BCS9 Chapter 10

Question 1

astronomers

Answer 1

people who study objects in space

Question 2

Big Bang theory

Answer 2

the theory that proposes that the universe formed approximately 13.7 billion years ago when an unimaginably tiny volume of space suddenly and rapidly expanded to immense size

Question 3

celestial bodies

Answer 3

all the objects in space, including the Sun, the Moon, planets, and stars

Question 4

cosmological red shift

Answer 4

wavelengths of radiated light that are being constantly stretched (lengthened) as the light crosses the expanding universe

Question 5

electromagnetic radiation

Answer 5

energy that is carried, or radiated, in the form of waves that range in length from short to long; types include X rays, ultraviolet radiation, visible light, microwaves, and radio waves

Question 6

red shift

Answer 6

a shifting light from an object toward the red (longer wavelength) end of the spectrum as the object moves away from Earth.

Question 7

spectroscope

Answer 7

an optical instrument that acts like a prism to separate light into its basic component colours

Question 8

elliptical galaxy

Answer 8

one of the three basic galaxy shapes; a galaxy that ranges shape from a perfect sphere to an elongated but flattened ellipse and contains some of the oldest stars in the universe

Question 9

irregular galaxy

Answer 9

one of three basic galaxy shapes; a galaxy that has neither spiral arms nor an obvious central core, made up of a mix of newly forming stars and old stars

Question 10

nebula

Answer 10

a cloud of gas and dust in space

Question 11

spiral galaxy

Answer 11

one of three basic galaxy shapes; a galaxy with many long “arms” spiralling out from a centre core made up of stars that formed long ago

Question 12

star cluster

Answer 12

a distinct formation of stars in a galaxy; the two types are open clusters and globular clusters