Only Eight Planets?

                                   Only Eight Planets?

Pluto was discovered in 1930 by Clyde W. Tombaugh. It was thought to be the ninth planet in our solar system. However, the term planet had never been defined. Many people wondered if Pluto should be called a planet. In 2006, scientists finally agreed on what makes a planet a planet. Planets must now pass three tests.

Pluto did not pass all of the tests. Pluto is now called a dwarf planet. Many other dwarf planets have been discovered in our solar system.

Solve It

Pluto is very small compared to the planets. it is even smaller than our moon.
Round each of these measurements to the nearest 100 km to make it easier to compare.

1.    Distance through the center of Pluto: 2,274 km                       __________________________

2.    Distance through the center of Earth's moon: 3,476 km           __________________________

3.   Distance through the center of Mercury: 4,487 km                   __________________________

4.   Distance through the center of Mars: 6,794 km                        __________________________

Taken from: MonsterMathBlogger