Planets
Mars
Rocky remnants from the early solar system, found primarily in the belt between Mars and Jupiter.
asteroids
the force of attraction between any two objects
gravity
As the mass of an object increases, the force of gravity acting on the object
increases
a geometric shape that looks like a flattened circle.
ellipse
Name the four Jovian planets in order.
Jupiter, Saturn, Uranus, Neptune
Larger meteors that survive atmospheric entry and reach the surface are known as
meteorites
proposed by Nicolaus Copernicus in the 16th century, suggested that the Sun was at the center of the solar system, with planets, including Earth, orbiting it.
the heliocentric model
As the distance between two objects increases, the force of gravity
decreases
defined as the set of all points where the sum of the distances to two fixed points (foci) is constant
ellipse
What is the hottest planet?
Venus
also known as “dirty snowballs” are icy bodies that originate in the outer regions of the solar system.
Comets
proposed that Earth was the center of the universe, and all celestial objects orbited around it.
geocentric model
An imaginary line joining a planet to the sun will sweep over equal areas in equal periods of time. (which law)
Law #2: Law of Equal Areas
when a planet is closest to the sun there is greater gravitational attraction, so the planet moves faster.
perihelion
What are the Jovian planets mostly composed of?
hydrogen and helium
celestial bodies that share characteristics with both planets and asteroids.
dwarf planets
a region beyond Neptune containing many icy objects.
The Kuiper Belt
The orbits of the planets around the sun are ellipses, with the sun located at one focus. (which law)
Law #1: Law of Ellipses
when a planet is farthest from the Sun there is less gravitational attraction, so the planet moves slower.
aphelion
What planet has evidence of past water flow?
Mars
Neptune's moon that has a retrograde orbit and might have been captured from the Kuiper Belt.
Triton
a spherical shell of icy bodies surrounding the solar system, the source of long-period comets.
the Oort Cloud
There is a mathematical relationship between a planet’s mean distance from the sun and the time it takes the planet to revolve around the sun (orbital period).(which law)
Law #3: Law of Planetary Periods
defined as the ratio of the distance between the foci to the length of the major axis.
eccentricity