Astronomy C Test - Science Olympiad Hawk and Hornet 2026 Invitational

These flashcards cover key concepts from the Astronomy C test from the Science Olympiad Hawk and Hornet 2026 Invitational lecture notes, aiding in exam preparation.

What are standard candles?

Objects with a known absolute magnitude.

What does Kepler’s Third Law relate to?

It relates Gravitational Force and Centrifugal Force.

What is the relation that Cepheids and RR Lyrae variables follow?

Period-Luminosity Relationship.

What element causes pulsation in Cepheid and RR Lyrae stars?

Hydrogen.

How does increased ionization of the mentioned element affect opacity and radiation escape?

More ionized means more opaque, allowing less radiation to escape.

What classification does a stellar classification of V denote?

Main Sequence.

When does the blue loop in stellar evolution occur?

After the Horizontal Branch stage.

What are Population I stars?

Metal-Rich, Younger Stars.

What precedes the horizontal branch on an HR diagram?

Helium Flash.

Where do white dwarfs appear on the Hertzsprung-Russell Diagram?

Lower Left.

What stage of evolution results in Carbon Stars?

Asymptotic Giant Branch.

What happens to the orbital radius if a planet's orbital period is doubled?

It increases by a factor of 4.

From which law is Kepler’s 2nd Law derived?

Newton’s Law of Gravitation.

Why are standard candles important in astronomy?

They help determine distances to objects in space.

What are the end states of stars after nuclear fusion ordered from lowest to highest mass?

White Dwarf, Neutron Star, Black Hole.

What is a classical nova?

A cataclysmic variable star system where a white dwarf accretes hydrogen from a companion star and undergoes runaway nuclear fusion.

Why does a star's radius decrease during a Helium Flash?

The outer layers contract as helium fusion begins in the core.

How was the Schwarzschild Radius derived?

It was derived from the solutions to Einstein's equations of general relativity.

Why are protostars generally brighter than main-sequence stars?

They are still contracting and converting gravitational energy to thermal energy.

Why can no star fuse iron?

Because iron has the lowest binding energy per nucleon and fusion would not produce energy.