Solar system may be ‘teeming with alien tech’

Fleeting glimpse: Oumuamua is heading away from us at 30 kms per second. © ESO

Are scientists refusing to face the truth about aliens? A top astronomer believes a strange object over Hawaii was an extraterrestrial craft – but claims his colleagues prefer not to know.

Trawling the skies on 19 October 2017, the world’s most powerful telescope captured an extraordinary image. Pan-STARRS1, situated in Hawaii, detected a thin, flat object the size of a football pitch moving away from the sun. It did so with a strange tumbling motion, turning end over end every seven hours, varying in brightness as it did so.

For the 11 days that it was visible, astronomers were mystified. Most concluded that it was a strange type of asteroid or comet, being turned over – as such objects often are – by jets of evaporating gas on its surface. The only problem was that these jets usually appear as a visible tail. And this time, there was no tail to be seen. The team that had spotted it named it Oumuamua – Hawaiian for “first scout from a distant place”.

For one man, this name had a particular significance. Avi Loeb was convinced that the object had entered our solar system from interstellar space for a purpose.

Loeb is one of the world’s most distinguished astronomers. He was a leading figure in the Event Horizon Telescope project, which produced the first photograph of a black hole. He has helped develop new ways of detecting exoplanets, and correctly predicted the existence of stars that shoot between galaxies at almost half a billion miles an hour.

In November 2018, Loeb and his research assistant Shmuel Bialy published an article in the magazine Astrophysical Journal Letters which caused a sensation. His argument – developed in a new book called Extraterrestrial: The First Sign of Intelligent Life Beyond Earth – was that Oumuamua was something humans had never seen before.

Instead, it was “a new class of thin interstellar material, either produced naturally, through a yet unknown process… or of an artificial origin”. Loeb believed that it was the latter: in other words, a piece of alien technology.

His theory was partly based on Oumuamua’s movement, or lack of it, in relation to the solar system. It appeared to be positioned like a buoy in the ocean, with the sun moving past it and bumping it with its gravitational field.

Even more significant was its highly unusual shape and lack of a comet’s tail. Comets also move jerkily, whereas Oumuamua’s motion was smooth.

Loeb was understandably disappointed when most of the scientific community rejected his theory. But what worried him more, he says, was a wider problem: their refusal to engage with the idea of alien intelligence at all.

He cites a remark by a colleague at Harvard University: “This object is so weird – I wish it never existed.” It was, Loeb insists, “a terrible thing to say for a scientist… you should accept with open arms anything that nature gives you”.

The question, he says, is whether humans are ready to confront the idea that life on Earth is not unique, and not even particularly impressive. “I fear the answer is no,” he writes in his book, “and that prevailing prejudice is a cause for concern”.

Are scientists refusing to face the truth about aliens?

Galactic perplexity

Some say, yes. When someone as distinguished as Avi Loeb believes aliens could exist, his colleagues should certainly investigate the possibility. The only other object that has been seen to behave in the same way as Oumuamua turned out to be the remains of a US rocket. So it is logical to suppose that Oumuamua too was manufactured rather than created naturally.

Others argue that we are constantly discovering new things about the universe, and just because we have not encountered something like Oumuamua before, we should not deduce that aliens made it. If it were a spacecraft, you would expect it to produce some kind of noise, but radio astronomers who trained their antennae on Oumuamua failed to pick anything up.

You Decide

  1. If you knew that the universe contained a more intelligent species than us, how would that affect your view of the world?
  2. Loeb argues that while we cannot be sure that aliens exist, science can only benefit from assuming that they do. Do you agree?


  1. In Douglas Adams’s The Hitchhiker’s Guide to the Galaxy, Earth is demolished to make way for an intergalactic bypass. Design 10 road signs for spacecraft using it.
  2. Imagine that you are an alien inspecting Earth from Oumuamua. Write a report giving your impressions of the planet.

Some People Say...

“The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.”

Isaac Asimov (1920 - 1992), American science-fiction author

What do you think?

Q & A

What do we know?
It is generally agreed that the astronomical theory that faced the greatest opposition was heliocentrism. This argued that the Earth moved round the Sun, rather than the other way round, as was generally believed. Copernicus, who developed it in the 16th Century, did not dare publish his findings. They were condemned by the Roman Catholic Church after his death, and when Galileo supported them, he was put under house arrest for the remainder of his life.
What do we not know?
One main area of debate is around how many more Oumuamuas there might be out there. Loeb argues that since Pan-STARRS found one after four years of observation, we can assume that it will find another by the end of this year – and a more powerful telescope being set up in Chile could find one a month. Altogether, he believes, there are “plenty of them, a quadrillion of them” in our solar system.

Word Watch

An abbreviation of Panoramic Survey Telescope and Rapid Response System.
Situated in the Pacific Ocean, it is the only island state in the US, which it joined in 1959.
Also known as minor planets or planetoids, asteroids are made up of rock and minerals. The majority of known ones orbit the Sun between Mars and Jupiter.
Consisting mainly of dust, ice and gas, comets also orbit the Sun, with tails that can be millions of miles long.
Event Horizon Telescope
A worldwide network of radio telescopes set up in 2009 specifically to investigate black holes.
Planets that orbit stars other than the Sun.
The area of space beyond the Sun’s magnetic field. The point at which it begins is known as the heliopause.
The second one of two things or people that have been mentioned. Here, it refers to the material of “artificial origin”.
Plural of antenna, a metallic rod or wire used for sending or receiving radio waves.


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