Stars

What information can be revealed about a star by analyzing its spectrum?

• Its distance from Earth

• Its age and future lifespan

• Its composition and temperature

• Its rotational speed

Select all correct answers. What colors can stars appear?

• White

• Red

• Blue

• Green

Hotter stars appear to be on the _______ end of the spectrum

• blue
• yellow
• red
• green

Which letter represents the hottest stars in the current star classification system?

• A

• B

• O

• M

Why do we not observe green stars, even though some stars might emit the most light in the green spectrum?

• Green light is absorbed by interstellar dust.

• Our eyes mix the emitted colors, making them appear white.

• Green stars are too far away to be seen.

• Stars only emit light in red, blue, and yellow wavelengths.

What does luminosity measure?

• How bright a star appears from Earth.

• The actual amount of energy a star gives off.

• A star's distance from Earth.

• A star's temperature.

Which two physical characteristics primarily determine a star's luminosity?

• Color and distance.

• Age and composition.

• Size and temperature.

• Mass and rotation speed.

What two stellar properties are plotted on a Hertzsprung-Russell (HR) diagram?

• Mass and age.

• Distance and apparent brightness.

• Luminosity and temperature.

• Color and size.

What is the primary process by which stars on the main sequence generate energy?

• Fusing helium into carbon.

• Gravitational collapse.

• Fusing hydrogen into helium.

• Burning fossil fuels.

White dwarf stars are the result of

• the byproducts of stellar fusion in red giants
• the cores of stars that have collapsed into black holes
• the remnants of massive stars after a supernova
• the remnants of low to medium mass stars after they have exhausted their fuel