From: Milton Aupperle <milton@outcastsoft.com>

Date: November 10, 2011 10:08:10 AM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Re: Asteroid 2005 YU55 observations?

Hi Tim;

Very cool and thanks for sharing.

I had planned on doing an "ambush"  like you described (set up on a field with a good guide star) and then record it's flight through my FOV.

But the full moon would really make it tough to see and I had enough uncertainty in position, that I think it would not have dashed through my FOV. With the CCD, I was just barely making out Mag 12 to 13 stars against the moon lit sky.

On a side note, I'm working on an update for AVT which fixes some issues with AVT Cameras (they do not deliver 16 bit video in proper Big Endian format and I enabled the Auto Exposure). Version 7.02.00  has the ability to do Astrometric measurements for moving objects over time from a movie.

I tested it out on the JPL ephemerides for the Asteroid Euphrosyne on October 27. My calculated position (using 3 reference stars) was within 0.6 arc seconds ( < 0.7 pixels) to the JPL RA and Dec coordinates  for the 6 hours I recorded it.

This should work pretty well for getting positions on comets too.

TTYL..

Milton Aupperle

On 10-Nov-11, at 8:10 AM, doobisary wrote:

Hi Milton:

Well, I did manage to SEE it!  I started looking about 10 minutes before it crossed onto the S&T hi res finder chart.  Star-hopped the whole way in Los Angeles 3rd magnitude skies with a nearly full moon!

I made sure I had the right star fields and started the hunt!  It took me about a half hour after the 'roid crossed onto the chart to find it, though.  But once I did, I was able to track it visually for about 45 minutes.  Man, that sucker was MOVIN'!  Faint, too.  I don't think I would have seen it if it was much dimmer.  I had to use averted vision to relocate it after losing it about 5 times over the 45 minutes.

A luthier friend of mine from down the street came over with a couple of barley sodas and watched it with me.  It was fun showing such an obscure special-interest subject to a non-astronomer and seeing his reaction to it.

It was a good evening.  When we finally lost track of the asteroid, I didn't make any attempt to locate it again, because it was already pretty far off the hi resolution chart by that point.

I would never have found it on the ccd, though.  Not unless I'd star-hopped into position first and ambushed the asteroid as it screamed through the field.  I had thought about trying that strategy last night or tonight, but a storm system is coming through and I don't expect to see the sky until Sunday at the earliest.

-Tim.