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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.
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
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.
Ancient folklore from around the world rings with two resonating themes: History moves in cycles with alternating Golden and Dark Ages, and the slow movement of the stars across the sky, the Precession of the Equinox, is the cause and timekeeper of these cycles. For years we have heard that these are only myths, there was no Golden Age and precession is just a wobbling of the Earth's axis. Now "Lost Star of Myth and Time" shows evidence the Ancients were not just weaving fanciful tales - science is on the verge of an amazing discovery - our Sun has a companion star carrying us through a great cycle of stellar influences. If true, it means the Ancients were right and our views of space and time and the history of civilization will never be the same. More than that, it would mean we are now at the dawn of a new age in human development and world conditions.
And the book gets a rave review from none other than the influential LA Yoga Magazine. You can't argue with a major astrophysical journal like that (http://www.loststarbook.com/). Clearly, this man and his theories demand to be taken seriously. Thank you, Zonk, for continuing to bring us only the finest in science journalism.
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
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.
you might have to check your maths there. I haven't checked the validity of your other calculations but considering you let this whopper through I can probably dismiss them all as false, since it doesn't lend you much credability. Anyone with a basic grasp of astrophysics would know that an orbit at a distance 1 AU around our Sun takes exactly 1.0 Earth years to complete. It doesn't need to be calculated because we have a good example of this kind of orbit (eg. our planet).
Rotation time depends on the object being rotated around, not the object doing the rotation. Of course, when you're talking about a companion star, it's gravity is large enough to change this, however, because the gravitic pull between the two objects is greater, the orbit is shorter.
go buy yourself a new calculator
being vague is almost as cool as doing that other thing...
"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.
Javascript + Nintendo DSi = DSiCade
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?
Don't be afraid of the skull - link is safe
I prefer Adcott's Binary Translator, mainly because I can remember the URL. ;)
Keep your eyes to the sky.
Brown dwarfs max out at about 29,000 Earth masses, and the distance of Nemesis wuld be no closer than a light-year or so (63,000 AU). Gravity follows an inverse-square of the distance law.
The Earth masses divided by approximate average AU distance squared value for the pull of Neptune's gravity on Uranus is ~0.02, with a max at closest approach of ~0.14. The equivalent value for the pull of Nemesis on Uranus is ~0.000007.
So, the average gravitational pull of Neptune on Uranus is about three thousand times greater than the pull of Nemesis, if it exists, on Uranus. The pull of the Earth on Uranus works out to about three hundred and fifty times the pull of a maximum-size Nemesis on Uranus. This means the pull of Nemesis on the solar system is so low as to be lost in the noise of orbital measurement and planetary mass estimate errors.
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.