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Re: (meteorobs) No outburst from Ursids in 2001?

I should leave this question go, but since I worked in a group some forty years
ago which was called the "conics" group whose function was to search for
multiplanetary space missions, I can't resist.  Further my ignorant answer might
be better since one that asks the question has not been too familiar with the
jargon.
    First; an anomaly is an angle.  To be more specific the angle made by a
planetary type body between its periapsis passage and some specific time later.
That is the "true anomaly". It sounds to me like a very archaic name left over
from the ancients.
    Second: If you take two Pi (the angular radians traveled in a complete circle)
and divide it by the period of the body in its orbit you have the average angular
speed or mean angular speed "n".
    Third; If you use this mean speed to calculate the position ( anomaly ) of the
body in its orbit you will have the "mean anomaly" M, i.e. n times time since
periapsis passage.  It is not the true anomaly but is useful in subtle ways
involving more geometry than I can illustrate on the computer. For near circular
orbits it is certainly close to the true anomaly. It sort of assume a circular
orbit.
    Fourth;  I don't have the slightest idea what the "mean anomaly factor fM"
is.  But I hope the above description will help you understand any explanation
that more learned people will give you.




Francisco Ocaņa wrote:

> Hi!
>
> Can anyone to explain what the mean anomaly factor means?
>
> Thanks,
>
> Francisco Ocaņa
>
> >
> >
> > Actually an encounter with a trailet from 1392 was found. The encounter is
> > at about rD-rE=0.001au, which is a relative close encounter, considering the
> > trail age. It appears however that the trailet has near the encounter, the
> > very small mean anomaly factor (fM) of about 0.0002. A comparison with the
> > 2000 encouter is difficult because of quite different local properties of
> > the two trailets.
> >
> The archive and Web site for our list is at http://www.meteorobs.org
> If you are interested in complete links on the 2001 LEONIDS, see:
> http://www.meteorobs.org/storms.html
> To stop getting email from the 'meteorobs' list, use the Web form at:
> http://www.meteorobs.org/subscribe.html



The archive and Web site for our list is at http://www.meteorobs.org
If you are interested in complete links on the 2001 LEONIDS, see:
http://www.meteorobs.org/storms.html
To stop getting email from the 'meteorobs' list, use the Web form at:
http://www.meteorobs.org/subscribe.html
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