How Do We Know That at Least One Generation of Stars

question 18

Multiple Choice

How do we know that at least one generation of stars formed and died before the Milky Way's globular clusters formed?

• A) The stars of the oldest globular cluster have some heavy elements.
• B) They are so old that nuclear fusion in globular cluster stars has altered their chemical abundances.
• C) Globular clusters have a much higher hydrogen content than expected.
• D) The RR Lyrae stars found in globular clusters must be second-generation stars.
• E) All globular clusters reside in the disk of the Milky Way.

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Definitions:

Area

The extent of a two-dimensional surface within a boundary.

Multiply

The process of combining two numbers or quantities to get their product.

Simplify

Reducing a mathematical expression or equation to its most basic form without changing its value.

Special Product Pattern

Formulas that simplify the multiplication of algebraic expressions.