Earth and Space Sciences: Redshift and Blueshift

Earth and Space Sciences: Redshift and Blueshift

• Earth and space sciences include redshift and blueshift theories.

• Understanding how these theories work is essential.

Frequency Shifts Explained with a Fire Truck Example

• Scenario: An observer is stationary, and a fire truck emits sound frequencies.

  • The fire truck's siren emits a frequency of $800$ Hz.

Blueshift

• When the fire truck is moving towards the observer, the sound appears high-pitched.

• This phenomenon is known as blueshift, where the observed frequency increases when an object moves towards the observer.

Original Frequency

• When the fire truck is at the same location as the observer, the perceived pitch of the siren sounds normal.

• The observed frequency matches the actual frequency emitted by the siren ($800$ Hz).

Redshift

• As the fire truck moves away from the observer, the sound appears lower-pitched.

• This is known as redshift, where the observed frequency decreases as the object moves away.