Front

In 1 year, light travels ___________ trillion kilometers.

Back

9.5

Front

A light-year is the distance that light travels in ____year/s.

Back

1

Front

Why does only a small part of a star’s light reach Earth?

Back

The light spreads out as it moves through space.

Front

How does the temperature of these stars affect their apparent brightness?

Back

The greater the temperature, the greater the apparent brightness.

Front

What size star is the sun?

Back

medium

Front

What is a light-year?

Back

A unit of distance that light travels in one year.

Front

What is the main reason the Sun appears brighter than other stars?

Back

The Sun is much closer to Earth than other stars.

Front

What color are the hottest stars?

Back

Blue

Front

What is the relationship between a star's temperature and its color?

Back

Hotter stars are blue, while cooler stars are red.

Front

What is the main source of the Sun's energy?

Back

Nuclear fusion in its core.