Solar System

Question 1

Nebula

Answer 1

a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.

Question 2

Solar Nebula

Answer 2

describes the formation of our solar system from a nebula cloud made from a collection of dust and gas.

Question 3

Nuclear Fusion

Answer 3

a nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.

Question 4

Sunspot

Answer 4

a spot or patch appearing from time to time on the sun’s surface, appearing dark by contrast with its surroundings.

Question 5

Astronomical Unit

Answer 5

The mean distance between the Earth and the sun, about 98 million miles or 150 million kilometers

Question 6

Terrestrial Planets

Answer 6

a planet that is composed primarily of silicate rocks or metals

Question 7

Prograde Rotation

Answer 7

for both rotating and orbiting bodies is in a counterclockwise direction when viewed from a vantage point above the Earth’s north pole.

Question 8

Retrograde Rotation

Answer 8

All eight planets in the Solar System orbit the Sun in the direction that the Sun is rotating

Question 9

Gas Giant

Answer 9

a large planet of relatively low density consisting predominantly of hydrogen and helium, such as Jupiter, Saturn, Uranus, or Neptune.

Question 10

Satellite

Answer 10

an artificial body placed in orbit around the earth or moon or another planet in order to collect information or for communication.

Question 11

Phase

Answer 11

a physically distinctive form of matter, such as a solid, liquid, gas or plasma

Question 12

Eclipse

Answer 12

an obscuring of the light from one celestial body by the passage of another between it and the observer or between it and its source of illumination.a

Question 13

Comet

Answer 13

a celestial object consisting of a nucleus of ice and dust and, when near the sun, a “tail” of gas and dust particles pointing away from the sun.a

Question 14

Asteroid

Answer 14

a large, irregularly shaped object in space that orbits our Sun

Question 15

Asteroid Belt

Answer 15

the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter

Question 16

Meteoroid

Answer 16

a small body moving in the solar system that would become a meteor if it entered the earth’s atmosphere.

Question 17

Meteorite

Answer 17

a meteor that survives its passage through the earth’s atmosphere such that part of it strikes the ground. More than 90 percent of meteorites are of rock, while the remainder consist wholly or partly of iron and nickel.

Question 18

Meteor

Answer 18

a small body of matter from outer space that enters the earth’s atmosphere, becoming incandescent as a result of friction and appearing as a streak of light.