Galaxy clusters

Question 1

local group

Answer 1

loose galaxy cluster (includes milky way)

Question 2

gravitational lensing

Answer 2

general relativity - light bends due to massive objects in path

Question 3

tully fisher relation

Answer 3

relation between 21 cm line and luminosity of galaxy

Question 4

cosmological redshift

Answer 4

distance proportional to velocity

Question 5

great attractor

Answer 5

local group moving towards virgo cluster - virgo cluster moving towards even bigger cluster