Concept
Ecliptic
The Sun's apparent annual path across the sky.
The plane of Earth's orbit projected onto the sky, along which the Sun, Moon and planets appear to move.
Overview
The plane of Earth's orbit projected onto the sky, along which the Sun, Moon and planets appear to move.
See also
Heliopause
The edge of the Sun's bubble in space.
Solar Time
Time measured by the Sun's position.
Parallax
Apparent shift of a nearby object against a distant background.
Proper Motion
A star's drift across the sky over years.
Bolometric Magnitude
Brightness across all wavelengths.
The Big Bang
How everything began, 13.8 billion years ago.