Slashdot Mirror
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.
oooW
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.
Why does it especially have to come from outside to be "captured" by Jupiter?
No, your children are not the special ones. Nor are your pets.
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!
It can just as well be, that it merely got turned around by getting too near to Jupiter and swinging around.
It is a well-known hypothesis that Jupiter protects the inner planets from asteroids coming from the outer solar system.
It is not captured by (not in orbit around) Jupiter. It is the fact that it orbits the Sun in opposite direction that is a clue that it likely comes from outside the solar system.
Within the solar system all orbits around the Sun are in the same direction because of how the planets etc formed: from a dust/gas cloud that has some residual orbital motion.
A journalist just caught the tail end of an epic diss-fest between two astronomers asserting that "your mama so fat..." ;)
Anons need not reply. Questions end with a question mark.
Several, like BZ509, are known to have retrograde paths, although how they ended up on such orbits is unclear.
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.
This is speculation, but in principle we can get retrograde orbits if an asteroid -- even one on a "normal" orbit direction -- passes in front of a planet (relative to its path in orbit) and gets slingshot back around exiting at a ~200-300 degree angle. Whether this is possible in practice depends on the relative asteroid speed and mass of planet.
Watch out for the Vex.
"interstellar immigrant" ? They can be stopped!
-Unresolved symbol? Byte me!
.fff
Fucking immigrants, again!!
From outside the solar system you say. And reasonably easy to find and locate. Yep, that is where the proto-molecule is.
((The Expanse reference))
Stop making everything about immigration.
I'm only going one way!
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.
Run any gravity sim with a bunch of masses around a central mass. You'll get some going one way, some going the other way. Add some initial spin and you'll still get the oddball object that rotates the "wrong" way.
TL;DR: Jumped to conclusions, there's zero evidence the object is from outside our system. In fact, I'd bet my life that it isn't...
Fucking immigrants, again!!
No. no.. It's not immigrant objects you fool, everything isn't from here originally.. It's the UNDOCUMENTED objects we need to fear. Always going the wrong way, don't know the local laws or language and crashing into things...
Isn't that what the Ort Cloud is? Or at least the beginning of?
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Illegal interstellar immigrants breaking orbiting laws. We need to build a Dyson Sphere (and make Mexico pay for it!).
Much like how we already have a border checkpoints on roads, and fencing and a wall along the more populated areas of the border?
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Much like how we already have a border checkpoints on roads, and fencing and a wall along the more populated areas of the border?
Works just like gun control.
TK7 spends half its time retrograde as it shares the Earth's orbit around the sun. I don't think retrograde necessarily has to imply extra-solar. Run a multi-body simulation of the early solar system ... you will see pure chaos and many masses of different sizes being ejected and nearly ejected on odd trajectories. Having one small mass come out of that chaos retrograde does not seem implausible.
Itâ(TM)s a space station!
Did you seriously not get that I said that the hypothesis is a retarded one, given far more obvious ones,or did you just /have/ to grab that straw-man, just to attack something?
Please go meet some actual humans, and learn some common sense and common implications.
Yes, that was exactly my point above.
Plus, Jupiter is well-known (well, at least well-hypothetized) to do exactly that, protecting us from inbound asteroids.
Asteroid driver D. Duck was heard to say, "Oopf! Put the silly thing in reverse!"
Think the laws don't apply to them.
Have gnu, will travel.
One has to wonder how long it can cross Jupiter's orbit (in the opposite direction, no less) before the two eventually meet?
I'm sure the encounter will be more detrimental to the asteroid than to Jupiter.
And when we send a probe to it, we know what we'll see... don't we, Mr. Clarke?
#insert "ThusSpakeZarathustra"
Personally, I think such probes should be mass-produced because there's no shortage of stuff in the solar system to go explore. Fire out a craft to land on the surface, deploy a small core sampler, and analyze its composition, comparing it to other "native" neighbouring asteroids...
This small rock will provide some lucky astronomers with an entire career's worth of knowledge and investigation. Gotta say, I'm kind of jealous.
Are you sure it isn't just a British asteroid?
Yes. If it were it would be brexiting the solar system not remaining.
Grab the harpoon!
/s, seriously, fuck the ESA but we should check this out.
That it's retrograde doesn't tell you it's extra-solar. But it does tell you "hey, this this is weirdly anomalous and you should look at it harder than more mundane objects." And its chances of being extra-solar are higher than the chances are for the gazillion objects that are orbiting in the "right" way.
Thats hardly fair.
The Alpha Centorians worked hard to build their Oort fence around us..
Triton also orbits in retrograde and could just as easily have originated from a different solar system. Sure the popular theory is that it is a Kuiper Belt object, but we don't know that for sure...do we? Also, just because something is in prograde doesn't mean that it must have exclusively formed during the accretion of the solar system. Just give us the science please and stop with the conclusions as fact. Amazingly, this article seems to conclude all the facts in evidence to the point of being a religious mandate. "No more science to be done here, we know what happened because we removed all the variables that we choose to consider...move along pleebs."
Is this asteroid similar enough to Jupiter in its distance from the Sun that Jupiter can be said to have not fully cleared its orbit?