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Tsync Tsync
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8 years ago
What use are 21 cm radio waves to galactic astronomers?
A) They cut through the dusty cocoons to let us watch star birth.
B) They pick up the cool, dark matter much better than can optical telescopes.
C) We can reflect them off the core of the Galaxy.
D) They bounce off stars like our Sun to let us precisely measure their distances.
E) Their Doppler shifts let us map the motions and locations of gas in the spiral arms.
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Astronomy Today

Astronomy Today


Edition: 8th
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Minoring in physics
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RatatouilleRatatouille
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8 years ago
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Tsync Author
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8 years ago
Exactly what I needed Smiling Face with Open Mouth
Minoring in physics
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8 years ago
Happy to help Slight Smile
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