Introduction to the Solar System

How old is our Solar System?

• 4.6 billion years old

• 6.2 billion years old

• 10.0 billion years old

• 13.7 billion years old

Which set of planets are all classified as terrestrial?

• Earth, Saturn, Mars, Jupiter

• Venus, Neptune, Jupiter, Mercury

• Mercury, Venus, Earth, Mars

• Jupiter, Saturn, Uranus, Neptune

According to the Solar Nebular Theory, which event happened first that formed our Sun?

• gravitational collapse of a nebula

• a shockwave from a supernova

• nucleosynthesis

• clumping together of rocks in space

Which planet/s in our Solar System have rings?

• Saturn

• Jupiter, Saturn

• Mars, Jupiter, Saturn

• Jupiter, Saturn, Uranus, Neptune

Which planet in our Solar System has the coldest surface temperature?

• Neptune

• Uranus

• Mars

• Saturn

Answer explanation

The coldest planet is not Neptune, but Uranus – even though Uranus is a billion miles closer to the Sun than Neptune. Uranus holds the record for the coldest temperature ever measured in the Solar System: a very chilly -224℃. The temperature on Neptune is still very cold, of course – usually around -214℃ – but Uranus beats that.

The reason why Uranus is so cold is nothing to do with its distance from the Sun. Billions of years ago, something big crashed into Uranus with so much force that it tipped the planet over onto its side and also let some of the heat that was trapped inside Uranus escape.

The heat inside planets is left over from when they were formed. Neptune wasn’t hit by a huge asteroid like Uranus was, so it has been able to hold on to more of its heat.

Which is true about the planet Earth and its distance from the Sun?

• It is the second planet from the Sun.

• It is the third planet from the Sun.

• It is the fourth planet from the Sun.

• It is the fifth planet from the Sun.

Which planet is the closest neighbor to Earth in terms of distance?

• Venus

• Mercury

• Jupiter

• Mars

How many total planets are there in our Solar System? (NOT counting dwarf planets)

• seven

• eight

• nine

• ten

Under what category do stars and galaxies fall under?

• dark matter

• light matter

• baryonic matter

• dark energy

Which is believed by scientists to be responsible for the continuing expansion of our universe?

• dark matter

• light matter

• baryonic matter

• dark energy