Well we all know a lot about space but what is Oumuamua?

Oumuamua was the first known interstellar object that was detected passing solar system. It was discovered by Robert Weryk using Pan-STARRS1 telescope at University of Hawaii’s on Oct. 19, 2017. It was discovered more or less 40 days after it passes its closest point to the sun on September 9.

It appears to be rocky, cigar shaped object with reddish hue. It is estimated to be about 1,300 to 2,600 feet. Originally it was classified as comet C/2017 U1, but later reclassified as asteroid A/2017 U1 due to the absence of a coma. Oumuamua varies in brightness by a factor of 10 as it spins on its axis every 7.3 hours and also has a light curve amplitude of 2.5 magnitudes. It has a radius of about 200 m. It is estimated to be 10 times as long as it was width. However ʻOumuamua’s planetary system of origin and the age of its excursion are unknown.

As soon as it grabbed attention two things in particular fixated scientists. The first was its acceleration away from sun which was hard to resonate with many ideas. The second one was its peculiar shape.


 It was initially named 1I/2017 by the International Astronomical Union (IAU), which was responsible for granting official names. But later  Pan-STARRS team dubbed it to Oumuamua, which in Hawaiian means “a messenger from afar arriving first”. It is pronounced as oh MOO-uh MOO-uh.


Astronomers were able to record its data only for a short period of time even though its been in our solar system for over decade. Oumuamua wasn’t spotted for a long time because it was too far from the Sun to reflect enough light for astronomers to pick it up. Once it got close enough to the Sun, it was moving fast, remaining for very little time in the relatively small region where it was visible to modern-day telescopes. Oumuamua was again on its way out. “Our very last observations from Hubble were January 2nd of 2018 at fainter than magnitude 27”, says Meech “By May 3rd, it was again outside of Jupiter’s orbit. And once it gets beyond about 1.2 AU or so, it’s 25th magnitude, so beyond Jupiter’s orbit, forget it. It’s gone”, he added. According to Meech, Oumuamua is expected to reach the Kuiper belt in about 2024, and pass the edge of the Kuiper belt in late 2025. It will pass the most distant location the Voyagers have reached, she says, in about 2038. By 2196, it will again be 1,000 AU from the Sun, although our Oort Cloud is projected to extend beyond 100,000 AU, so when Oumuamua truly passes the “edge” of the solar system depends on where you define that edge. Regardless, since January, ‘Oumuamua has been beyond astronomer’s reach.


Some astronomers even suggested that ʻOumuamua could be a product of alien technology. However evidences are not too strong. Therefore the alien object hypothesis is considered unlikely by many experts.

Apart from this, Borisov is another interstellar object that was found August 30.

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