Re: Guide and 1999 KW4 Observation

j.van.gijsen@inter.nl.net May 31, 2001

Hi Guides,

On may 30, round 02 am I had a change to get a series of (not to bad)
CCD images of 1999 KW4. Sky was not totallty cloudless, and it was a
little foggy. In the 4" 500mm spotting scope I used star diameters
were some 25" (or worse) in the pics.
First results were simular to Trumans and Larry's. In terms they use:
the actual asteroid was 5 min ahead (relative to the closest
approach in arcdistance and about 40" off line.
I added one pic as in Image to guide using charon and found
a difference between calculated and real position:
1.533' distance, PA 312.5 RA offset 68.87" and Dec offset
60.95". (error margins ignored, my guess is about 10" in RA and Dec).
Brigthness given by guide: 12.2/12.3 from charon a got 12.1 to 12.6
on the 6 best pics a used. So first results are: good match !
It'll take me a couple of evenings to get the best out of the images,
but it was was great to see the asteroid really step ahead every 30
sec. One of the next candidates is 4660 Nereus (not 4661 ;-))

Clear skies.
Jan

(Just got myself a 8" LX200 after using a German EQ mount for 15
years. I'm affraid it'll take a couple of month to get used to it)







--- In guide-user@y..., Truman P Kohman <tk11+@a...> wrote:
> Excerpts from mail: 30-May-101 [guide-user] Change Star trail
overlay by
> "Larry Wood" <chukwood@t...>:
> > The orbital elements I got from the MPC site must have been a bit
> dated because
> > the Asteroid was about 5 minutes (time wise) ahead of and 20 to 30
> arc-seconds
> > to the right of its position as plotted in Guide.
> Guide Users/Observers,
> The night of May 26 started out clear, and then clouds rolled
in,
> but fortunately there were occasional breaks through which from my
back
> yard in Mount Lebanon, near Pittsburgh, I could get a good polar
> alignment on my Celestron-8 and look for asteroids. After first
> revisiting 532 Herculina, using the Guide tracking chart I had
prepared
> and posted on this month's Amateur Astronomers Association of
Pittsburgh
> Web site (http://www.3ap.org => S.I.G. => Asteroids and Comets), I
then
> I looked for the NEO 1999 KW4, ~5 degrees S of Alpha Herculis, using
> chart 1000KW4-re-e on the same Web site. At 1:30 EDT (now May 27) I
> noticed that a pair of stars I had seen several minutes earlier had
> changed their orientation, and very shortly I was able to identify
the
> fast-moving asteroid. It was not far from its predicted magnitude
of
> 10.7. I followed it for a half hour as it glided silently through a
> field of 7th- to 12th-magnitude stars. I called my wife Jane out,
and
> she too saw it moving.
> The next morning it was raining. I prepared a new chart at
Level 7
> (2 degrees) and plotted my observations on it. The actual track was
> about 1' above (NE) of the plotted track, and the asteroid was ~4
> minutes (~3') ahead of the plotted positions. I think that this is
> excellent agreement, and testimony to the accuracy of Guide.
> Truman
>
> Truman P. Kohman, Departments of Chemistry and Physics
> Carnegie-Mellon University, Pittsburgh, PA 15213 USA
> Phone: 412/268-8865, 412/561-8343 Fax: 412/681-0648
> Internet - ASCII messages and documents: tk11+@a...
> For images and coded attachments: tpkohman@y...