Vocabulary
What is the name for the distance from Earth to the Sun that scientists use a unit?
Astronomical Unit (AU)
True or false? Every object has gravity.
True!
Which 4 planets are rocky and dense?
Mercury
Venus
Earth
Mars
Give a definition of the word ORBIT
The path one object takes around another object.
Name one gas giant.
Jupiter, Saturn, Uranus, or Neptune
Diameter
If an object's mass increases, what happens to its gravitational pull?
The gravitational force would increase.
Which 4 planets are made of gas?
Jupiter
Saturn
Uranus
Neptune
What central object do all 8 planets orbit?
The Sun
Name the planets in order, starting with Mercury.
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune
What do scientists call a natural object that orbits a planet?
Satellite
What is "weight"?
A measurement of the pull of gravity.
93 million miles
What do we call an object orbiting a planet?
A satellite (or moon)
What is longer on Venus, a day or a year?
A day.
What is an orbital period and what unit of time does that give us?
One revolution around the Sun.
One year.
What are the two factors that affect the strength of gravitational pull?
Mass and Distance
True or False: The farther a planet is, the faster its orbital velocity.
FALSE!!
Why does a planet that is far from the Sun have a longer orbital period than a planet that is close to the Sun?
A planet that is far from the Sun has a longer distance to travel than a closer planet.
What planet has the most moons? Why?
Jupiter has the most moons because it is the largest planet and has the strongest gravitational force.
What is mass?
The amount of matter in an object.
Why do larger planets tend to have more moons?
Larger planets have more mass and more gravitational pull.
What kind of composition are the outer planets?
Gas
What is the shape of an orbit called?
An ellipse
What is a rotation? What is a revolution? Stand up and demonstrate. Be safe.
Rotation is a planet spinning on its axis.
Revolution is a planet making an orbit around another object.