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Nemesis, the Sun's Binary Star Companion?
0xC2 writes "The Binary Companion or 'Nemesis' theory asserts that a yet-to-be discovered companion to our Sun may actually exist. Recent observations of two nearby stars (assumed companions) show debris disks 'strikingly like the Kuiper Belt int the outer part of our Solar System'. The Binary Research Institute site is devoted to the theory, and presents a concise introduction, list of evidence, and sample calculations in support of the theory. A fascinating read, although the physics and related calculations are not trivial." Has the 'unique theory on the internet' vibe to it, but interesting nonetheless.
Isn't that Microsoft? Oops... Wrong article...
I sense an evil twin joke coming on.....
On a scale of "faked moon landing" to "electric universe", I rate this 'theory' a solid "roswell alien autopsy"
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As the slashdot crowd is pretty much clueless about astronomy I expect lots of Funny rated comments to hide our ignorance on the subject, right guys?
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Scientific Amercian ran a story several years ago about this. One of the pet theories at the time was that periodic extinctions (which haven't been proven periodic) were caused by objects like comets getting kicked out of the Oort every now and then which could in turn be explained by just such a neighbor star. Nasa has a (very short) page here: Imagine the Universe
An actual brown dwarf isn't likely given scarce evidence but there seems to be reason to believe there are one or more large Kupier Belt objects yet to be found. I've read about gravitational anomalies for years now but they just don't seem large enough to indicate a failed star close enough to call us a near miss binary system. I guess if all the outer planets merged we'd have the makings of a brown dwarf but as we are the system seems to be one of those rare single star systems.
... could we possibly find the outer planets by observing their influence on the inner planets' orbits, if there were a freaking brown dwarf in the neighborhood that we didn't know about?
Something like that would've ruined Kepler's whole day.
The summary states...
Recent observations of two nearby stars (assumed companions)
Whereas the space.com article states...
Each of the two disks has a sharp outer edge that might be caused by an unseen companion star
READ THAT AGAIN FOLKS - they are NOT assuming these two stars are companions. They are NOT a binary star system. They are simply two stars that have similar disks as our own solar system. They think a POSSIBLE cause for these disks MIGHT be an unseen companion, but NO unseen companion has been seen. This discovery leads NO MORE CREDIBILITY to the nemesis "theoory" whatsover - all it says is that there are other stars with similar structures to our own. The cause of this structure has not been observed.
Twins are hot!
At the distances involved (in the outer reaches of the kupier belt, about a light year), I guess we wouldn't really notice anything but a brighter star, but I still don't really think this is a possibility. Do the math: v=sqrt(Gm/r) where G is 6.67*10^-11, m is the mass of our sun, and r is the distance between them... 1.21746415*10^-6 meters per second orbital velocity. That's about one meter every 9.5 earth years. Anyone else think that seems a bit... unlikley? Also, the of gravity between the earth and the sun is about 1000 times as strong as with another star of the sun's mass one light year away. I don't think such a system would be stable, as a large astroid passing close to one might well pull it enough out of "orbit," if you can call such a small speed "orbit," so that you'd notice it was no longer binary. For the record, at one AU distance, it would take the system 5.64701404*10^17 years for an orbit. That's like 10 order of magnitude longer then the sun's life span.
Does a line appended to your comment give your post meaning in and of itself, or only in relation to those without?
SETI is the Search for Extra Terrestrial Intelligence, they do not involve themselves often in cosmological debates, instead they focus on mapping radio signals from numorus star systems. The radio signals they recieve however have led cosmologists to discover a number of special objects in space.
NASA might have been a better choice for inclusion in your parent post, or better yet a astonomological group.
Isaac Asimov has a novel with this exact premise, written in 1989, titled Nemesis (as if you expected something different). "Evil" companion star for the sun which caused all the mass extinctions, etc. Of course, in the novel there are multiple civilizations, a battle over whether Earth should be saved, etc... but the basic premise is the same. 17 years later, still just as fictional as it was then.
You don't need a companion to produce a sharp edge in the Kuiper belt. Simulations have shown that. Anyone who makes the assertion that the edges suggest such a thing ought to have at least become familiar with that research.
