The Formation
of the Solar System
of the Solar System
An oval shape that is centered on two points instead of a single point, like a circle
What is an ellipse?
The four inner planets are called this because they are similar in density to Earth and have solid, rocky surfaces.
What are terrestrial planets
A planet-like object in space that has not cleared its orbit of smaller debris
What is a dwarf planet?
A streak of light produced when a meteoroid passes through Earth's atmosphere and is heated by friction and compression
What is a meteor?
These objects, ranging in size from 1km to hundreds of km in diameter, were formed by colliding particles in the early solar system.
What are planetesimals?
Jupiter, Saturn, Uranus, and Neptune are also known as this kind of planet
An asteroid fragment, or any other interplanetary material
What is a meteoroid?
This gas produces the blue color of Uranus and Neptune.
What is methane?
The apparent backward movement of a planet
What is retrograde motion?
A planet-wide system of cliffs on Mercury
What are scarps?
What is the Kuiper Belt
Part of a meteor that does not burn up completely and hits the ground
What is a meteorite?
A unit of measurement based on Earth's average distance from the Sun
That is an astronomical unit (AU)?
This form of hydrogen has properties of both a liquid and a metal and can exist only under extreme pressure.
What is liquid metallic hydrogen?
These small icy bodies have highly eccentric orbits around the Sun.
What are comets?
Comet tails always point in this direction
What is away from the Sun?
This ratio of the distance between the foci to the length of its major axis defines the shape of a planet's elliptical orbit.
What is eccentricity?
Low, warm, dark-colored clouds that sink AND high, cool, light-colored clouds that rise
What are belts and zones?
These bright streaks of light occur when Earth passes the trail of a comet and particles left in the trail burn up in Earth's upper atmosphere.
What is a meteor shower?
The outermost region of the solar system that surrounds the sun and where most comets originate
What is the Oort cloud?