AST Final 1 Flashcards
speed of light =
fastest thing in the universe
Astronomical unit (AU)
average distance between Earth and Sun
1 AU =
1.5 x 10^8 km
Light year
distance light travels in a year
1 ly =
9.5 x 10^12 km
Parsec
distance where parallax angle = 1 degree
1 pc =
3.1 x 10^13
Age of universe
13.8 billion years
Age of the solar system:
4.6 billion years
Altitude
height in the sky
azimuth =
east/west location
zenith =
directly overhead observer
celestial sphere
north celestial pole
south celestial pole
celestial equator
ecliptic =
Sun’s path through the sky throughout the year
Polaris =
Northern star (closest to the celestial pole)
this changes are due to precessions
altitude of Polaris =
your latitude
seasons are caused by
earths tilted axis
zodiac sign =
what constellation is behind the Sun at noon on that day
How long is the Moon cycle?
4 weeks
What are the moon phases based on?
which part of the Moon is reflecting sunlight vs facing toward us
solar eclipse:
new moon
