Introduction and The Celestial Sphere

Flashcards for astronomy lecture review.

Universe

The totality of all space, time, matter, and energy.

Astronomy

The study of the universe.

Light-year

The distance light travels in a year (about 6 trillion miles!).

Scientific Theory

Framework of ideas and assumptions used to explain observations and make predictions.

Constellations

Figures having meaning to those doing the grouping; there are 88 recognized ones.

Polaris

Also known as the North Star; directly over Earth’s north rotational pole.

Celestial Sphere

Stars seem to be on the inner surface of a sphere surrounding the Earth.

Transit

Reaches its highest point in the sky and is found on the meridian.

Zenith

The point directly overhead.

Zodiac Constellations

The twelve constellations the Sun moves through during the year.

Ecliptic

The path that the Sun travels along on the celestial sphere throughout the year.

Ecliptic

The apparent annual path of the Sun across the celestial sphere.