Astronomy
• The study of planets, stars and other objects in outer space
Astronomical Unit(AU)
The unit of measure equal to the distance from the SUN to the EARTH. AU’s are used to measure distances INSIDE the solar system
Distance from the Earth to the
Sun = 1 AU92,955,807 miles
Light YearLight years are used to measure distances outside of our solar
system
Distance light travels in one year.
1 light year= 5,878,499,810,000
miles
Rotation
• An object spins on its axis; It causes day and night. Earth rotates once every 24 hours.
Revolution
• An object goes around another object; It causes seasons. Earth revolves once every year (365.25 days).
Orbit
• It is the curved path the planets follow around the Sun.