Chapter 2 Flashcards
What are constellations?
A collection of stars determined by different cultures.
- Not physical groupings
How many constellations are there?
88 (1 per region)
What are angles used for?
Directions
What is the angular size of the moon?
1/2 a degree
1 degree is what?
60 arc-minutes
1 arc-minute is what?
60 arc-seconds
What is the celestial sphere?
A giant dome surrounding the earth.
What is a Zenith?
Points directly above you in the sky.
What is a circumpolar?
Stars that never set or rise.
What is the celestial equator?
Projections of Earth’s equator.
What is the north celestial pole?
The point in the sky about which all the stars seen from the Northern Hemisphere rotate.
How much of the earth is always lit by the sun?
Half of it.
Where do the stars circling the zenith not set or rise?
The North Pole
Where do the stars rise straight up and down?
The Equator
What does the side of the earth facing the sun see?
The sun’s light
What does the side of the earth facing away from the sun see?
The changing positions of the stars.
What do you see at different times of the night?
Different constellations
What changes over a year?
The sun appears to move a fixed set of constellations.
What is the path of the sun called?
The Ecliptic
What are the zodiacs?
Constellations along the ecliptic.
What is the precession?
Long-term change of Earth’s axis.
