13.1 Astronomical Measurements and Concepts

What is the electromagnetic spectrum (EM)?

• A range of sound waves

• A continuous range of radiation arranged by wavelength

• A collection of visible light colors

• A type of telescope

What is a spectroscope used for?

• To collect visible light

• To spread light into different wavelengths

• To magnify distant objects

• To measure sound waves

How far is one astronomical unit in kilometers?

• 100 million km

• 150 million km

• 200 million km

• 250 million km

What is the distance from the Sun to Venus in astronomical units?

• 0.4 AU

• 0.7 AU

• 1 AU

• 1.5 AU

What is the distance from the Sun to Mars in astronomical units?

• 0.4 AU

• 0.7 AU

• 1 AU

• 1.5 AU

Why is it convenient to use astronomical units in the solar system?

• It is easier to compare distances

• It is a smaller unit

• It is used for measuring time

• It is a universal unit for all measurements

What is the purpose of using two points in Earth's orbit for parallax?

• To measure the speed of planets

• To create angles for measuring distances

• To determine the color of stars

• To calculate the mass of planets

What is a light-year used to measure?

• Time

• Distance

• Speed

• Weight

How do astronomers measure the brightness of stars?

• By their color

• By their size

• By how bright they look from Earth and how bright they really are

• By their temperature

What happens when you look at a star in terms of time?

• You see it as it is now

• You see it as it was when the light left it

• You see it in the future

• You see it in slow motion