Furthermore, the analogy to Saturn's rings is, I suspect, misleading. The moons that directly shape the outer edge of the A ring are close to the ring and small. (They are tied to other moons via resoances so the whole system is strung together, but that's not what's being argued for here.) A star would be much more massive than the Kuiper belt and would seriously disrupt the system rather than maintain it. (It would also be pretty obvious if it were just beyond the orbit of the outer edge of the Kuiper belt. We'd feel it here, for a start.) A more distant star might be able to hold back the edge of the belt with a resonance, but that's a different thing. And odds are that such a companion would destroy a belt more readily than maintain it. (Look at Jupiter and the asteroid belt.)
It should also be noted that 300 million years is a short time in solar system terms. It's even shorter for the outer solar system where it's about one million orbits. Since things move slowly and there is little material out there, spreading is very slow. Ones the material is placed there by a larger body (like Neptune), it tends to stay put for quite a while.
If you convert that message back to ASCII, you will find that it is ontopic and actually quite funny.
I would think for such a claim one would need more than just simple calculations .
But anyway, in other news: "Dark matter coming to a store near you."
With all this pseudoscience crap floating around on slashdot we should open a horoscope section. It would make sense. But in all seriousness there is a possibility of a binary companion, but, this site is nothing more than pseudoscience. It dresses up a crazy astrology theory with a little bit of modern scientific sounding language. Be careful about what you post.
Are they suggesting that there may be a nearby star that astronomers have just failed to see for the past few millenia that we've been studying the sky? I thought the nearest star was light years away. Is it a very dim star? I don't get it!
If you can read this sig, you're too close.
http://www.exitmundi.nl.nyud.net:8090/Nemesis.htm
I actually re-read this article the other day. I had been visiting the site because of an odd 43 degree F temperature change overnight, and decided to check on that again. A temperature change of such a large amount, overnight, is not normal at all during January in NY. All the snow melted overnight.
I don't think you truly appreciate how BIG our solar system is. If there's a twin to our star, it would seem so far away that it would seem like it had nothing to do with us. e.g. From Pluto, our Sun looks like nothing more than a particularly bright star. Now given how far away this star would be, its gravitational effects might be difficult to detect. In fact, IIRC, there are still quite a few odd effects that the discovery of Pluto didn't quite account for. (Not big enough.) So maybe we've finally found our Planet X. Except that it isn't a planet at all. :-)
Javascript + Nintendo DSi = DSiCade
All these world are yours except Europa. :hammertime:
Use them together.
Use them in peace.
I knew that getting this username before anyone else would one day pay dividends! Username/name of star are inspired by the Isaac Asimov novel "Nemesis" by the way.
100 comments about Nemesis AND Stars and no Resident Evil reference?
"STAAAAAAARRRSS...."
If the Sun turns out to be binary, what the hell will the Gentoo guys do, CCFLAGS="-Odamnimcold -DALPHA_CENTAURI -funroll-solar-panels"?
Erlang.org: wow
In the Asmov Gold book, he actually talks about how the idea for the novel sprung from this theory. That's actually how the novel got its name, heh.
You mean this Capt. Picard?
The linked article is not really about Nemesis, a distant companion to the Sun supposedly linked to regular massive exctinctions through its influence on the Oort cloud (where comets come from).
It is, however, about an unseen Sun companion responsible for the precession of the equinox. The precession of the equinox is the observation that as the Earth orbits the Sun, after a full year around the Sun the Earth does not realign itself with the distant stars, there is a difference of about 50 arcseconds. This correspond to a period of about 24,000 years.
Current theory for precession says the phenomenon is due to tidal effects due to the Moon acting on the non-perfectly-spherical Earth.
TFA makes the simple point that this could be also more easily explained if the Sun was revolving around an heretofore unseen companion for the same period. This would also explain a number of other more complex phenomena, such as why this the precession rate seems to slowly, but undoubtedly change with time, why the angular momentum of the Sun appears to be so low compared to that of the planets, etc.
TFA goes on to make prediction where this companion might be in the sky, and how far away it should be (between 0.01 and 0.03 of a LY), using nothing more complicated than basic Newtonian celestial mechanics.
