What Causes the Characteristic Blue Color of a Reflection Nebula

question 58

Multiple Choice

What causes the characteristic blue color of a reflection nebula?

• A) electrons dropping between energy levels n = 3 and n = 2 in hydrogen atoms
• B) electrons dropping between energy levels n = 2 and n = 1 in hydrogen atoms
• C) thermal blackbody radiation emitted by the hot gas
• D) scattering of starlight from dust grains in the nebula

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Definitions:

Allowance Factor

A factor used in planning and estimation to account for potential deviations from standard conditions or expected performance.

Normal Time

The amount of time typically required to complete a process or task under normal conditions, often used in planning and scheduling.

Standard Time

The established timeframe set to complete a specific task or process under normal conditions.

Labour Standards

The established amount of time required to perform a task, based on measurements of work performance, used for planning and payroll purposes.