Celestial Coordinates
These two coordinates are the celestial equivalents to latitude and longitude (respectively) on Earth
What are Declination and Right Ascension
This point in the sky is 90 degrees from your horizon
What is your zenith
The imaginary line on the Earth that is the zero point for latitude
What is the equator
Seasons are a direct result of this
What is the tilt of the Earth's axis
The name of the constellations that follow the path of the ecliptic
What are the Constellations of the Zodiac
The apparent path of the Sun along the celestial sphere
What is the ecliptic
The horizontal and vertical (respectively) position of a star can be described by these local coordinates
What are azimuth and altitude
This imaginary line runs through Greenwich, England, and serves as the zero point for longitude on Earth
What is the Prime Meridian
The season in the southern hemisphere when the North Pole is tilted away from the Sun
What is summer
These stars never rise and never set for a given location on Earth
What are circumpolar stars
The direction in which Right Ascension increases
What is eastward
The name of the imaginary line that runs from due north, through your zenith, to due south
What is the Celestial Meridian
The area between 23.5 degrees North and 23.5 degrees South latitudes, which receive more direct sunlight than any other place on Earth.
What are the Tropics
The start of this season in the Northern Hemisphere occurs when the sun is moving northward along the ecliptic as it crosses the celestial equator
What is Spring
The slow wobble of the Earth's axis due to the gravitational pull of the Sun and the Moon.
What is precession
This point on the celestial sphere marks the zero point for Right Ascension
What is the Vernal Equinox
Azimuth starts at due north and continues in this direction
What is eastward
The sexagesimal notation for this decimal coordinate is 77 degrees 30 minutes
What is 77.5 degrees
The day on which an observer at the North Pole sees the sun rise and skim the horizon throughout the course of the day.
What is the Vernal Equinox
When objects transit the celestial meridian, they achieve this
What is highest altitude
This point on the celestial sphere has an RA = 12hrs and a Dec = 0 degrees
What is the Autumnal Equinox
The cardinal direction that is zero degrees altitude and 270 degrees azimuth
What is west
This great circle at 66.5 degrees North latitude marks the northern limit of continuous sunshine during the year.
What is the Arctic Circle
The great circle at 23.5 degrees north latitude, where the Sun is overhead at noon on the summer solstice.
What is the Tropic of Cancer
This is the length of the precession cycle
What is 26,000 years