Astronomers Can Now Report That Active Star Formation Was Going

question 32

Multiple Choice

Astronomers can now report that active star formation was going on at a time when the universe was only 20% as old as it is today. When astronomers make such a statement, how can they know what was happening inside galaxies way back then?

• A) they look at the open clusters in the Milky Way Galaxy
• B) they look at radio waves coming from nearby active galaxies
• C) they look at a graph that shows the way galaxy redshifts change with time
• D) they look at the elements in comets, which formed when our solar system was first forming
• E) they examine the spectra of galaxies (or the overall colors of galaxies) with the highest redshifts they can find

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Definitions:

Aversive Conditioning

A behavior conditioning technique in which unpleasant stimuli are associated with undesirable behaviors to discourage those behaviors.

Negative Response

An adverse or unwelcoming reaction to a stimulus, situation, or input.

Aversive Conditioning

A form of behavior therapy that involves reducing undesirable habits by teaching the subject to associate an unpleasant or aversive stimulus with the habit.

Electric Shock

A sudden discharge of electricity through a part of the body, potentially causing injury or neurological effects.