GENERAL SCIENCE - UNIT 4: EARTH IN SPACE (PART 2): Quiz Two|The Sun's Family

Planet

A celestial body moving in an elliptical orbit around a star.

Axis

An imaginary line through a body, about which it rotates.

Asteroid

Any of thousands of small objects that revolve about the sun, chiefly between Mars and Jupiter's orbits.

4

Galileo discovered __ out of Jupiter's 67 known moons.

Largest

Jupiter is the __________ of all the planets.

Elliptical

Most comets travel around the sun in elongated ____________ orbits.

Comet

Orbiting body with a bright center and a cloudy tail of dust which always points away from the sun.

Mars

Planet next in order beyond the Earth. The seventh largest planet, notable for its red color.

Inclined

Pluto's orbit is unique because it is _________.

Perpendicular

Satellites of Uranus orbit ____________ to its equator.

Venus

Sixth largest planet, second from the sun. Orbit nearest to Earth. Often called Evening Star or Morning Star.

Retrograde

The direction of rotation of Venus is _______________ to the direction of the other planets.

Mass

The force of gravity on Mercury is less than the gravity on Earth because Mercury's ________ is less.

False

True or False: Comets have long, indefinite lifespans.

Terrestrial

The four planets nearest the sun, which are somewhat similar to the Earth. These planets are Mercury, Venus, Earth, and Mars. These planets consists mainly of rock, dirt, and minerals.

Jovian

The group of planets including Jupiter, Saturn, Uranus, and Neptune. These planets consist of a metal core, and a thick atmosphere of many gases.

Ultraviolet Radiation

The main component making life on Mars impossible, is that there is no protection against _______________ _____________.

Oxygen

The major compound that is 21% of the Earth's atmosphere is called _________.

Nitrogen

The major compound that is 78% of the Earth's atmosphere is called _________.

Standard

The mass and gravity of the Earth are used as a _______________ of comparison with other planets.

Orbit

The path of an object as it revolves around another object in space.

Mercury

The planet in our solar system nearest the sun.

Uranus

The prediction of Neptune was made possible because of the study of _________.