In 1974 a Radio Signal Was Sent from the Arecibo

question 55

Multiple Choice

In 1974 a radio signal was sent from the Arecibo radio telescope toward the globular cluster M13, which is about 6.8 kpc distant. How long will it take this signal to reach M13?

• A) 6800 years
• B) 13,600 years
• C) 22,200 years
• D) 44,400 years

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Definitions:

Sensory Stimulus

An external or internal event or factor that initiates a sensory response in an organism, leading to a potential change in behavior or physiological state.

Perception

The meaning a brain derives from a sensation.

Sensation

Detection of a stimulus.

Hair Cells

Sensory cells found in the inner ear that are responsible for converting sound vibrations into electrical signals that the brain can understand.