(meteorobs) The Aurigids in 2007: Jenniskens expects a ZHR of 400+

[Petrus Jenniskens]

Hello Joe,

I have returned from travel in Europe and am catching up
on my e-mail. I suspect your question was answered 
already,
but just in case: you are right about the time of Full 
Moon.
September 4 (02:32 UT) is actually the time of Last 
Quarter. That was
sloppy of me. Point is that the Moon is bad for visual 
observations,
but not too bad given that we are a few days away from 
full
Moon and the shower is expected to be rich in -1 to +1 
magnitude
meteors.

As regards to the ~2500 years, Jeremie back
integrated the orbit and found that the previous return of 
the
comet was in 82 BC. The orbital period is affected by 
planetary
perturbations and changes somewhat from one return to the
next.

-Peter


---
On Sat, 19 Aug 2006 15:23:23 EDT
  Skywayinc at aol.com wrote:
> In a message dated 8/19/06 11:26:15 AM Eastern Daylight 
>Time, 
> verfl.meteors at seznam.cz writes:
> 
>> on http://astro.cas.cz/nuncius/ you can find the IAU's 
>>GA daily newspaper
>> (okay, that's a bit of  self-propagation, i'm one of the 
>>editors:) and in
>> the 6th issue down there look on the first page - there 
>>is an article from
>> Dr. Jenniskens and Dr. Vaubaillon, approximately equal 
>>to Dr. Jenniskens'
>> yesterday's annoucement.  He also speaks there about his 
>>coming book about
>> meteor showers which shall be available somewhere in 
>>september, I think, and
>> which can probably provide more information on the 
>>topic. 
> Jan -- 
> 
> A very interesting article, with very exciting 
>prospects!  
> 
> I would, however, like to point out a correction, 
>followed by a question, 
> which perhaps Dr. Jenniskens, Jeremie Vaubaillon or Esko 
>Lyytinen might be able 
> to answer.  
> 
>First . . . the correction.  The article states that next 
>year's Aurigid 
> shower will take place three days before a Full Moon 
>occuring @ 02:32 UT on 
> September 4.  In reality, the shower will peak nearly 
>four days AFTER a Full Moon 
> occurring @10:35 UT on August 28. 
> 
> As for the question . . . the orbital period being 
>quoted for Comet Kiess is 
> given as ~2,000-years.  However, most reference books 
>(such as Gary Kronk's 
> Comets -- A Descriptive Catalog) indicate that the 
>period is closer to 2,500 
> years.  I plugged the orbital elements for comet Kiess 
>into an orbital simulator 
> on my hard drive (with e = 0.996296) and my computer 
>spit out an orbital 
> period of 2508.55 years. 
> 
> Then again . . . what's ~500 years among friends?
> :)
> -- joe rao
> 
>