Re: WIRE wildly flashing
Jim Varney (jamesv@softcom.net)
Sun, 7 Mar 1999 11:51:33 -0800
On 7 Mar 99, Ron Dantowitz wrote:
> >Just south of the zenith I think I counted 20 flashes in 9.63 sec, for a
> >period of 0.49 seconds. There is uncertainty in the count, it was
> >difficult to keep up. News accounts report a tumble rate of 1 second --
> >did a see a half period?
> >
> >If visual appearances mean anything I don't think they are going to
regain
> >control of this one.
>
> Especially if the flashes are getting more rapid! I measured a 3.233
second
> repeated flash period on 5 March 99 at 23:45 UTC. Very accurate... so if
it
> is faster now... looks REAL bad.
Ron,
There may or may not be a correlation between the apparent tumble rates
that we observed and the actual tumble rate. The relationship between sun-
sat-observer, possibly multiple spin axes, and a bunch of different
reflecting surfaces can get pretty complicated. Just in my observation
alone there was a rapid increase in the apparent flash rate over the span
of one minute.
It's possible there was more outgassing of the onboard hydrogen between our
two observations. I can't rule that out. But if I had to guess it's
because I'm lucky to have perfect zenith passes at close range, and I'm
seeing a lot of secondary flashes off of different surfaces.
If the weather holds I'm looking forward to another very good pass tonight.
It's quite a sparkler here!
-- Jim
__________________________________________________________
Jim Varney
Member, Sacramento Valley Astronomical Society
Sacramento Iridiums www.softcom.net/users/jamesv/index.htm