Nine months after a mysterious interstellar object zipped past Earth, NASA has finally been able to derive a few facts. Oumuamua whipped past our planet at an unusually high speed in October 2017. This mysterious visitor is the first object ever seen in our solar system that is known to have originated elsewhere, said NASA in a tweet on Wednesday.
Interstellar object 'Oumuamua perplexed scientists in 2017 as it whipped past Earth at an unusually high speed. This mysterious visitor is the 1st object ever seen in our solar system that is known to have originated elsewhere. Here's 5 things we now know: https://t.co/htKrZfxxbt pic.twitter.com/K9xGuINayD
— NASA (@NASA) June 27, 2018
Due to its high speed, scientists were never able to take a close photo of Oumuamua.
Below, NASA explains 5 facts on the unknown object from beyond the solar system:
1. Outside the solar system “Because of its high speed (196,000 mph, or 87.3 kilometers per second) and the trajectory it followed as it whipped around the Sun, scientists are confident 'Oumuamua originated beyond our solar system,” said NASA. It went on to explain that Oumuamua's high speed cannot be just because of the gravity of the Sun. “So it must have approached the solar system at an already high speed and not interacted with any other planets.”
2. Hyperbolic trajectory Oumuamua is not following an elliptical path, making it unlikely to cross paths with earth or our solar system. Instead, it will follow the shape of a hyperbola and keep on going out of the solar system.
3. Not a comet, but has comet-like traits Scientists initially thought the object is a comet with an icy body and a tail of vaporizing substances due to Sun's heat. “But because 'Oumuamua appears in telescope images as a single point of light without a coma, scientists then concluded it was an asteroid. But when astronomers saw the object was accelerating ever so slightly, they realized that a coma and jets might not be visible to the telescopes used to observe it,” said NASA.
4. Elongated Oumuamua is estimated to be about half a mile (800 meters) long. Astronomers had never seen a natural object with such extreme proportions in the solar system before. 'Oumuamua, its dramatic variations in brightness over time suggest it is highly elongated. By calculating what kind of object could dim and brighten in this way, scientists realized the object must be up to 10 times as long as it is wide,” said NASA.
5. Free tumble Unlike most objects that rotate around one axis, Oumuamua is tumbling across the space and likely has a second axis too. The object appears to make a complete rotation every 7.3 hours, added NASA.