Talk:Nemesis (star)

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[edit] Distance units

Surely, you mean 24 billion kilometers? --Anon


Richard Muller has postulated an orbit around the sun that extends from 1-3 light-years. One light year is approx. 10 trillion kilometers.

[edit] Dating of theory

Does this theory predate or postdate Isaac Asimov's book Nemesis? In either case, should a reference to it be made? — Jor (Talk) 14:56, 25 Mar 2004 (UTC)

The theory came first. --Dragons flight 23:30, Mar 25, 2004 (UTC)
But star wars came even before that. so perhaps the "death star" mentioning is incorrect?
A reference to the book is probably not needed, although it is about a planetary system around a red dwarf star called nemesis the star is not a companion star to our own. Allywilson 17:34, 14 March 2007 (UTC)

[edit] Shouldn't we have found it already?

I'm little initiated in astronomy, but I am interested. I have a question: If Nemesis exists, it is the second closest star to Earth, and however small, much bigger than any planet, and however weak, emitting at least some light itself. How is it then possible that we can't see it with the most advanced telescopes we have got? --Caesarion 10:09, 11 Feb 2005 (UTC)

I checked it out myself: If Nemesis exists we can see it with even a small telescope; we just have to identify a star (of 3,000 candidates), e.g. by checking its distance to Earth with the parallax method. --Caesarion 10:23, 11 Feb 2005 (UTC)
Some people have also proposed that it could be a brown dwarf, which would make it much harder to detect. --bob rulz 08:54, Mar 27, 2005 (UTC)

Actually, Professor Muller says that it could be hidden behind a cloud or something...


[edit] magnitude

The magnitude estimates don't make sense and are best omitted. Any object between magnitudes 7 and 12 anywhere in the sky would have been discovered a long time ago already (through proper motion surveys or ongoing asteroid searches). And by the way, "at least magnitude 7" is understood to mean 7th magnitude or brighter (ie, 7 or 6 or 5, etc). --Curps 15:45, 2 August 2005 (UTC)

