What Use Are 21 Cm Radio Waves to Galactic Astronomers

question 33

Multiple Choice

What use are 21 cm radio waves to Galactic astronomers?

• A) They cut through the dusty cocoons to let us watch star birth.
• B) We can reflect them off the core of the Galaxy.
• C) Their Doppler shifts let us map the motions and locations of gas in the spiral arms.
• D) They bounce off stars like our Sun to let us precisely measure their distances.
• E) They pick up the cool, dark matter much better than can optical telescopes.

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Definitions:

Central Executive

A component of working memory model that is responsible for directing attention and orchestrating cognitive processes when performing tasks.

Long-term Potentiation

A long-lasting enhancement in signal transmission between two neurons that results from stimulating them simultaneously, associated with learning and memory.

Baseball Game

is a competitive sport involving two teams, each trying to score runs by hitting a ball and running around a series of bases, played on a field.

Selective Attention

The mental process of focusing on one specific aspect or stimulus in the environment, while ignoring others.