Radio Waves of 21-Cm Wavelength Originate from Which Component of the Interstellar

question 318

Multiple Choice

Radio waves of 21-cm wavelength originate from which component of the interstellar medium?

• A) cool, neutral atomic hydrogen
• B) cold molecular hydrogen, H₂
• C) cool carbon monoxide, CO
• D) hot, ionized atomic hydrogen

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Definitions:

Insects

Most diverse arthropod group; have six legs, two antennae, and, in most subgroups, wings.

Bacteria

Single-celled, prokaryotic microorganisms that come in various shapes and can inhabit a wide range of environments, including soil, water, and living in or on other organisms.

Fungi

A kingdom of complex organisms that include molds, yeast, mushrooms, and more, distinct from plants and animals.

Niche Overlap

Refers to the condition where two or more species occupy overlapping niches, sharing resources in the same environment, which can lead to competition.