Well. Not really solar system... But this dwarf star has very likely just passed through our Oort Cloud
QuoteA group of astronomers from the US, Europe, Chile and South Africa have determined that 70,000 years ago a recently discovered dim star is likely to have passed through the solar system's distant cloud of comets, the Oort Cloud. No other star is known to have ever approached our solar system this close -- five times closer than the current closest star, Proxima Centauri.
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In a paper published in The Astrophysical Journal Letters, lead author Eric Mamajek from the University of Rochester and his collaborators analyzed the velocity and trajectory of a low-mass star system nicknamed "Scholz's star."
The star's trajectory suggests that 70,000 years ago it passed roughly 52,000 astronomical units away (or about 0.8 light years, which equals 8 trillion kilometers, or 5 trillion miles). This is astronomically close; our closest neighbor star Proxima Centauri is 4.2 light years distant. In fact, the astronomers explain in the paper that they are 98% certain that it went through what is known as the "outer Oort Cloud" -- a region at the edge of the solar system filled with trillions of comets a mile or more across that are thought to give rise to long-period comets orbiting the Sun after their orbits are perturbed.
The star originally caught Mamajek's attention during a discussion with co-author Valentin D. Ivanov, from the European Southern Observatory. Scholz's star had an unusual mix of characteristics: despite being fairly close ("only" 20 light years away), it showed very slow tangential motion, that is, motion across the sky. The radial velocity measurements taken by Ivanov and collaborators, however, showed the star moving almost directly away from the solar system at considerable speed.
"Most stars this nearby show much larger tangential motion," says Mamajek, associate professor of physics and astronomy at the University of Rochester. "The small tangential motion and proximity initially indicated that the star was most likely either moving towards a future close encounter with the solar system, or it had 'recently' come close to the solar system and was moving away. Sure enough, the radial velocity measurements were consistent with it running away from the Sun's vicinity -- and we realized it must have had a close flyby in the past."
To work out its trajectory the astronomers needed both pieces of data, the tangential velocity and the radial velocity. Ivanov and collaborators had characterized the recently discovered star through measuring its spectrum and radial velocity via Doppler shift. These measurements were carried out using spectrographs on large telescopes in both South Africa and Chile: the Southern African Large Telescope (SALT) and the Magellan telescope at Las Campanas Observatory, respectively.
Once the researchers pieced together all the information they figured out that Scholz's star was moving away from our solar system and traced it back in time to its position 70,000 years ago, when their models indicated it came closest to our Sun. Until now, the top candidate for the closest flyby of a star to the solar system was the so-called "rogue star" HIP 85605, which was predicted to come close to our solar system in 240,000 to 470,000 years from now. However, Mamajek and his collaborators have also demonstrated that the original distance to HIP 85605 was likely underestimated by a factor of ten. At its more likely distance -- about 200 light years -- HIP 85605's newly calculated trajectory would not bring it within the Oort Cloud.
Mamajek worked with former University of Rochester undergraduate Scott Barenfeld (now a graduate student at Caltech) to simulate 10,000 orbits for the star, taking into account the star's position, distance, and velocity, the Milky Way galaxy's gravitational field, and the statistical uncertainties in all of these measurements. Of those 10,000 simulations, 98% of the simulations showed the star passing through the outer Oort cloud, but fortunately only one of the simulations brought the star within the inner Oort cloud, which could trigger so-called "comet showers."
While the close flyby of Scholz's star likely had little impact on the Oort Cloud, Mamajek points out that "other dynamically important Oort Cloud perturbers may be lurking among nearby stars." The recently launched European Space Agency Gaia satellite is expected to map out the distances and measure the velocities of a billion stars. With the Gaia data, astronomers will be able to tell which other stars may have had a close encounter with us in the past or will in the distant future.
Currently, Scholz's star is a small, dim red dwarf in the constellation of Monoceros, about 20 light years away. However, at the closest point in its flyby of the solar system, Scholz's star would have been a 10th magnitude star -- about 50 times fainter than can normally be seen with the naked eye at night. It is magnetically active, however, which can cause stars to "flare" and briefly become thousands of times brighter. So it is possible that Scholz's star may have been visible to the naked eye by our ancestors 70,000 years ago for minutes or hours at a time during rare flaring events.
