Re: [guide-user] Re: Charon

Bill J Gray Nov 3, 2009

Hi Chris,

Hmmm... perhaps the best way to handle that problem
is as follows.

Start up Guide, and hit ':'. This will cause Guide
to display a chart of the world with the nearest solar
eclipse.

Zoom in on the Canary Islands. Use Extras... Toggle
User-Added Datasets. Select "MPC Stations"; turn it
On, with labels showing.

If you're lucky, your remote observatory will show
up; right-click on the symbol shown for it, and you'll
get the name and MPC three-character code for it.

If not, right-click on the nearest observatory,
and use its code for the nonce. That's probably a
good way to start out; if you use that nearest code
and still have problems, it'll be time to dig deeper
into why those problems are happening.

If you really want a code of your own, there are
two routes. One is to submit data to MPC and they'll
assign you a code. Or, you can (temporarily) make
up your own three-character code. To do this, edit
the file 'obscodes.htm' and look for the line
corresponding to the nearest existing MPC station.
It might look like this:

J24 343.557190.881661+0.470499Observatorio Altamira

This says that (J24) Observatorio Altamira is
at East longitude 343.55719 (known to most of us as
West longitude 16.44281), at parallax constants
rho_cos_phi .881661, rho_sin_phi +.470499. Converting
parallax constants to and from latitude and altitude
above sea level is slightly unpleasant and probably
not really justified for what we're doing here.
Instead, just take the line for the nearest observatory
and change (say) J24 to, say, ZZZ. ("Official" MPC
codes don't start with Z; use ZZZ, and you can avoid
collision with any "real" MPC code.) Change the
observatory name as well, of course. Then add your
newly-created line to 'stations.txt'.

-- Bill