Astronomy Review Part 1

For timekeeping purposes, for timing agriculture (planting and harvesting), for astrology or religion, for historical record keeping, all of the above.

Heliocentric Model.

John Glenn.

A group of constellations lying near the ecliptic.

Geocentric.

To observe distant celestial objects.

A planet orbits a star and does not produce its own light, while a star generates light and heat through nuclear fusion.

It is the plane of Earth's orbit around the Sun, where most planets' orbits lie.

A unit of distance that represents how far light travels in one year, approximately 5.88 trillion miles.

The leading explanation for the origin of the universe, proposing it began from a singularity and has been expanding ever since.