The star is part of a binary star system: a low-mass red dwarf star (with mass about 8% that of the Sun) and a "brown dwarf" companion (with mass about 6% that of the Sun). Brown dwarfs are considered "failed stars;" their masses are too low to fuse hydrogen in their cores like a "star," but they are still much more massive than gas giant planets like Jupiter.
The formal designation of the star is "WISE J072003.20-084651.2," however it has been nicknamed "Scholz's star" to honor its discoverer -- astronomer Ralf-Dieter Scholz of the Leibniz-Institut für Astrophysik Potsdam (AIP) in Germany -- who first reported the discovery of the dim nearby star in late 2013. The "WISE" part of the designation refers to NASA's Wide-field Infrared Survey Explorer (WISE) mission, which mapped the entire sky in infrared light in 2010 and 2011, and the "J-number" part of the designation refers to the star's celestial coordinates.
http://www.sciencedaily.com/releases/2015/02/150217114121.htm
Interesting, Thanks! Solitary
It was 70,000 years ago! We had a brief encounter but it's over now.
Quote from: Jason78 on February 18, 2015, 02:27:51 PM
It was 70,000 years ago! We had a brief encounter but it's over now.
oh yeah... Still awesome to think about! :lol:
Give it up. She tickled our Oort cloud, but she's gone dude. Get over it.
She's gone, she's not coming back.
I feel so violated now. Our Oort cloud is a no-no place.
Quote from: Jason78 on February 18, 2015, 05:10:57 PM
Give it up. She tickled our Oort cloud, but she's gone dude. Get over it.
They say there are trillions of stars out there. But there will only be one WISE J072003.20-084651.2..... :(
Quote from: PickelledEggs on February 18, 2015, 05:25:03 PM
They say there are trillions of stars out there. But there will only be one WISE J072003.20-084651.2..... :(
She wasn't even that hot....
Quote from: Jason78 on February 18, 2015, 05:31:20 PM
She wasn't even that hot....
Hey! She was kind of cool! >:(
Let us all bow our heads in mourning of the lost love of our solar system
I found the study into how elliptical galaxies are formed really interesting, being the largest galaxies in the universe, clustered from billions of stars and solar systems over eons gathering together, star formations grouping and merging. I dare say our solar system will do the same with another galaxy one day.
Quote from: kilodelta on February 18, 2015, 05:22:32 PM
I feel so violated now. Our Oort cloud is a no-no place.
Show me on this planetarium where she touched you?
Are we pregnant?
Two strangers passing in the void?
Fascinating.
It occurs to me that a celestial body with more mass/a closer approach would guarantee the end of the world. The prospect of a neutron star passing close by or even directly through our own neighborhood is a really cool idea. We would never see it coming, and its likely everything would get slung into interstellar space.
Of course, I dont think we should ever worry about something like that, seeing that our own local planetary system has evidently remained quite stable for billions of years. The odds of something like this ever happening must truly be astronomical.
She told me I was her fisrt, thAT cloud LIED TO ME :(
I wonder if there is anything of note in the fossil record 70,000 years ago.
Sent from my Z936L using Tapatalk
Well 75,000 years ago we did have the big eruption on Sumatra, that nearly made humans extinct.
http://www.inquisitr.com/2160555/indonesias-lake-toba-supervolcano-threatens-global-volcanic-winter-eruption-caused-mass-extinction-75-000-years-ago/
So yes, there is evidence ... provided that the gravitational pull of a neutron star can make the Earth's crust more unstable in weak spots.
Quote from: Baruch on November 11, 2015, 09:48:09 AM
Well 75,000 years ago we did have the big eruption on Sumatra, that nearly made humans extinct.
http://www.inquisitr.com/2160555/indonesias-lake-toba-supervolcano-threatens-global-volcanic-winter-eruption-caused-mass-extinction-75-000-years-ago/
So yes, there is evidence ... provided that the gravitational pull of a neutron star can make the Earth's crust more unstable in weak spots.
Not really sure that these two items are related.......
