Last month, a telescope at the Haleakala Observatory on the island of Maui in Hawaii detected the first observed object to enter our solar system from outside of it. While it’s estimated that a handful or so of such objects traverse our system each year, this is the first time one has been seen.
Dubbed 1I/2017 U1, and also known as ‘Oumuamua (“a messenger from afar arriving first”), the object is an elongated asteroid which is thought to have come from the region of Vega in the constellation of Lyra. Its trajectory is taking it through our solar system en-route to the constellation of Pegasus. Currently, it is between Mars and Jupiter and will pass Saturn in January 2019 as it continues its journey outside of our solar system.
As mentioned, this is the first time that such an interstellar traveller has been observed. The object is 400 meters long and possibly only 40 meters wide (it is reported as being extremely and unusually elongated). It is believed to be composed of rock and metals, with no water or ice. Its speed relative to the sun is approximately 85,700 miles per hour.
The NASA website has additional information about ‘Oumuamua as well as an animated map of the solar system depicting its path.