This is a free planetarium software set for your PC. Once installed it shows pictorially the sky at night. Starts, Planets, Nebulae and Galaxies can be seen and located in the sky making observation easier.
Download the software from :- http://www.stellarium.org/
Cartes du Ciel.
This program enables you to draw sky charts, making use of the data in 16 catalogs of stars and nebulae. In addition the position of planets, asteroids and comets are shown.
The purpose of this program is to prepare different sky maps for a particular observation. The program makes this celestial atlas more complete than a conventional planetarium.
Download the software from :- http://sourceforge.net/projects/skychart/