Long period comets originate from the O..... C....

Comets are largely made of i...

As comets approach the Sun, ice and other gasses evaporate forming the comet's t___

The earliest known accurate star map of the Southern Hemisphere was created by....

• JOHANNES KEPLER

• GALILEO GALILEI

• ISAAC NEWTON

• EDMOND HALLEY

The most massive object in this solar system is the ....

• Venus

• Jupiter

• Sun

• Neptune

The c___ is the smallest unit of life (excepting viruses, if you consider them alive) -- sometimes called the building block of life.

Using an early microscope, __________ discovered and named the cell.

• ROBERT HOOKE

• CHARLES MESSIER

• HENRIETTA SWANN LEAVITT

• EDWIN HUBBLE

Johannes Kepler demonstrated that, instead of orbiting in perfect circles, planetary orbits are ....

• cone

• elliptical

• sphere

• circle

The closer a planet is to the Sun, the __________ the planet moves.

• faster

• slower

Who invented the reflecting telescope?

• Galileo Galilei

• Edmund Halley

• Johannes Kepler

• Isaac Newton