Tuesday, July 28, 2009

Star Chart Software: Cartes du Ciel

Question: What good start chart software is out there?

An answer: Cartes du Ciel.

It covers all of the basics. You can set the sky for a particular location and time, navigate around, zoom in and out, pick different projections, change the appearance, add and subtract features (like constellation boundaries or the Milky Way), and print charts. You can even control a GOTO telescope with it.

You can change from the colorful star representation to black stars on white (though the dim stars are a bit too small pixel-wise and hard to see). As you zoom in, more stars appear and that feature works well.

A huge collection of deep sky objects are indicated. Most importantly, you can download and add additional catalogues so that you get to a huge number of objects, down to those probably beyond your instrument.

And it's completely free.

The first thing I wish was different is that the program runs on Windows only. That's a disadvantage which I think will grow over time.

The next thing I missed is a feature of other similar programs: when you zoom into a deep sky object, the symbol turns into an actual image of the object so you can see what it looks like (and zoom into the image further). Yeah, this isn't really a property of star charts, but just something that I find I actually expect. I think you may be able to add this to the program yourself, but I'm not sure.

However, if you want that feature, just use Google Sky. Google Sky doesn't work great as a replacement for star charts (IMHO), but it's fun to look at the pictures.

So, I think Cartes du Ciel can act as a replacement for my SC01 and SC02 Sky Publishing charts, Norton's, Tiron 2000.0 or Becvar, and even Uranometria. You can either print ad hoc charts (I haven't tried this, though) or take a laptop to the telescope.