We Detect Neutral Gas in the Interstellar Medium by Looking

question 55

Multiple Choice

We detect neutral gas in the interstellar medium by looking for radiation at 21 cm that arises when

• A) an electron moves from the n = 1 to n = 2 state in a hydrogen atom.
• B) an electron is ionized from a hydrogen atom.
• C) carbon monoxide (CO) gas is excited by stellar radiation.
• D) an electron's magnetic poles flip and align with the magnetic poles of a proton in a hydrogen atom.
• E) an electron combines with a proton to make a hydrogen atom.

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Definitions:

Siphons Sugars

A non-standard term possibly referring to the process of moving sugars within plants or between organisms, though not a widely recognized key term in this exact wording.

Infects Trees

Describes a pathogen or parasite that attacks or causes disease in trees.

Glomeromycetes

Fungi that partner with plant roots; their hyphae grow inside cell walls of root cells.

Soil Fungi

Fungi that live in the soil, playing critical roles in nutrient cycling, organic matter decomposition, and as symbionts or pathogens of plants.