What is the current staus of theories on this?
Summary of what I recall:
It’s been several years since I’ve heard of any new info. Does any of the above still hold water?
I recall reading a book by an astronomer named Miller about it. I don’t think it’s taken very seriously outside of a few (or maybe just one?) astronomer(s).
… Just found the book I read: it’s this one. With a title like Nemesis: The Death Star, how could I avoid it.
It was some time ago, but I seem to recall being unconvinced by the book. I don’t recall much of it, and indeed never knew much about it in the first place! So I’m sorry I can’t be more helpful.
This book apparently also discusses the hypothesis.
The Bad Astronomer has his own collection of Planet X articles.
Planet X and Nemesis are two entirely different objects. Nemesis, at least, was proposed by real scientists to explain real scientific events. Nevertheless, there is still little to no evidence for it.
Space.com has a good and recent (2001) article detailing where the Nemesis controversy stands.
I think Nemesis has very little credibility. For one, it’s based on a supposed 26 million year cycle in mass extinctions. From what I have read, there is no (or very little) evidence for such a cycle. I need to look into it more, but from what I have read this is scanty stuff to base a theory on.
I also read the journal articles about comets indicating a planetary mass somewhere way far out in the solar system. I thought the papers were not supported well either. The evidence they used was pretty slim, and I was really skeptical about how they picked it (they threw out some comets that went against their theory, and it wasn’t clear to me that doing so was supported).
There may very well be a large mass out there, way beyond Pluto. But so far there is no direct evidence for it, and at best marginal direct evidence. Until something more solid comes along, I put Nemesis into the “highly dubious” category.
I think Nemesis has very little credibility. For one, it’s based on a supposed 26 million year cycle in mass extinctions. From what I have read, there is no (or very little) evidence for such a cycle. I need to look into it more, but from what I have read this is scanty stuff to base a theory on.
I also read the journal articles about comets indicating a planetary mass somewhere way far out in the solar system. I thought the papers were not supported well either. The evidence they used was pretty slim, and I was really skeptical about how they picked it (they threw out some comets that went against their theory, and it wasn’t clear to me that doing so was supported).
There may very well be a large mass out there, way beyond Pluto. But so far there is no direct evidence for it, and at best marginal indirect evidence. Until something more solid comes along, I put Nemesis into the “highly dubious” category.
If the BA feels so strongly about it he feels he has to repeat it that’s good enough for me!
How seriously can you take any theory that’s based on a forty-year-old episode of the Avengers?
I’ve not read it, but David Raup’s book seems to be the standard overview of on the whole controversy.
As the BA implies, Nemesius can hardly be called a theory. It’s numerology, and bad numerology at that. It’s a big stretch to make the 26 million year cycle fit, and even then there are anomilies.
Reminds me of Bode’s “law” of planetary distances. The numbers are a bit off, there’s nothing but rubble where a planet should be, and Pluto doesn’t fit at all.
Close counts in dancing, but not in science.