HOW BIG IS BIG?

This collection of tables provides typical values for arbitrarily selected objects and events. Some values are very well defined, such as the mass of an electron, while others are much more subjective, such as the radius of the Universe. The more subjective values are not meant to be definitive but generally represent accepted orders of magnitude.

Simply click on the folder tabs at the top of the page to access the tables.

Mass: (kg) a quantity or aggregate of matter that a body possesses as evidenced by inertia.

Velocity: (m/s) the relative speed and direction of a body.

Acceleration: (m/s2) the rate of change of the speed or direction of a body.

Momentum: (kgm/s) the property of a body defined by its mass multiplied by its velocity.

Radius: (m) the length of a straight line from the center of a circle or sphere, to its edge or surface.

Density: (kg/m, kg/m2, kg/m3) the quantity of matter per unit length, area, or volume.