[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Does the earth wobble?

On Mon, 3 Jul 1995, James Shields wrote:

> >Of course the earth wobbles, but only by a degree or so either
> >way.  The wobbling is on such a short cycle that it is irrelevant
> >to dino extinction.
> First, may I wish all you Americans (and, of course, all free people)
> Independence Day Greetings.

Why thank you!...there are some things that could use a tune up, but 
after 219 years, most of it still seems to work reasonably well...

> Now, I have a question. How is "wobble" measured? I expect that it is so
> lasting millions of years and going through a larger angle? Obviously a
> longer cycle would be harder to detect.

There are a number of cycles that the earth goes through that were 
discussed here recently. Look through your digest/list mail from the past 
week or two under the subject header of "Milankovich cycles". There was 
one particular posting(I forget by who) which listed out all of them 
including the Sun's orbit around the Milky Way.
> I don't think wobble is likely to be a cause of extinction. My point is that
> if the tilt of the Earth was different during the mesozoic it would have a
> seasons would be much less. We know the earth was much warmer then, and this
> could offer a partial explanation why.

In your hemisphere perhaps, but not everywhere. You would still have to 
account for the hemiphere/pole that was inclined opposite to the direction 
that your favorable inclination was it.  
> On the other hand, if I am flogging a dead horse, please let me know.
Its been covered here recently, but even at that, its still got its skin 
intact and rigor hasn't set in yet, at least not in comparision to the 
cladistics/impact debates which are dead,buried,replaced and showing 
signs of compression :)