2014 comet may be first known interstellar visitor to have come close to Earth
Earth may already have been visited by an object from outside our solar system — a meteor that burned up in the planet’s atmosphere in 2014, astronomers claim. If confirmed, it would be the first known interstellar object to have entered the atmosphere.
The first interstellar visitor known to have come close to Earth was the roughly 400-meter-wide asteroid named ‘Oumuamua.’ It swooped within about 24 million kilometers of the planet in October 2017. Its sharp-angled approach to the solar system and equally strange departure led astronomers to suggest that ‘Oumuamua could have been anything from a fluffy skeleton of a comet to an alien spaceship.
If there was one interstellar interloper, astronomers reasoned, there would likely have been more, including some that collided with Earth. [Continue reading…]