Hi folks,
Martin, about getting dates of aphelion/perihelion for planets and
dates of crossing the ecliptic: sorry, there is no really straightforward
way of doing this. The best you can do is to run an ephemeris for an
object, with the 'distance from sun' (r) field included; then you can
look for a maximum (aphelion) or minimum (perihelion) value. You can
then be confident that the next such event occurs half an orbit later,
and run an ephemeris for that time.
For ecliptic crossing, you can turn the ecliptic on (in Display...
Ticks, Grids, Etc.), then start up Animation and track the object
until it crosses the ecliptic.
Truman, about adding a star, such as a nova, to Guide's database:
this should probably be done as a user-added object. For an example
of this, I'd recommend downloading the dataset available at:
http://www.projectpluto.com/extras.htm#jmi_iii
As is noted there, this dataset is intended to show the alignment
stars for the JMI-III digital setting circles. However, there's no
reason you can't edit the data file, JMI3.DAT, and clean out the
existing stars and put in your own. You can then edit JMI3.TDF to
insert your own comments (so that, say, "My list of novae" appears
instead of "JMI-III alignment star").
My thanks to those who replied to Jean-Paul Verrot's post asking
about how to import DSS images into Guide. I started writing a reply
in French, but my use of the language was pretty awful. So I was
pleased to see replies from others.
James' suggestion that we attempt English versions of French (and
other) language posts is probably the way to go. We don't get many
such posts (which is a little surprising, considering the percentage
of Guide users in non-English speaking countries.) There seems to be
little danger that we'll be swamped with non-English comments.
-- Bill