Relative Sizes
(Earth, solar system, Milky Way galaxy, local super cluster, universe)
Relative Distances
- If the sun shrank to 1mm (grain of sand) then earth would be 11cm away, Pluto would be 4 meters and the nearest star would be ajax
- If the entire solar system shrank to 1mm one side of the milky way would be at London, Ontario and it would end at Montréal
- If the milky way shrunk to 1mm the nearest galaxy would be 2.5cm away and the nearest cluster would be 50cm away
Common Distance Units Used in Astronomy
Astronomical Unit (AU): Defined to be the average distance between the Earth and the Sun (1 AU). This unit is commonly used to describe distances within the solar system (i.e. Neptune is 30 AU from the sun)
The Lightyear (ly): One light year is defined to be the distance light travels in a year. Commonly used to describe the distances within the Milky Way Galaxy. (i.e. The nearest star to the sun is 4 ly away)
