Interstellar object seen in solar system for first time

Astronomers around the world have rushed to observe the first confirmed interstellar object in our solar system, taking the form of a cigar-shaped asteroid.

The object, dubbed ‘Oumuamua (Hawaiian for “messenger from afar, arriving first”), measures up to 400 metres long and could be up to ten times longer than it is wide, NASA wrote on its website.

“That aspect ratio is greater than that of any asteroid or comet observed in our solar system to date. While its elongated shape is quite surprising, and unlike asteroids seen in our solar system, it may provide new clues into how other solar systems formed,” the space agency explained.

NASA and other scientists suggest that the asteroid may have been wondering through the Milky Way for “hundreds of millions of years” before its “chance encounter” with our solar system.

“For decades we’ve theorised that such interstellar objects are out there, and now — for the first time — we have direct evidence they exist,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate in Washington.

Scientists found that the object was reddish in colour — similar to objects in the outer solar system. It was also found to be inert, lacking dust around it.

Astronomers think interstellar objects pass through the solar system roughly once a year, but we haven’t spotted one until now

So where did it actually come from? Well, it zoomed in from the direction of Vega, but it didn’t actually come from that particular star system.

“…it took so long for the interstellar object to make the journey — even at the speed of about 59 000 miles per hour — that Vega was not near that position when the asteroid was there about 300 000 years ago,” the space agency noted.

As of yesterday (20 November), ‘Oumuamua was travelling at 137 920 kph and was 200 million kilometres from Earth.

“The object passed Mars’s orbit around 1 November and will pass Jupiter’s orbit in May of 2018. It will travel beyond Saturn’s orbit in January 2019; as it leaves our solar system, ‘Oumuamua will head for the constellation Pegasus,” NASA elaborated.

Featured image: ESO/NASA screenshot