Our first-ever interstellar visitor has been sighted

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It appears to be a dark red, highly-elongated metallic or rocky object, about 1,312 feet (400 m) long. The authors of the study describing 'Oumuamua write that "immanent upgrades to contemporary asteroid survey instruments and improved data processing techniques are likely to produce more interstellar objects in the upcoming years". Image credit: M. Kornmesser / ESO. It initially looked like a typical fast-moving small asteroid, but additional observations over the next couple of days allowed its orbit to be computed fairly accurately.

That odd shape is unprecedented among the some 750,000 asteroids and comets observed in our solar system where they formed, said the researchers. "This serendipitous discovery is bonus science enabled by NASA's efforts to find, track and characterize near-Earth objects that could potentially pose a threat to our planet".

Observations from large ground-based telescopes will continue until the object becomes too faint to be detected, sometime after mid-December.

It was at that point that the larger telescopes like the VLT in Chile were powered up and brought into the search.

"We had to act quickly".

The team had to be quick as Oumuamua had already passed its closest point to the Sun and was heading out of our solar system back into deep space at an alarming rate. Here we report observations and subsequent analysis of 1I/2017 U1 ('Oumuamua) that demonstrate the extrasolar trajectory of 'Oumuamua.

The mystery object, known as A/2017 U1, was discovered in October by a researcher using a sophisticated telescope system at the University of Hawaii that continually scans the universe for such phenomenon.

The asteroid is spinning on its axis every seven hours and experts are unsure where it is going to head next. They figured out that the most logical explanation was that the asteroid is about ten times longer (ten times more reflective area) than it is wide.

These properties suggest that 'Oumuamua is dense, composed of rock and possibly metals, has no water or ice, and that its surface was reddened due to the effects of irradiation from cosmic rays over hundreds of millions of years.

"We also found that it had a reddish colour, similar to objects in the outer solar system, and confirmed that it is completely inert, without the faintest hint of dust around it", Meech added. Apparently, this asteroid is long and skinny, much like a cigar, and is spinning constantly as it travels, as if some otherworldly explosion or cataclysmic event picked up the little rock and tossed it out across the galaxy like a very big throwing knife.

"While study of 'Oumuamua's colors shows that this body shares characteristics with both Kuiper Belt objects and organic-rich comets and trojan asteroids, its orbital path says it comes from far beyond", Dr. Meech said.

Preliminary calculations suggest that it may have come from the bright star Vega within the constellation of Lyra. "The first-ever detected interstellar traveler, now named "'Oumuamua," turns out to be different from any object seen before and has been roaming between the stars for hundreds of millions of years.