The contention, and I have only Muller somewhat dated word on this, is not that it hasn't been observed, but rather that the distance surveys are incomplete over a significant fraction of the sky (especially far from the plane of the solar system) so that the fact that it is very close has not previously been recognized. It should have said magnitude 7 or dimmer. It is also worth noting that the thing would be moving much slower than asteroids or comets, so most of the surveys designed to see such objects would overlook Nemesis. --Dragons flight 16:57, August 2, 2005 (UTC)
Sorry, but anything of magnitude 7 anywhere in the sky would have been discovered more than a century ago. In astronomical terms, this would be an extremely bright object. Many very slow-moving stars have been discovered through proper motion surveys, for instance Barnard's Star is of magnitude 9.5. Most of the nearest stars to the solar system have been discovered through such proper-motion surveys.
This is incorrect. There are several thousand catalogued red dwarves which have never been parallaxed before. These dwarf stars tend to get shoved aside as small and boring, uninteresting nobodies. However, recently a red dwarf was discovered a little over 7 light years away, and is now the 3rd closest star system to our sun.
The distance to Teegarden's star has been corrected to 12.6 light years. Therefore, if Nemesis is similar (in brightness) to that star and its distance is 1 lightyear, it should be 12.62 = 158.76 times as bright. That results in a magnitude difference of 5.5, or a magnitude of 9.9 for Nemesis. Icek 12:52, 1 December 2006 (UTC)
I can't say exactly what magnitude Nemesis would have to be to remain undiscovered until today, but it would undoubtedly have to be considerably fainter than 12th (probably around 15th magnitude or fainter, given the recent discovery of Teegarden's Star). -- Curps 17:44, 2 August 2005 (UTC)
To be clear, if it exists, it almost certainly is already in the catalogs and has been for a long time, but many stars in the catalogs have never had their distance measured. Of course, I would agree with you that it is mostly likely considerably dimmer. However without someone authoritative source to refer to, we can't really overturn Muller's statement that it is most likely a red dwarf between magnitude 7 and 12 [1]. --Dragons flight 18:35, August 2, 2005 (UTC)
If it exists at all, it's a brown dwarf IMO. If it were an actual star at a distance like that, even a red dwarf, I don't think we would have missed it so far. Even a red dwarf at one light-year is going to be exceptionally bright by red dwarf standards and likely to raise suspicion. (A 7th magnitude red dwarf? If there were such an object, you better believe the first thing I'd do is check it out.) On the other hand, an old brown dwarf at that distance might not be any brighter than a Kuiper Belt object is, and easy to miss.
A red dwarf at 1 light year could easily be 10th or 11th magnitude - probably lower - and there are various ways to potentially hide it. I'm sure that precovery images can find it well, well back, but there are lots of stars that are poorly studied or essentially unstudied. Brown dwarf? Or just planet? Also possible ~ I've heard it suggested that objects as small as mars can create the effect (they can, at least, create the Kuiper cliff). WilyD 14:18, 1 December 2006 (UTC)
I checked with Celestia, running what the brightness of the M9V red dwarf star DENIS 1048-3956 would be at a distance of one light-year. That star, which is probably a good match for what Nemesis would be like, would be magnitude 11.7 at that distance, and there's so many objects at that magnitude that we'd likely not notice it unless we measured its distance. Based on that, I'd say Muller's idea of what Nemesis is, is sound. user: Jsc1973
That assumes that there is a Nemesis, which is speculative to say the least. Note that a brown dwarf would be fainter still. However, Hipparcos is complete down to ~11 mag and parallax of three arcseconds would be obvious in current sky surveys, which routinely go down to 15th magnitude over the entire sky (similar to the case of Teegarden's star), so we have an additional three magnitudes, which push any Nemesis firmly into the L-dwarf category. We have verged into original research. Celestia is either a blessing or a curse. Michaelbusch 04:31, 11 January 2007 (UTC)
I was assuming for the purposes of the check that there is a Nemesis. I had no idea than an M-dwarf so close would be quite that dim. Agree that it doesn't belong in the article though. Can't help but think we won't find it anytime soon if it's a brown dwarf. It would have been cooling for the last 4.5 billion years. Jsc1973 08:10, 11 February 2007 (UTC)
The star(if it exists)I consider is unlikely to be of a magnitude as high as 7 but could be dimmer, the 12th magnitude seems reasonable. Saying that because it hasn't been discovered yet so must be very dim is innacurate many known stars have not had their distance measured as Dragons Flight points out. I also believe it is to be a brown dwarf, an M-type star would be highly unusual to go unnoticed at such close proximity. I guess the WISE mission will tell us for sure. Allywilson 17:30, 14 March 2007 (UTC)
Well, without verifiable sources we can't speculate much, but yeah - there's no way such a thing burns Hydrogen. Deuterium, maybe, but even that seems unlikely. A few Jupiter masses or less, maybe as little as an earth or such ... WilyD 17:34, 14 March 2007 (UTC)

[edit] Death Star

Star Wars came out in 1977 and this article reports that Nemesis was first proposed in 1984. If Star Wars came first, and it was already huge by 1984, how could the Death Star nickname have "fallen out of usage due to its fictional use in the Star Wars universe." --[User:SimonP|SimonP]] 20:53, Jun 13, 2005 (UTC)

You probably need to ask User:L. who is the one that added that material, but if I were to make a random guess, perhaps some people wanted to refer to it as the Death Star and did for a while, but that it never caught on because the public at large had already equated Death Star to Star Wars. --Dragons flight 21:52, Jun 13, 2005 (UTC)


Why does the phrase "Nemesis (Death Star)" refer/link to the Star Wars Space Station? 122.2.111.174 (talk) 10:51, 3 April 2008 (UTC)

I believe the term "dark star" is correct and from what I gather "death star" as part of a conversation concerning Nemesis is a joke. —Preceding unsigned comment added by 12.111.134.2 (talk) 02:13, 13 May 2008 (UTC)
Not for either of our definitions of "Dark star" WilyD 04:39, 13 May 2008 (UTC)