Well, time will tell, and I'm not an astronomer, but the theory is actually very simple and testable (in the mid to long run), so either evidence will mount in this direction or it will be disproved.
For example we could measure precession rates on Mars. Since Mars has no large satellite, if it is found to have a precession rate similar to that of the Earth, then this will be very strong evidence that the tidal theory cannot be correct, and that the distant companion one is more likely to be. On the other hand if precession on Mars is very low, then this theory cannot be correct.
In short I think the guy might be wrong but he is no crackpot.
"I don't think you truly appreciate how BIG our solar system is. If there's a twin to our star, it would seem so far away that it would seem like it had nothing to do with us."
And I don't think you realize how big and bright stars are and how long we've been tracking the movement of stars across the heavens. If you have a star identical to the Sun 100 AU away (Pluto is 50 at its greatest), it will still be 40 times brighter than the full moon. I daresay that night as we know it wouldn't exist for months out of the year. And it would move noticably among the background stars (if you could see any) over the course of months or, at most, years (a drop in the bucket compared to the astronomical data we've collected since the development of written language). And there'd be no doubt even to Tycho Brahae that this one particular star/planet showed parallax and probably even measurable retrogade motion.
If the species can find something as small (0.00004 solar masses), dim (no fusion) and distant (20 AU, only 0.0003 light-year) as Uranus during the American Revolution, we'd certainly have found any kind of star closer than Alpha Centauri (let alone within the heliopause) by now, even if it were a black hole.
"Now given how far away this star would be, its gravitational effects might be difficult to detect."
Our sun is over 1000 Jovian masses, 1,300,000 earth masses, and 13.1E21 Pluto masses. The majority of all matter in the solar system is in the sun. It's certainly not something you can hide.
"In fact, IIRC, there are still quite a few odd effects that the discovery of Pluto didn't quite account for. (Not big enough.)"
You see: waves in a pond
You find: a 1 g tadpole
You'd expect: an 8 kg fish
Nemesis: 94 million blue whales put together
*cough*
A quick read of the article was also able to confirm that they are proposing a brown dwarf or a small singularity, not a yellow star like Sol.
Again, I'm not saying the guy is right. Just that space is a BIG place that can easily hide such things. If he can find a binary twin, then more power to him. If not, well he'll be in good company with many other scientists.
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While I agree that this theory sounds... a little off, there remains many unexplained myths that have tantalizing bits of truth to them.
For instance, see the Dogon's well documented belief in a binary system, that was later revealed to be true. http://en.wikipedia.org/wiki/Sirius#The_Dogons
The Dogon issue is of course, debatable. Regardless, it is interesting to speculate about.
We now know that solar system travels up and down through the galactic plane in a regular cycle, and some have speculated that this particular cycle brings with it increased chances of asteroid impact, as well as yet unforseen forces (for instance, gravitational).
Who knows what odd galactic cycles we'll discover in the future? I, for one, don't find the intense ancient interest in the sky and its movements, to be something that we can mearly attribute to some sort of primitive fascination with bright and shiny things alone.
Rather, I think there is probably some truth to the many, many myths concerning disasters, floods, and dramatic climate changes, and these were in some way linked to observable heavingly events. That probably greatly contributed to almost every known culture having an intense interest in the sky, with the greatest well known ancient cultures having such well known, and seeminly overly complex, obsessions with the movements of the stars and planets.
Proxima Centauri, a red dwarf, is 0.12 solar masses, about 270,000 AU away, and was discovered in 1915.
It seems brown dwarfs cap at around 90 jovian masses (0.08 solar masses).
