CHAPTER 11 VOCAB

Question 1

asteroid

Answer 1

millions of small, rocky objects that orbit the sun in the asteroid belt between mars and jupiter

Question 2

comet

Answer 2

made of gas, dust, and ice and moves around the sun in an oval-shaped orbit (elliptical)

Question 3

astronomical unti

Answer 3

average distance from earth to the sun

Question 4

period of revolution

Answer 4

the time it takes an object to travel once around the sun

Question 5

period of rotation

Answer 5

the time it takes an object to make one complete rotation around itself

Question 6

our star

Answer 6

the sun, it is the center of our solar system

Question 7

sun

Answer 7

an object in space made of gases which nuclear fusion reactions occur that emit energy

Question 8

orbit

Answer 8

an object path around the sun

Question 9

planets

Answer 9

spherical objects that orbit around the sun and cleared their neighborhood

Question 10

dwarf planet

Answer 10

spherical objects that orbit around the sun, but not have cleared the neighborhood and is not a satellite

Question 11

terrestrial planet

Answer 11

planets closest to the sun, they are made up of rock and metal, and have solid outer layers

Question 12

inner planets

Answer 12

mercury, venus, earth, and mars

Question 13

outer planets

Answer 13

jupiter, saturn, uranus, and neptune

Question 14

greenhouse effect

Answer 14

occurs when a planet’s atmosphere traps solar energy and causes the surface temperature to increase

Question 15

gas giant

Answer 15

outer planets made of hydrogen and helium, they have thick gas and liquid layers covering a solid core

Question 16

galilean moon

Answer 16

four largest moons of jupiter: io, europa, ganymede, and callisto. they are all made of rock and ice

Question 17

meteoroid

Answer 17

small, rocky particle that moves through space

Question 18

meteor

Answer 18

streak of light in earth’s atmosphere made by a glowing meteoroid

Question 19

meteorite

Answer 19

meteoroid that strikes a planet or moon

Question 20

impact crater

Answer 20

round depression formed on the surface of a planet, moon, or other space object by the impact of a meteorite

Question 21

short-period comets

Answer 21

comets that takes less than 200 earth years to orbit the sun

Question 22

long-period comets

Answer 22

comets that take more than 200 earth years to orbit the sun

Question 23

satellite

Answer 23

can be natural or man-made object that is in orbit