The Method Used by Harlow Shapley in 1917 to Estimate

question 87

Multiple Choice

The method used by Harlow Shapley in 1917 to estimate the Sun's location in our Galaxy was the measurement of the

• A) locations of globular clusters around the Galaxy.
• B) density of stars in different directions along the Milky Way.
• C) distances to open star clusters and H II regions in the disk of the Galaxy.
• D) structure of the Andromeda Galaxy,and comparing it with the structure of our Galaxy.

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Definitions:

Pilot Control Device

A mechanism or component used to regulate the operation of machinery or systems through the control of smaller power inputs.

Loss of Power

A situation where electrical power is interrupted or unavailable to a device or area.

Two-wire Motor

A motor designed to be operated with two electrical connections, typically for power and ground.

Motor Control Circuits

Electrical circuits specifically designed to control the operation and performance of electric motors.