Take the quiz:

1) Pluto was discovered by ______________.

Mike Brown

Venetia Burney

Glenn Seaborg

Clyde Tombaugh

Clear selection

2) True or false: according to the IAU definition, a planet must be visible to the naked eye.

True

False

Clear selection

3) True or false: The Kuiper belt consists mainly of small rocky bodies.

True

False

Clear selection

4) The _____________ were/was the first to define a planet.

International Astronomical Union

Romans

Lowell Observatory

Greeks

Clear selection

5) The orbit of a planet is in the shape of a(n) ___________.