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Asteroid From Another Star System Found Orbiting Wrong Way Near Jupiter (theguardian.com)
Astronomers have spotted an asteroid orbiting our sun in the opposite (retrograde) direction to the planets. The 2-mile-wide asteroid, known as 2015 BZ509, is the first "interstellar immigrant" from beyond our solar system to remain, according to the study published in the journal Monthly Notices of the Royal Astronomical Society. The Guardian reports: Further work on the asteroid revealed it takes the same length of time to orbit the sun as the planet Jupiter at a similar average distance, although in the opposite direction and with a different shaped path, suggesting the two have gravitational interactions. But unpicking quite where the asteroid came from was challenging. Asteroids that orbit the sun on paths that take them between the giant planets -- Jupiter, Saturn, Uranus and Neptune -- are known as centaurs, and it is thought that many might come from distant bands of material within the solar system such as the scattered disk or the Oort cloud. Several, like BZ509, are known to have retrograde paths, although how they ended up on such orbits is unclear.
But there was a clue there was something unusual about BZ509: while previous studies suggested retrograde centaurs stay gravitationally "tied" to planets for 10,000 years at most, recent work had suggested this asteroid's orbit had been linked to Jupiter for far longer, probably as a result of the planet's mass and the way both take the same time to orbit the sun. The discovery provides vital clues as to the asteroid's origins. [Dr Fathi Namouni from the Observatory de la Cote d'Azur said] that the model suggests the most likely explanation is that the asteroid was captured by Jupiter as it hurtled through the solar system from interstellar space. "It means it is an alien to the solar system," he said.
But there was a clue there was something unusual about BZ509: while previous studies suggested retrograde centaurs stay gravitationally "tied" to planets for 10,000 years at most, recent work had suggested this asteroid's orbit had been linked to Jupiter for far longer, probably as a result of the planet's mass and the way both take the same time to orbit the sun. The discovery provides vital clues as to the asteroid's origins. [Dr Fathi Namouni from the Observatory de la Cote d'Azur said] that the model suggests the most likely explanation is that the asteroid was captured by Jupiter as it hurtled through the solar system from interstellar space. "It means it is an alien to the solar system," he said.
Actually, they have do idea if it is the first extra-solar visitor or not. It is simply the first one they have noticed, and that was only because of its peculiar orbit. There could be a hundred others that either orbited with the planets, or that crashed into a planet or the sun. We'll never know.
If you think I voted for Trump because of this post, you're wrong. I voted for Dr. Jill Stein of the Green Party. Again.
Now we know how our Octopodian Overlords got here.
The only remaining loose end to this mystery is whether they consider Pluto a planet.
Sheesh, evil *and* a jerk. -- Jade
Are you sure it isn't just a British asteroid?
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
In any space game this unusual object would certainly be an important artifact.
In reality it would still be quite interesting to analyse its composition.
Lets build a Dysonsphere along the Oort Cloud and have the Alpha Centorians pay for it.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.