1. Goal: To understand how objects move in the night sky over any time span, and what we can discover from that.
Objectives:
To be familiar with Basic Sky terms.
To learn about movements in the sky during 1 night.
To learn about movements in the sky during the year.
To learn about movements in the sky over thousands of years .
To understand what we can use these movements for.

2. What can you find in the night sky?

3. What can you find in the night sky?
Stars (Constellations)
Galaxies
Planets
Satellites (man made)
The Moon
Asteroids
Comets
Meteors
Aurorae
Nebulae

4. Motions over 1 night.
Most objects in the night sky (with the exception of the moon) move 15 degrees per hour in a circle around the null point.
Image courtesy of Astronomy Picture of the Day 12/1/1996

6. Motions over the course of a year
Stars stay fixed to the Celestial Sphere
The moon moves around the Sphere once per month (we will cover this more later).
The planets “wander” through the Celestial Sphere also, along the Ecliptic Plane.
Most of the time they move from right to left through the Celestial Sphere (also known as “prograde”) along the . However, sometimes they turn and move in the “retrograde” direction.

8. Constellations Patterns
Can be used as a guide to objects you cannot see with your naked eye

10. Southern Hemisphere

11. Motion over 1 year, the sun and stars.
The sun every year moves 1 full circle along the Ecliptic Plane. (image below courtesy of

12. Side effect of the sun’s movement:
At different times of the year you see different stars. (image below courtesy of

13. Conclusion
We have learned that stars have a mostly fixed place on the Celestial Sphere, such that what you can see and when you see it is determined by the rotation of the earth, and the position of the sun in the sky.
Planets are somehow special.