Speed of Light, Light Years and AU
Vacuum
A space that is void of matter, or anything. In a science lab, a sealed vacuum tube, bottle or chamber is used to create the environment in which there is no matter, or external influence on a tested object of specimen.
Light Year
A unit of astronomical distance equivalent to the distance that light travels in one year. This is about 6 trillion (6,000,000,000,000) miles. This measurement unit is used outside of our solar system.
Measurement of distance in space in our galaxy - the Milky Way
In our solar system, the Milky Way, the distance in space is measured in AU - Astronomical Units
Speed of Light
Light travels at the same speed in a vacuum. That is about 300 million (299,792,458) meters per second. That is really fast, but due to the great distance between objects in space, it still takes time. It takes about 8 minutes for light to travel from the Sun to the Earth. However, it takes light about 4 years to travel from the Sun to the next nearest star.
AU - Astronomical Units
The way that distance in space in our solar system is measured. One AU is equal to the distance of about 93 million (92,955,807) miles. Our Earth is about one (1) AU from the Sun.
