How Do We Know That AGNs Have Sizes on the Order

question 26

Multiple Choice

How do we know that AGNs have sizes on the order of our Solar System?

• A) Quasars and Seyfert galaxies are stellar-like sources.
• B) Their brightness varies by factors of a few.
• C) The emission lines in their spectra show gas rotating at speeds of thousands of km/s.
• D) Their brightness varies on timescales ranging from hours to a day.
• E) We can measure their angular size, which gives us the physical size when we know the distance.

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Definitions:

Shared Goals

A concept referring to objectives or aims that are pursued jointly by members of a group or team.

Collaboration

The action of working with someone to produce or create something, involving mutual engagement and cooperation.

Holacracy

An organizational structure where power and decision-making are distributed throughout self-organized teams rather than being centralized in a traditional management hierarchy.

Strategize

The action of planning or devising a course of action or policy to achieve a major or overall aim.