Why Is 21-Cm Radiation the Best Way to Map the Spiral

question 58

Multiple Choice

Why is 21-cm radiation the best way to map the spiral arms in the Milky Way?

• A) The molecular hydrogen gas that produces this emission is concentrated in the spiral arms.
• B) These photons,which are produced by neutral hydrogen,penetrate the dense clouds of gas and dust in the disk.
• C) This synchrotron emission is produced by supernovae,which are concentrated in the spiral arms.
• D) Radio telescopes are easier to operate than optical telescopes and observations can be made even during the daytime.

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Definitions:

Spatial Reasoning

The capacity to understand, reason, and remember the spatial relations among objects or space.

Intellectual Functioning

Refers to cognitive capabilities, including reasoning, problem-solving, planning, and abstract thinking.

Severe Discrepancy

A significant gap often referred to in education and psychology, which indicates a substantial difference between expected performance, based on age or grade, and actual performance, often used in diagnosing learning disabilities.

Intellectual Functioning

The general capacity of an individual to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience.