Sloan Digital Sky Survey
SkyServer DR12  
Not logged in Login Help
 

DR12 Projects
 Basic
     - Solar System
     - Scavenger Hunt
     - The Universe
     - Asteroids
     - Types of Stars
     - Color
     - Galaxies
 Advanced
 Research Challenges
 For Kids
 User Activities
 Games and Contests
 Links to Others

Solar System
 Coordinates
 Mapping
 Earth Sun and Seasons
The Sun's Perspective
A NASA image of the Sun

The Sun

Explore 2. Now, try taking the Sun's perspective. Imagine the Sun is at the center of your model, instead of the Earth. That is a more realistic perspective, because the asteroids really orbit the Sun rather than the Earth.

Of course, the Earth orbits the Sun also. On September 22nd of every year, the Earth is at about RA = 0, Dec = 0. Draw a small + (plus sign) mark at that point with permanent marker and label is "Sept. 22nd".

Now, rotate the model so that the ecliptic (the circle of asteroids and planets, which includes Earth) appears perfectly horizontal. Imagine that you are standing on the Sun (at the center of the cylinder), looking out at the Earth. You can see light rays going from the Sun out to the Earth. At what angle do these light rays hit the cylinder? (Assume that an angle of zero degrees means the rays hit straight up and down.)

Previous page: Earth, Sun, and Seasons Next page: The seasons