Re: RGO, Lageos 2, SeeSat-L

Bart De Pontieu (
Thu, 21 Aug 1997 13:53:10 +0200 (MET DST)

On Wed, 20 Aug 1997 Craig Cholar wrote:

> I asked a question about whether obs should be sent to the RGO
> (Royal Greenwich Observatory), as suggested on the VSOHP website.
> I got a private reply from the UK, and excerpt of which follows...
> > Don't bother ... The only work done now is laser work and
> > no optical analysis is carried out on ANY visual work by
> > any analyst anywhere in the UK. As far as I am concerned,
> > it is a waste of time to send obs to RGO, and other visual
> > - far more prolific observers than I - also agree.
> I'll not reveal the name of individual, since the reply was private.
> Other parts of the reply that I've omitted indicated that the author
> has had extensive dealings with the RGO.
> I'll leave it to others to decide whether or not the references
> to the Royal Greenwich Observatory should stay on the VSOHP website.
> The specific page in question, for the curious:

Since I am the author of that page, I guess I better reply...
The text of posn_measure.html is actually a latex2html version of the
'Introduction to satellite observing' brochure of the Belgian Working
Group Satellites. At that time I had lots of experience with flash period
timings, but not with positional measurements. So, I asked an experienced
observer in the UK with good contacts to RGO what I should include in the
brochure, basically offering them to write a few pages on their activities
and what they expect from observers. In the end I was just told my very
crude text was sufficient and that observations were still welcome at RGO.
So that's why that page is a bit limited in scope, and why it has RGO's
address on it. If the people with good contacts to RGO confirm what you
write, Craig, I see no reason to keep RGO mentioned in that page. And it
is probably a good idea if one of the SeeSat-L experts on positional
measurements do a re-write of that page. Anyone feeling an urge, should
contact Neil, Jeff or me. I can't remember who was supposed to take care
of that section in the apparently dormant FAQ-project. Sue, any clue? :-)

> I've yet to hear from anyone who is sending obs to GRO. If you 
> are, and they are being used, please let us know.  

At the Space Debris session of the COSPAR conference in Birmingham last
year, I briefly talked with some of the analysts who used to publish
articles about visual positional observations. [up to a few years ago,
one could quite regularly see articles in, if I remember correctly,
Astrophys. Space Sci. or Planet. Space Sci. - check for articles by e.g.
Dr. Swinerd - ]. It seems most of them have now moved on to more rewarding
topics, such as space debris.
Given the response to my talk about flash period measurements of
space debris, I'm not surprised people move on to space debris research.
It is a very new and rapidly evolving field of research in which there's
lots of enthousiasm and room for new ideas and techniques.

> I believe a
> few months ago there was brief mention in Seesat-L that precise
> visual obs of some satellites such as LAGEOS were being requested
> by some organization, but I can't recall the details.  I'll do an
> archive search to refresh my memory.

At COSPAR I was contacted by researchers who use Lageos 2 data. They were
interested in historical (and current) measurements of the flash period of
Lageos 2, in order to try to model the torques acting on Lageos 2.
I think that was the message you saw on SeeSat-L, Craig.

Speaking of SeeSat-L, unfortunately I will be absent from tomorrow onwards
until September 22, with little or no e-mail access. If you have problems
with SeeSat-L, contact Neil Clifford at

For those who have read all the way down to this paragraph: I will be on
a business trip to Washington DC between September 15 and 21. Are any
SeeSat-L ers of that general area interested in meeting up?

And, please, try to stay on topic: radio observations, general space
flight questions/answers, etc... are not really what SeeSat-L is there


Bart De Pontieu    --     --   SeeSat-Ladministrator
solar physicist at Max-Planck-Institute for extraterrestrial Physics, Garching
   "Phew, for a minute there I lost myself" -- Radiohead, "Karma Police"