Redshift brings a planetarium to your Mac desktop. After you enter your home's location, you can view the sky as it will appear above your backyard later in the night.
Redshift - Astronomy
Redshift makes it easy to identify planets, stars, comets, galaxies, nebula, and other space objects. It also goes a step further, and models nearby parts of the galaxy in 3D, letting you take a scenic flight around the solar system or deep sky objects. You may also want to try entering the orbit around an object.
Besides the fun of the 3D models, Redshift contains comprehensive data about all of the items in its database, including 70,000 deep sky objects, 10,000 minor planets, 250 well-known comets, all major and minor inhabitants of our solar system, and a catalog of stars that currently exceeds 2,500,000 entries.
Redshift - Astronomy is $18.99.