Science quiz.

The absolute brightness of a star depends on its ______.

• Distance and temperature.

• Color and temperature.

• Distance and color.

• Size and temperature.

A Hertzsprung-Russell diagram like the one below classifies stars according to certain properties.

Which of the following changes would correspond to a decrease in a star's absolute brightness?

• A decrease in a star’s distance.

• An increase in a star’s temperature.

• A decrease in a star’s temperature.

• An increase in a star’s size.

About 90 percent of the stars in space are ______ stars.

• Main sequence.

• Giant.

• White dwarfs.

• Nebula.

Most stars in the Universe are like the Sun. The table lists the 10 most common elements in our Sun

and their abundance. How does the chemical makeup of MOST stars in the Universe compared to

that of our Sun?

• Most stars are about 10 percent Nitrogen.

• Most stars are about 98 percent Hydrogen and Helium.

• Most stars have more Helium than Hydrogen.

• Most starts are composed of primarily Helium and Carbon.

The colors of main sequence stats range from blue to white, yellow like the sun, and from orange to red, in general, red stars are __________.

• Cooler than the sun.

• Closer than the sun.

• Smaller than the sun.

• Older than the sun.

What is the order of these objects from the smallest to the largest size?

• 4-3-2-1

• 2-3-4-1

• 2-1-4-3

• 1-2-3-4

Stars seem to be made up of similar chemical elements. Which characteristics are used to

differentiate among stars?

• Size, age, and speed of revolution.

• Age, temperature, and size.

• Weight, age, and temperature.

• Age, speed of rotation and color.

Uri looks through a telescope for two stars. He knows that both stars have the same absolute brightness and that the second star is twice as far from Earth as the first star. How bright will the second star appear compared to the first star?

• It will appear as bright as the first star.

• It will appear dimmer than the first star.

• It will appear brighter than the first star.

• It will appear redder than the first star.

Stars can be many different colors. Which star in the chart has the highest surface temperature?

• Star C

• Star A

• Star B

• Star D

A science fiction movie shows a spaceship traveling past Pluto, Saturn, the Moon, and the Andromeda galaxy. Which of these celestial objects is the farthest from the Sun?

• The Andromeda galaxy

• Pluto

• the moon

• Saturn