The Distinct Blue Color of the Nebulosity Around Stars in Young

question 35

Multiple Choice

The distinct blue color of the nebulosity around stars in young clusters,such as the Pleiades,is caused by

• A) light emitted by very hot gas which has been heated by collisions in the interstellar gas.
• B) preferential scattering of blue starlight by small dust grains in the interstellar material.
• C) atoms of gas emitting light by fluorescence,having been excited by ultraviolet radiation from hot stars.
• D) halos caused by refraction of starlight in ice crystals in the nebula,similar to halos seen occasionally in Earth's atmosphere.

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Definitions:

Reaction Formation

A psychological defense mechanism in which an individual unconsciously replaces their true feelings perceived as unacceptable with their opposite.

Projection

A psychological defense mechanism where individuals attribute their own unacceptable thoughts, feelings, or motives to someone else.

Positive Adjustment

The process of adapting positively to circumstances, challenges, and changes, contributing to mental health and well-being.

Withdrawal

The process or symptoms of ceasing to use an addictive substance, which can include physical and mental health effects.