The force that keeps planets on their orbit...

• orbit
• stars
• planets
• gravity

Atmosphere is :

• only consisting of argon and oxygen
• gases on the floor of the Earth
• all the gases around a planet
• all the gases near the solar beams

The path a planet takes as it revolves around the sun

• phase
• orbit
• galaxy directed
• gravitational force

Why don’t astronauts’ muscles and bones stay strong while in space?

• They do not have enough food to eat.
• There is no weight to put pressure on their muscles and bones.
• They are not able to exercise in space.
• They do not have muscles in space.

Why are rockets needed to get to space?

• They carry the astronauts in the nozzle.
• They have the ability to overcome Earth’s gravity.
• They use less fuel than other space craft.
• They are the safest mode of travel.

The only planet that can support life is _____________________________.

• Mercury
• Neptune
• Pluto
• Earth

Astronauts use special soap that _____.

• does not require a washcloth
• does not require water to rinse
• has strong chemicals
• does not have an odor

How would astronauts traveling to Mars have enough water for such a long trip?

• They would get it from the sink.
• They would store enough on board for the entire trip
• They would need to ration and recycle their water.
• They would not need much water.

Which is not a reason we need special suits for space exploration?

• regulate temperature
• provide oxygen (O2)
• protect from radiation
• keep the astronaut cool

What is the habitable zone?

• A zone with the correct distance away from a star
• A zone in space where water turns into vapor
• A zone where life can not be sustained
• A zone in space where water is frozen