1. Motion
Motion is referred to as either
Real or Apparent.

2. Motion
Does these pictures show
real motion or apparent motion?

3. Motion
Does these pictures show
real motion or apparent motion?

4. Motion
Does these pictures show
real motion or apparent motion?

5. Motion
Apparent motion – what we see in the night sky.
Does not always represent how the observed
object is actually moving.
Real motion – How an object is actually moving.

6. Brightness
The magnitude of an object's brightness can be
referred to as either
Absolute or Apparent.

7. Brightness
(Temperature)

8. Brightness
Apparent magnitude ranks stars by how bright
they look from Earth.
The brightest star (Sol) is -27, and the dimmest star
is 36.

9. Brightness
Absolute magnitude ranks stars by how bright
they would look if they were all equal distances
(33 ly) away from Earth.
The brightest star is -13, and the dimmest star is 15
(Temperature)