The Identification of "Spiral Nebulae" as Large Groupings of Stars

question 52

Multiple Choice

The identification of "spiral nebulae" as large groupings of stars outside of our own galaxy was proven by ____.

• A) photographic plates made by Edwin Hubble showing stars and Cepheid variables
• B) the results of the Shapley-Curtis debate
• C) Immanual Kant's "island universe" theory
• D) William Parsons' observation and description of their spiral structure
• E) Harlow Shapley's observations of their radio spectrum

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Definitions:

Placebo Effect

A beneficial effect, produced by a placebo drug or treatment, that cannot be attributed to the properties of the placebo itself, and must therefore be due to the patient's belief in that treatment.

Gender Bias

A predisposition or preconceived notion that leads to unfair treatment or assessment of people based on their gender.

Male Behavior

Actions, attitudes, or responses that are traditionally or typically associated with men or male roles in a society.

Female Behavior

Refers to the patterns of action or conduct that are typically observed or expected from females, influenced by genetic, cultural, and social factors.