Gerard
Timing coincidence between possible neutron star passage and major volcanic eruption? 70,000 vs 75,000 is pretty close.
Quote from: Jason78 on February 18, 2015, 05:11:51 PM
She's gone, she's not coming back.
70,000 years ago - isn't that when that big comet triggered the mass extinction event which killed off the dinosaurs, and gave rise to mammals? Goody for us and the pooches, and I'm really happy that I don't have to floss dinosaur teeth, but if it is coming back soon then we can expect all sorts of hell to break loose when it does.
Quote from: Baruch on November 11, 2015, 05:17:59 PMTiming coincidence between possible neutron star passage and major volcanic eruption? 70,000 vs 75,000 is pretty close.
Well, if we're going to ballpark it, the moon landing and the end of the Cold War happened at virtually the same time, too.
Quote from: Hydra009 on November 12, 2015, 12:20:10 AM
Well, if we're going to ballpark it, the moon landing and the end of the Cold War happened at virtually the same time, too.
There we have it, the Cold War ended with the rise of agriculture!
When I first came to this forum, there was this guy that used to get pissed off when anyone would reactivate and old thread like this one. He would get pricky and ask, "Why did you bump this thread? It's 9 months old."
Oh my. Someone bumped an old thread, and someone else might have responded. "Come on now people, you know that's wrong. It's just so wrong."
Mostly, I think he did it when he didn't approve of the response, not so much that some unspoken forum protocol had been ignored. Anyway, people don't seem to fuss over that anymore, and that particular individual that did all the time eventually got banned, although it was for some other dick-headed thing he was doing.
Now, when someone reactivates and old thread, I still flinch, like I'm waiting for a heavy hammer of disapproval to come down on the thread.
But thanks for re-opening this. I must have missed it before, and it is a most interesting bit of information. It points out how much safer we are here on Earth than out in space, which is filled with danger. You go out in space, and you could get clobbered with God knows what. Stay out of the way of neutron stars and major asteroids and comets and stuff. Don't go out in space.
Hall monitors demand you respect their authority!
Quote from: SGOS on November 12, 2015, 08:04:57 AM
When I first came to this forum, there was this guy that used to get pissed off when anyone would reactivate and old thread like this one. He would get pricky and ask, "Why did you bump this thread? It's 9 months old."
Oh my. Someone bumped an old thread, and someone else might have responded. "Come on now people, you know that's wrong. It's just so wrong."
Mostly, I think he did it when he didn't approve of the response, not so much that some unspoken forum protocol had been ignored. Anyway, people don't seem to fuss over that anymore, and that particular individual that did all the time eventually got banned, although it was for some other dick-headed thing he was doing.
Now, when someone reactivates and old thread, I still flinch, like I'm waiting for a heavy hammer of disapproval to come down on the thread.
But thanks for re-opening this. I must have missed it before, and it is a most interesting bit of information. It points out how much safer we are here on Earth than out in space, which is filled with danger. You go out in space, and you could get clobbered with God knows what. Stay out of the way of neutron stars and major asteroids and comets and stuff. Don't go out in space.
That dude sounds like at least two of the mods here, who aren't any different now. They know who they are, being the only mods who frequently troll these discussions as if they were regular members, only difference is that when they don't like your opinion they can and will ban you for any excuse they can cook up, and they will goad you toward that end - not very professional!
Quote from: peacewithoutgod on November 11, 2015, 11:58:16 PM
70,000 years ago - isn't that when that big comet triggered the mass extinction event which killed off the dinosaurs, and gave rise to mammals? Goody for us and the pooches, and I'm really happy that I don't have to floss dinosaur teeth, but if it is coming back soon then we can expect all sorts of hell to break loose when it does.
Seriously? Dinosaurs were 66 million years ago, not 70 thousand ;-(
I remember my uncle talking about this a few months ago. He thinks it's Planet Nibiru.
Quote from: Hijiri Byakuren on November 12, 2015, 01:10:24 PM
I remember my uncle talking about this a few months ago. He thinks it's Planet Nibiru.
That's really unfortunate.
