Astronomy Planets

What are planets?

spinning bodies of rock or gas that orbit around a star

What keeps the planets moving around the sun?

the sun's strong gravitational pull

Which planets are the rocky planets?

Mercury, Venus, Earth, Mars

Which planets are the gas planets?

Jupiter, Saturn, Uranus, Neptune

How did Mercury, Venus, Mars, Jupiter and Saturn get their name?

The ancient Greeks and Romans named them after their gods.

What are the 2 ways that satellites move?

-they orbit around planets -they spin on their own axis

Describe the atmosphere of Mercury.

a thin sodium cloud

Describe the atmosphere of Venus.

98% carbon dioxide (traps the heat)

Describe the atmosphere of Earth.

oxygen and nitrogen (protects from the sun's rays)

Describe the atmosphere of Mars.

thin, carbon-dioxide

What are asteroids?

chunks of rock that orbit the sun

Where is the asteroid belt located?

between the orbits of Mars and Jupiter

What gases are found on the gas planets?

hydrogen, helium, methane, ammonia, water vapor

What is a comet?

an object made of gas, ice, and dust that orbits around the sun

What is a meteorite?

a rock from space that hits the Earth

What is a meteor?

also called a shooting star, a rock in space that may hit Earth's atmosphere

What is a meteoroid?

a small piece of an asteroid or comet orbiting the sun

Pluto is now considered to be a...

dwarf planet

Name some features of the gas planets.

ex: no solid surface, rings, complex storms, low density, far from the sun

Name some features of the rocky planets.

ex: solid surface, heavy metal core, significant atmosphere, volcanoes