Sometimes you don’t want to buy a book, you want to get a free app. We have thousands of free books available for Android Phones and Tablets.
Click on the title of this section to expand the list and show you every app in our system!
Copernican Orrery« Books & Reference « Downloads
|Updated||December 31, 2012|
|Category||Books & Reference|
A Copernican-style Orrery showing the positions of the 8 planets and their primary moons as well as our moon’s phase.
The Orrery is a model of the solar system as view from celestial north, and orientated
such that solstices occur when the earth is due-north (top, winter solstice) or
south (bottom, summer solstice) and the equinoxes are east (right, autumnal equinox)
and west (left, vernal equinox). All orbits are assumed to be perfect circles.
The position of the Earth and Moon are fairly accurate, as are their orbits. The remaining planets positions are approximate, but close enough considering the size of the typical phone or tablet screen. The starting positions of the moons other than that of the Earth is not accurate. The orbital periods of all planets and moons is accurate relative to the other planets and moons.
This app should be considered simply something fun to look at, but not anything to be taken too seriously.
- Fifty Shades of Grey
- One Piece Theme GO Launcher EX
- Sasuke Theme GO Launcher EX
- FastDic - Persian Dictionary
- The Kissing Booth
- Twilight Book
- Subway Surfers Tips&Tricks
- Ponniyin Selvan (Kalki) Tamil
- Phum Dictionary (Khmer 3 in 1)
- Wikipedia for Android
- 50 Fifty Shades Freed
- English Slang Dictionary
- Baidu Translate-EN CH JP TH RU