Chapter 10 The solar system

How is the Universe described in the text?

• A collection of galaxies

• A collection of planets

• A collection of comets

• A collection of stars

What is the Milky Way?

• A planet

• A galaxy

• A star system

• A cloud of dust

What is the estimated number of galaxies in the Universe?

• 100 billion

• 50 billion

• 200 billion

• 10 billion

Stars are ___________ while planets are ___________.

What is the speed at which light travels?

• 300,000 km per minute

• 300,000 m per second

• 300,000 km per second

• 300,000 m per minute

The Pole Star does not appear to move because it is in line with Earth’s ____________.

___________ takes place when one planet or moon blocks off light from another.

Events based on the lunar calendar, like Ramadan, move through the solar calendar approximately 11 days earlier every ___

The lunar year is about ___ days shorter than the solar year.

The Gregorian calendar is based on the Earth's orbit around the Sun, with ___ months in a year.