1. Evidence for Revolution
Earth Science
Mr. Cloud

2. 1. Stellar Parallax
The apparent shifting of a distant star in comparison to its background.
If observing the cosmic background, a distant star will appear to ‘shift’ in our view due to our changing perspective.

3. The angle of the sun changes in a cyclic pattern throughout the year.
The angle of incidence is higher in summer than in winter due to Earth’s changing position in relation to the sun.
If the Earth were stationary, we would never experience the change of season on Earth.
2. The Seasons

4. 3. Constellations
Constellation: is a grouping of stars that help us locate positions in the night sky.
Throughout the year we observe the night sky changing in a cyclic manner.
As the Earth revolves, we observe different areas of the observable cosmos.
Some constellations shift with the seasons.

5. 4. Apparent Diameter of the Sun
As the Earth revolves closer the sun (towards Perihelion), the apparent diameter of the sun increases.
As the Earth revolves away (towards aphelion), the apparent diameter decreases.

6. 5. Doppler Shift
As the Earth approaches a distant star, light from that star shifts to the blue end of the visible spectrum: Blue Shift
As the Earth moves away from the star, light from that star shifts to the red end of the visible spectrum: Red Shift