence of this "gassing" process.

The traveler also landed in a strange way, in the manner that made it brighter and fainter in scientists' telescopes, and was unusually luminous, indicating that it was made of shiny metal.

In order to explain what happened, astronomers had to come up with new theories, such as that it is made of hydrogen ice and therefore has no visible traces, or that it dissolves into a dust cloud.

Thus begins a new book by a prominent astronomer who argues that the simplest and best explanation for the unusual properties of an interstellar object that passed through our solar system in 2017, was that it was technology designed by an alien.

Does it seem strange?

Scientist Avi Loeb says, "The evidence proves otherwise, and he is convinced that his peers in the scientific community are so immersed in groupthink that they are not willing to resort to Occam's blade (a way of thinking, analyzing and deducing simple without diving into complexities)".

Loeb, who was longtime chair of astronomy at Harvard University, published hundreds of groundbreaking papers, and collaborated with greats like the late Stephen Hawking, is hard to dismiss.

The scientist believes that "the idea that we are unique and special is arrogance."

"The right approach is to be humble and say, 'We are not special, there are a lot of other cultures, we just need to find them,'" he said.

"These ideas that have always come up to explain Oumuamua's characteristics don't include something we haven't seen before," Loeb said.

"If that's the direction we're taking, why don't we think it's synthetic in origin?" he added.

Oumuamua was not photographed up close during his short stay, as his existence was discovered as soon as it left our solar system.

There are two forms that match the distinct characteristics observed.

Long and thin like a cigar, or flat and round like a pancake.

But Loeb points out that simulations lean toward the latter, and he believes the object was intentionally made in the shape of a sail propelled by stellar radiation.

It was also surprising the way the object moved, which made its passage even more strange.

Before colliding with our sun, Oumuamua was "at rest" compared to its neighboring stars, which is a rarity.

Rather than thinking of it as a ship scurrying through space, from the perspective of its shape, our solar system hit it.

But Loeb's ideas put him at odds with his peers.

Astrophysicist Ethan Segel described him in Forbes magazine as a "once respected scientist", but he failed to convince his peers of his arguments, so he began trying to persuade the public.

Loeb, for his part, is protesting the academy's "bullying culture" that punishes people who question orthodoxy, just as Galileo was punished for suggesting that the Earth is not the center of the universe.

• Flat and round like a pancake, as scientist Avi Loeb believes.

Follow our latest local and sports news and the latest political and economic developments via Google news