Re: Sattelite Track or Meteor?

[Tom Droege <tdroege@veriomail.com>]

I don't want to make a big deal out of this.  I was just checking to see if 
anyone is interested in satellite track pictures in two filters.  Herb 
Johnson proposes that it is brighter in the infra red because it is being 
lit by light that has passed through a lot of atmosphere.  This sounds like 
a good explanation to me.

The peak to peak amplitude is about 35 arc seconds.  If we assume it is at 
150 miles altitude, then this makes the rocket booster 127 feet long - or 
properly this is the component of the tumble.  Not unreasonable.  I am at:
N 41 Deg. 49.602',  W 88 Deg. 18.757'  by my trusty GPS receiver.   I was 
off in my estimate of the period.  It is about 12 pixels or 166 tumbles in 
going through 4 degrees.

At 150 miles we are not likely to be able to get a distance 
measurement.  But if Andrew can get 0.1 arc second, then there is a chance.

The track passed about 1 1/2 degree W of 34 alpha Aq.  and about 2 minutes 
E of 28 Aq.  Track is very slightly E of N.

This just for fun.  Our government must have wonderful cameras tracking 
such things.  Hmmm!  I wonder how they are at making variable star 
measurements?

Tom Droege

At 11:37 AM 11/6/00 +1030, you wrote:
>At 23:32 5/11/00 , you wrote:
> >The first frame of the evening taken with TOM had a prominent N-S satellite
> >track.  The track was much brighter in I than in V, and was tumbling
> >rapidly.  It was taken at 7:39 PM CST on 4 November 2000 with the telescope
> >looking roughly 1 degree N and 10 degrees West.  Anyone know of a tumbling
> >object going over at that time?  Since it is much brighter in the IR, could
> >it be a meteor?  Very tight cork screw image.  Possibly 100 turns in going
> >across the frame.
>Tom, give me your position (to 1 arc minute quite good enough,
>though to 0.1 degree would probably do), and I will check against the most 
>comprehensive list of objects in orbit available to the general public.
>
>
> >
> >Since TOM is a stereo pair, one should be able to extract the altitude of
> >the object if it is below 50 miles or so.
>Since most satellites are at heights above 130 miles stereo images
>would work.
>The largest part of the fast spinning population are because Russians
>  spin their upper stage rockets after  payload release to
>avoid collisions. This includes the russian launches used to put up
>the globalstar MEO comsat satellite constellation.
>This results in sub second tumble periods, that are hard to
>measure by eye and stopwatch, as they happen too quickly.
>The period increases with time as eddy current damping
>takes place.
>Tony Beresford
>34.9638S,138.6333E