Concept
Celestial Poles
Where Earth's spin axis meets the sky.
The two points on the celestial sphere about which the stars appear to rotate — close to Polaris in the north, with no bright star in the south.
Overview
The two points on the celestial sphere about which the stars appear to rotate — close to Polaris in the north, with no bright star in the south.
See also
Black Holes
Regions where gravity stops light itself.
The Habitable Zone
Where liquid water can exist on a planet's surface.
Termination Shock
Where the solar wind slows from supersonic to subsonic.
Milankovitch Cycles
Slow orbital changes that drive Earth's ice ages.
Lagrange Points
Five spots where gravity and orbital motion balance.
Photon Sphere
Where light itself can orbit a black hole.