If you're after high-performance free astro software, you can't go past Xephem. You can get it from
clearskyinstitute.com. But it is not recommended for the trigger happy Windows user. Xephem is not a toy!
It is essentially UNIX software (includes MacOS/Linux) but also runs on Windows under Cygwin. If you're a Windows user who never heard of Cygwin, you probably should not bother... but you might want to check Cygwin out anyway just to see what you're missing.
One of the great things about Xephem is the library of objects available. It's pretty easy to download and work with all kinds of celestial objects, from space junk to asteroids to faint (~ mag 16) stars.
For semi-braindead look at what's up I prefer
xplns. The program is very fast and simple but you can still select the type of projection and what DSOs you want up to what magnitude.
Xephem tells me that Mars is up and visible and I have a little refractor waiting for me outside, so bye for now.