means "wanderers" in Greek
In 17th Century, he used the telescope to study the planets and stars
includes the sun, the planets, and many smaller objects
made up of the planet Saturn and the several moons that orbit Saturn
average distance between the Earth and the sun; approximately 150 million kilometers (AU)
Until the 17th Century, the universe was throught to hae only ____________.
inner solar system
contains four planets that are closest to the sun.
outer solar system
contains the planets that are farthest from the sun
inner planets that have dense and rocky surfaces
planets that have deep, massive atmosheres rather than hard rocky sufaces. Jupiter, Saturn, Uranus, and Neptune
The only planet of the outer solar system that is small, dense, and rocky.
This is when the plant Uranus was discovered
invention that helped early scientists discover more bodies in the solar system
on this planet, you would only weigh 38% of what you weigh on Earth and a day on this planet would take 59 Earth days.
period of rotation
the amount of time that an object takes to rotate once
the time that a planet takes to go around the sun once
the motion of a body orbiting another body in space
period of revolution
the time an object takes to revolve around the sun once
This planet is more like the Earth than any other planet; it is smaller, less massive and less dense than Earth.
appears to spin in a counterclockwise direction when it is viewed from above the North Pole
a planet that spins in a clockwise direction
carbon dioxide traps thermal energy from sunlight in this process
Venus has the ________ surface of any planet in the solar system (464 degrees).
a spacecraft that mapped the surface of Venus using radar waves in 1990-1992
Venus, like Earth, has ________________.
National Aeronautics and Space Administration
right distance from the sun
_________________ allowed Earth to prevent water from freezing or from boiling away
Perhaps the most studied planet in the solar system (other than Earth)
Mars is a (cold or hot) planet
Viking I & Viking 2
These landed on Mars in 1976 and Mars Pathfinder landed on Mars in 1997.
A large mountain with an extinct shield volcano on Mars
Largest planet in our solar system. Made up of hydrogen and helium
Great Red Spot
a storm system that is ore than 400 years old on Jupiter
2nd largest planet in the solar system. This planet has rings and is still forming
icy particles that range in size from a few centimeters to several meters -- usually surround gas giants
discovered by English amateur astronomer William Herschel in 1781, this planet is tipped over on its side
discovered in 1846, this planet has belts of clouds in its atmosphere
sometimes called the mystery planet, this is the farthest planet from the sun and the smallest planet
Pluto's moon, which is more than half its size
natural or artificial bodies that revolve around larger bodies such as planets
Except for Mercury and Venus, all planets have natural satellites called ______
another name for the Earth's moon