Space Physics - The Solar System

What shape are the orbits of comets?

• Elliptical

• Rectangular

• Irregular

Answer explanation

All bodies in space move in elliptical orbits.

Which body was the first stage in the formation of the Sun?

• A nebula

• A protostar

• A nova

Answer explanation

The Sun formed from a nebula (dust and gas) that collapsed because of its gravity.

What is a comet?

• An object that orbits the Earth, made from rocky material, dust and ice

• An object that orbits the Sun, made from rocky material and metals

• An object that orbits the Sun, made from rocky material, dust and ice

Answer explanation

A comet is made from rocky material, dust and ice, and orbits the Sun.

What sort of reaction mainly happens in the Sun?

• Nuclear fission

• Nuclear fusion

• Chemical

Answer explanation

Nuclear fusion happens in the Sun when hydrogen nuclei combine to form helium nuclei. The Sun is too hot for chemical reactions to occur.

Which of the following is a natural satellite?

• The Moon

• The International Space Station

• The Hubble Space Telescope

Answer explanation

The Moon is a natural satellite of the Earth. It is not man-made, and it orbits a planet.