8th grade 5th 6 weeks Universe

Where in the Milky Way is the Earth found?

• In the middle of the galaxy

• About 1 light-year from the middle of the galaxy

• Varies depending on where it is in the orbit around the Sun

• In the spiral arm of the galaxy

Why does Earth get more energy from the sun than from all the other stars in the universe combined?

• The sun is much larger than the other stars

• The sun is much hotter than the other stars.

• The sun is much closer than the other stars.

• The sun is much more dense than the other stars.

Scientists recently discovered a giant runaway star. It is 90 times larger than the sun and is very hot and blue-white in color. Why does the sun appear to be brighter than this runaway star when viewed from Earth?

• The sun is closer to Earth than the runaway star

• The sun is made of different elements than the runaway star.

• The sun is older than the runaway star.

• The sun is a different color than the runaway star.

Most of the space in the universe is empty. Part of the reason for the emptiness of space is that the matter in the universe is gravitationally attracted to other pieces of matter. Most matter in the universe gets pulled into one of the many massive systems held together by the gravitational pull of black holes. These massive systems can be millions of light years wide and contain millions of stars and planets. What do scientists call these massive systems?

• Solar systems

• Nebulae

• Galaxies

• Planetary systems

Electromagnetic waves travel through many materials very quickly. This property has been utilized in many ways. Which of these do not use electromagnetic waves?

• x-ray machines

• Electric fans

• Radio

• Cell phones

The universe has many different components. Which list places four components of the universe in the most likely order from smallest to largest?

• Planets, stars, galaxies, nebulae

• Nebulae, stars, planets, galaxies

• Galaxies, stars, planets, nebulae

• Planets, stars, nebulae, galaxies

Based on the information given, how do radio waves compared to visible light waves on the electromagnetic spectrum?

• Visible light waves have longer wavelengths and more energy than radio waves.

• Visible light waves have shorter wavelengths and more energy than radio waves.

• Visible light waves have longer wavelengths and less energy than radio waves.

• Visible light waves have shorter wavelengths and less energy than radio waves.

Four students are asked to describe a nebula and a star. Their responses are in the table. Which student described these bodies correctly?

• Student 1

• Student 2

• Student 3

• Student 4

The Hertzsprung-Russell diagram shows how the sun is classified among the stars. A star that is several thousand times brighter than the sun with a temperature lower than 4,000 K would be classified as

• a main-sequence star in spectral class B

• a supergiant in spectral class K

• a main-sequence star in spectral class K or M

• a white dwarf in spectral class B

Two stars are identified on the Hertzsprung-Russell Diagram. Based on this diagram, how do the characteristics of Star 1 and Star 2 compare?

• Star 1 is cooler and less bright than Star 2.

• Star 1 is hotter and brighter than Star 2.

• Star 1 is cooler and brighter than Star 2.

• Star 1 is hotter and less bright than Star 2.