A cigar-shaped comet named 'Oumuamua sailed past Earth last month and is the first interstellar object seen in the solar system. It was first spotted by a telescope in Hawaii on 18 October, and was observed 34 separate times in the following week. Travelling at 44 kilometres per second (27 miles per second), the comet is headed away from the Earth and Sun on its way out of the solar system. The comet is up to one-quarter mile (400 meters) long and highly-elongated - perhaps 10 times as long as it is wide. That aspect ratio is greater than that of any asteroid or comet observed in our solar system to date. But the comet's slightly red hue — specifically pale pink — and varying brightness are remarkably similar to objects in our own solar system.
WHERE DID IT COME FROM?
Most comets follow ellipse-shaped orbits around the sun. But this comet appears to orbit at an angle, and doesn't circle the sun. Its orbital path suggests it entered our solar system from the direction of the constellation Lyra, looped around the sun, and will never return. But others have suggested that the comet did come from Earth, but interacted with Jupiter or another planet, which changed its orbit.