Western Washington University   College of Sciences and Technology   Physics/Astronomy Dept.   Bellingham, WA USA
How Big is Big?
This collection of tables provides typical values for the properties of select objects; some natural and some human-made. Some of the values are very well defined, such as the mass of an electron, while others represent an estimated order of magnitude for comparison, such as the size of the Universe. Click the titles for wide ranges of objects and their values.

Mass
The quantity or aggregate of matter that a body possesses.
measured in kilograms
Velocity
The relative speed and direction of the movement of a body.
measured in meters per second
Acceleration
The rate of change of speed or direction of movement of a body.
measured in meters per second squared
Momentum
The property of a body defined by its mass multiplied by its velocity.
measured in kilograms meters per second
Radius
The distance from the center of a curvature to its edge or surface.
measured in meters
Density
The quantity of matter per unit volume of a body.
measured in kilograms per meters cubed