Gerard
Quote from: Baruch on November 12, 2015, 12:59:06 PM
Seriously? Dinosaurs were 66 million years ago, not 70 thousand ;-(
Damn, I knew that!
Maybe there was another comet strike of slightly lesser global around 70,000? I thought I read something on that, but it was so long ago, and time muddles everything!
It's interesting that 70,000 years ago is about when a population bottleneck happened, but that was apparently the result of volcanic activity, when Toba exploded (https://en.wikipedia.org/wiki/Toba_catastrophe_theory).
Quote from: Unbeliever on November 12, 2015, 04:05:38 PM
It's interesting that 70,000 years ago is about when a population bottleneck happened, but that was apparently the result of volcanic activity, when Toba exploded (https://en.wikipedia.org/wiki/Toba_catastrophe_theory).
Yes. And the Oort cloud is somewhat further away from us than Toba.
Gerard
Quote from: peacewithoutgod on November 12, 2015, 03:08:01 PM
Damn, I knew that!
Maybe there was another comet strike of slightly lesser global around 70,000? I thought I read something on that, but it was so long ago, and time muddles everything!
Comets and asteroids frequently go on strike, they are more Left than the machinist union ;-)
Quote from: Gerard on November 12, 2015, 06:06:11 PM
Yes. And the Oort cloud is somewhat further away from us than Toba.
Gerard
If a neutron star had struck the Earth, we wouldn't be talking about it. If it came within the Solar System close enough to Earth, it might have stressed tectonic plates. If it went thru the Oort cloud, it could have dislodged a bunch of comets. It's a small solar system after all, it's a small solar system after all ...
Quote from: peacewithoutgod on November 12, 2015, 03:08:01 PM
Damn, I knew that!
Don't feel bad, I read it the same way. I keyed in on dinosaurs/70,000, and thought it sounded in the ball park.
I was going to suggest Barringer Crater (aka Meteor Crater) in Arizona as being the impact event, but that was "only" 50,000 years ago. Close, but no cigar, and it was small enough that its environmental impact was regional -- the 'kill zone' was less than 15 miles in radius:
(http://www.lpi.usra.edu/science/kring/epo_web/impact_cratering/enviropages/Barringer/barringereffectsweb1.jpg)
I can't find any known or suspected impacts dated to 70-75Kyears ago to coincide with the Toba eruption, so it looks like space was innocent of that one.
Quote from: trdsf on November 22, 2015, 06:37:47 PM
I was going to suggest Barringer Crater (aka Meteor Crater) in Arizona as being the impact event, but that was "only" 50,000 years ago. Close, but no cigar, and it was small enough that its environmental impact was regional -- the 'kill zone' was less than 15 miles in radius:
(http://www.lpi.usra.edu/science/kring/epo_web/impact_cratering/enviropages/Barringer/barringereffectsweb1.jpg)
I can't find any known or suspected impacts dated to 70-75Kyears ago to coincide with the Toba eruption, so it looks like space was innocent of that one.
No ... no ... a dwarf star impact or neutron star impact would be big enough that a volcanic eruption would be tiny. I am talking about crustal distortion due to strong gravitational fields ... and obviously when such a monster would be well within the inner solar system temporarily not while in the Oort Cloud.
If there were a massive object in orbit around the sun, its presence would be already known from the distortion it would induce on the orbits of the other planets. Considering that the precession of Mercury's perihelion was known long before Einstein (whose General Relativity explained it) and that the movement measured was 0.16° per century, the presence of another massive object in the solar system -- even at the range of the Oort cloud -- cannot remain hidden.
Had a 'rogue' massive object transiting the solar system some 75Kyears ago or so, that also has a few problems. First, if it's massive enough to have a serious gravitational impact, we should see higher eccentricities at least in objects that are Earth-crossing, especially the Moon. Second, if it were small enough to not have an observed gravitational impact on other planets and the Moon, then it's unlikely it would have one on the Earth. Certainly if something passed close enough to tidally stress the crust of the Earth, there should also be recognizable damage to the Moon.
I don't think there's any need to call on any outside forces to explain the Toba eruption. Large-scale volcanic events happen on a planet with an active geology, especially when your clock is on geological time.