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Is ‘Oumuamua an alien Lightsail spacecraft?

‘Oumuamua that strange cigar-shaped object that visited us from deep interstellar space earlier this year. Most conclusions were made that it was a comet because scientists measured a mass-loss rate coming from ‘Oumuamua meaning there was a tail, even if it wasn’t visible. However new speculations point to the possibility of ‘Oumuamua being an alien spacecraft.

This artist’s impression of `Oumuamua, discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii. Observations from ESO’s Very Large Telescope in Chile show that ‘Oumuamua was traveling through space for millions of years before it entered our star system. `Oumuamua seems to be a dark red highly-elongated metallic or rocky object, about 400 meters long, and is unlike anything normally found in the Solar System.

This is one of the first objects observed to have come from interstellar space, meaning outside our solar system! So because o this there are a lot of assumptions being made. But– let’s get down to the SCIENCE of why some believe ‘Oumuamua to be extraterrestrial sent.

‘Oumuamua was being tracked; it’s trajectory, velocity, mass-loss rate, etc. Scientists measured that when ‘Oumuamua passed by the Sun it’s velocity increased and ‘Oumuamua accelerated as it zipped past the Sun.  This is similar to how a lightsail spacecraft would gain acceleration from using the energy transmitted from the Sun to fuel the spacecraft.


What are the possibilities that ‘Oumuamua came from aliens? For this we have to look at the Drake equation. The Drake equation looks at the possibility for intelligent life to exist in our Milky Way galaxy. Because if ‘Omuamua is an alien lightsail the aliens that sent it have to be a relatively intelligent species with advance-enough technology to develop this. We here on Earth have developed lightsail spacecraft before, just look at the Planetary Society as an example.


There’s 100 billion stars in the Milky Way Galaxy. 2 trillion galaxies in the universe. There’s roughly 2*10^23 stars in the universe. 1 in every 6 has an Earth sized planet. 3.2*10^22 stars in the universe that likely host an Earth-like planet. What we mean by Earth-like planet is a planet with terrestrial properties, similar size and composition to Earth, and in the habitable-zone or “goldilocks-zone.” This is the region around a star where the planets are not too close and not too far from the Sun, where the conditions are “just right” for a basic atmosphere to form, and possibly life.

So whether ‘Oumuamua was alien-sent or is a cluster of space-debris, a comet or asteroid, it’s still the first object we observed that came from outside our solar system and it’s really cool. It is now on it’s journey out moving at 26.33 km/s (94,800 km/h).  Bye bye ‘Oumuamua (which means messenger or scout in Hawaiian btw!).