"The Nemesis theory says that it exists about 50,000-100,000 AU away, has an orbital period of 26 million years, and is a brown dwarf."
ballpark absolute magnitude of a brown dwarf: 17
absolute magnitude of the sun: 4.8
difference: 12.2
Apparent magnitude of the sun at 1 AU: -26.73
apparent magnitude of sample dwarf at 1 AU: -26.73 + 12.2= -14.53
Add 5 apparent magnitude for multiple of ten of distance
100,000 AU = 10^5 AU, 5 * 5 = 25, 25 + (-14.53) = 10.47
Apparent magnitude of sample dwarf at 100,000 AU = 10.47 (round to 11)
Coincidentally, the apparent magnitude of Proxima Centauri is also 11
Apparent magnitude of Neptune, discovered 1846 = 8 (about 16 times brighter)
Apparent magnitude of Pluto, photographed 1915 = 14 (about 16 times dimmer)
Apparent magnitude visible by ground-based telescopes = 27 (2.5E6 times dimmer)
Apparent magnitude visible by Hubble = 30 (4.0E7 times dimmer)
From the looks of things, Nemesis would have been showing up in astronomical photographs starting from the last decade or so of the Nineteenth Century. Curiously, the first confirmed sighting of a brown dwarf was in 1995 (first theorized in the 1960s). Now, unless the spectral pattern put out by this brown dwarf Nemesis somehow looks like much larger, hotter and brighter stars, it would have been Big News in Astronomy that such an odd star exists, regardless of its distance from us.
"It's like putting a telescope in your car while driving down the road and expecting to be able to find a parallax between observations"
Time between the two photographs over which the motion of Pluto first became apparent: 6 days
Orbital period of Pluto: 90,600 days
Sweep of arc made by Pluto for its discovery ~ 1 minute, 16 seconds of arc
Time between the two photographs over which the motion of Quaoar first became apparent: 180 minutes
Orbital period of Quaoar: 105,000 days
Sweep of arc made by Quaoar for its discovery ~ 1.5 seconds of arc
You say Nemesis may have an orbital period of 26 million years. Kepler says an object 100,000 AU away should have an orbital period of about 32 million years. We'll take the slower number:
Sweep of arc made by Nemesis in the past 50 years ~ 2 seconds of arc
And an interesting quote about the discovery of real nearby brown dwarfs in Epsilon Indi, 12 light-years away (source):
If 12 light-years "appears to move quite rapidly in the sky," why not 1.2 light-years?
I prefer Adcott's Binary Translator, mainly because I can remember the URL. ;)
Keep your eyes to the sky.
"I'm not sure if I can agree with your magnitude numbers for a brown dwarf."
I got the +17 number from here. For the record, 17 is pretty damned dim: Proxima Centauri has an absolute magnitude of 15.49. But even if you unrealisticly want to bump up Nemesis' absolute magnitude to 30, at 100,000 AU (twice your largest claim) it'd still have an apparent magnitude from earth of 24, still 16 times brighter than what modern ground-based telescopes can see. All you'd be doing is limiting the data that should be available on Nemesis to 80 years instead of 120.
"Each of these brown dwarfs are warm objects that emit a reasonable amount of infrared radiation. If it is a cold black dwarf similar to a larger Uranus--~60 K (and less than 13 Jupiter masses so that it can't have fusion)"
Aside from the fact that we'd still be able to see it, with 13 Jovian masses at 25,000 AU (half your smallest claim), the gravitational attraction on the sun would be 0.117 pm/s^2 (that's picometers). The center of the galaxy exerts an acceleration on the sun of 19,330 pm/s^s. Nemesis' gravitational influence would be indiscernible and meaningless compared to the gravitational effect of the rest of the galaxy. Its influence on us would literally be background noise, unless one tries to claim it influences us in some way other than gravity (*cough* astrology *cough*)
The article theorizes that the putative brown dwarf culprit may have been missed if it were located in a region of the sky with lots of stars as background, e.g. the milky way. In fact it could be anywhere and could have been missed easily.
The scientist who found Pluto was looking for it, was very talented and got lucky.
I don't think the whole sky is being surveyed for moving objects. Indeed a recent piggyback project that used serendipitous tracks on Hubble plates discovered hundreds of asteroids. Yet asteroids are much more numerous, typically brighter and move much more quickly across the sky than any brown dwarf that would fit the data. To find them the Hubble scope made use of very long exposures and of the huge parallax the telescope had while orbiting the Earth.
Hence the hypothesis of an as-yet, undiscovered close-by brown dwarf is not implausible.
BTW I tried to help for the asteroid Hubble project in a small way by automating the finding of the hallmark tracks, but it turned out using graduate students was faster and more efficient.