A device showing the view from the plane of the horizon has around it rings, showing the Tropics, the meridian points and declination, and the ecliptic. — Image by © Royalty-Free/Corbis
A device showing the view from the plane of the horizon has around it rings, showing the Tropics, the meridian points and declination, and the ecliptic. — Image by © Royalty-Free/Corbis