What Observations Convince Us That the Energy Source of a Quasar

question 80

Multiple Choice

What observations convince us that the energy source of a quasar is physically very small?

• A) rapid fluctuations in brightness since variations over 1 day mean that the source must be less than 1 light-day across
• B) instant disappearance of the quasar when occulted by the Moon's edge as the Moon moves in front of a quasar, indicating a very small source size
• C) sharpness of the emission lines in their optical spectra since motions within a large source would smear out the line shapes
• D) extremely small size of the image of a quasar, even from Hubble Space Telescope images and radio interferometry measurements

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Definitions:

Density

In social contexts, it refers to the degree of closeness or connectedness in social networks; in physical contexts, it describes the concentration of matter in a given space.

Limited Space

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Steinzor Effect

A phenomenon observed in communication patterns within groups, suggesting that individuals tend to respond more frequently to the last person who has spoken, influencing the flow of discussion.

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The manner in which an individual positions themselves while seated, which can affect their posture and health.