SkyMap 6.4

Matson, Robert (
Thu, 19 Aug 1999 10:20:00 -0700

Hi All,

I wanted to thank Ed Cannon for posting SkyMap 6.4 and its associated
files at his web site.  I uploaded them to the ftp
site, but for some reason they have yet to appear.  I sent a message
to Neil about it, but he may be on vacation -- it is summertime in
Europe after all.

Anyway, I thought it would be appropriate for me to mention some of
the additions in 6.4.  The most important new feature is support for
the Tycho star catalogue (1 million + stars).  For those who haven't
found them already by accident, they are named TYCHO00.ZIP through
TYCHO23.ZIP (one file for each hour of right ascension), and are
located at:

Originally I only planned to make TYCHO available to registered
users; however, I decided on a compromise.  Unregistered users can
access a single TYCHO file at a time; registered users will have
simultaneous access to the entire catalogue.  In practice, this
is not much of a hinder for unregistered users since the only
time it makes sense to use Tycho over Hipparcos is for narrow
fields of view with stars dimmer than 9th magnitude.  (Of course,
viewing near the poles doesn't work too well with only 1-hour
right ascension wedges!)

I have also created Hipparcos and Henry Draper catalogue index files
of the form TYCHOxx.HP and TYCHOxx.HD respectively.  They can also
be found at the above ftp address, zipped as TYCHO_HP.ZIP and

In addition to Tycho, I've also added asteroids to SkyMap.
ASTEROID.BIN (zipped in ASTEROID.ZIP) contains the necessary
orbital ephemerides for all known earth-crossing asteroids, plus
all asteroids that can become as bright as magnitude +12.  (There
were 964 as of a month ago).  Registered users can receive a
file containing info for over 52,000 asteroids.

There are a number of bug fixes and a few minor new features that
are explained in SKY64.NEW.  Enjoy everyone!