With regard to the above written “arc-shaped line curving upward toward the left, or east” this arc-shaped imaginary line is in effect known as the ecliptic. The ecliptic in reality is the orbital path of the Earth around the Sun. However from our perspective we see the ecliptic as the apparent path the Sun follows against the stars in the background. It is the ecliptic that defines the constellations of the zodiac for example. Somewhere within a few degrees on either side of the ecliptic are where the 8 planets, Mercury – Neptune, are located as we view them from Earth. Our Moon also follows a monthly path that takes it above and below the ecliptic.
Click here to go to the Qué tal in the Current Skies web site for more observing information.