[edit] abrupt outer bound for Kuiper Belt as evidence

The shape of Saturn's rings, the abrupt outer bound for the Kuiper Belt and observations of two nearby stars are offered as possible evidence for the existence of Nemesis. [2]

Said evidence is sketchy at best.Michaelbusch 20:33, 26 September 2006 (UTC)
  • There is certainly a much more widely accepted explaination, anyhow. WilyD 17:08, 24 November 2006 (UTC)

[edit] Discussion regarding competing theory

I have removed all of your changes to the Nemesis (star) article. While the Binary Research Institute proposes the existence of a companion to the sun they do so in a much shallower orbit and do not identify it with Muller's Nemesis (a name that never even appears on their website). Hence their theories don't really belong in the Nemesis article, but perhaps you could start an article about the BRI? Dragons flight 17:33, 21 January 2006 (UTC)

  • I didn't even know they existed until something on Slashdot showed up this morning. They however did cite Muller regarding his comet work. If you feel it all needs to be explained under a new article, that would make some sense.
    • That's actually a weird place to cite Muller since he actually doesn't believe in the "belt of comets", as he generally chalks that result up to observational bias and statistical error in judging the significance of the enhancement. I do think though that any discussion of a companion with ~20 kyr orbit needs to happen in a different article since Muller's Nemesis proposal has a 26 Myr orbit, and hence is a very different object. Dragons flight 18:54, 21 January 2006 (UTC)
      • I'll copy-paste this to Nemesis discussion for future guidance & I or someone else will work on this later. Cwolfsheep 19:40, 21 January 2006 (UTC)
        • It appears from their website that the founders are some form of crypto-danikenites, attempting to link a companion star with ancient mythologies of 'golden ages' and 'gods' from the sky who walked among men. At best, they are pseudo-scientists or creationists, at worst, UFO cargo-cultists. The problem is that this sort of topic is likely to attract many fringe elements due to its tones of chiliasm and millenialism. The 26 million year time frame doesn't meet their ideas of recent "hidden" human history, so they need a shorter orbital period to make it work. If they knew their science, they'd know how relatively easy it would be for a technological civilization to travel a mere 1-1.5 light years (the estimated current distance of Nemesis, according to Muller) via fission or fusion pulse detonation propulsion (aka Project Orion and Daedalus) in 20 years. Entirely attainable. If humanity knew how close the nearest star was (if Nemesis exists), the space program would become a major global priority, so there are also political undertones to this topic as well.

[edit] Page name

Disambiguation should be kept as simple as is necessary to distinguish the topic from related topics with which it might be confused. As far as I know there are no other stars (real or hypothetical) that bear the name Nemesis, and hence labelling it (hypothetical star) rather than (star) is unnecessary. Dragons flight 20:10, 26 September 2006 (UTC)

Perhaps. It must be distinguished from the asteroid, however.

[edit] Requested move

Nemesis (hypothetical star) → Nemesis (star) – As above, parenthetical names should be as simple as is necessary to avoid existing conflicts. They are not intended as a form of categorization. In this case, (star) is more than sufficient to the distinguish the topic, and Nemesis (star) is the title it has had since its inception. I tried to move it back, but another user reverted, so I am listing this at RM. Dragons flight 18:54, 27 September 2006 (UTC)

[edit] Survey

Add "* Support" or "* Oppose" followed by an optional one-sentence explanation, then sign your opinion with ~~~~

[edit] Discussion

Add any additional comments

I disagree with both names. The hypothesis is for Nemesis to be a brown dwarf. By definition, a brown dwarf is substellar and should not be called a "star." By analogy, a dwarf planet is not a planet. Consider the name "Nemesis (hypothesis)" or something like that.Teply (talk) 02:08, 27 November 2007 (UTC)

[edit] Some more info

Can there be more information added about this hypothesis' reception by the broader astonomical community, and any objection to the hypothesis be added. Basejumper2 21:51, 29 October 2007 (UTC)