U2L2 Stars

Which of the following units is used to express the size of stars?

• kilometer

• light-year

• solar radius

• astronomical unit

The table compiles information about the distance of various stars from Earth, their apparent magnitude, and their absolute magnitude. Based on evidence in the table, which of the stars would look the brightest when observed from Earth?

• Sirius

• Rigel

• Arcturus

• Aldebaran

Which statement best describes stars?

• large planets that are composed mostly of gases

• celestial bodies made up of gas that give off light

• faint dots of light that can be seen from Earth's surface

• objects that form in the outer parts of the solar system

Two stars have the same apparent magnitude as seen from Earth’s surface. Star A is 33 ly away. Star B is 346 ly away. Which of the following claims is supported by the evidence?

• Star B is larger than Star A

• Star B is more luminous than Star A

• The stars have the same absolute magnitude

• Star A has a smaller absolute magnitude

Which of the following statements best describes a binary star system?

• A star appears blue in the night sky

• A star is orbited by a gas giant planet

• Two pairs of stars orbit each other

• Two stars orbit each other

the brightness of a star as seen or appears from Earth

• apparent magnitude

• luminosity

• absolute magnitude

• light year

How bright a star would be if at a standard distance

• apparent magnitude

• absolute magnitude

• light year

• binary star

the true brightness of an object

• luminosity

• apparent magnitude

• solar radii

• parallax

When talking about apparent magnitude, what kind of stars have positive (larger) numbers?

• Faint stars

• Bright stars

A negative number on the apparent magnitude scale refers to a ...?

• dimmer star

• brighter star