Astronomy Basics Quiz

Star Trails

• Star trails are caused by Earth's rotation.

Celestial Navigation

• Polaris is near the center of the concentric star trail circles.

Seasons

• The summer solstice occurs when the Sun is highest in the sky.
• Seasons are caused by the tilt of Earth's axis as it orbits the Sun.

Observer's Meridian

• An observer's meridian is an imaginary North-South line in the sky that runs through the zenith.

Parallax

• Parallax is the apparent shift of an object due to a change in the observer's location.

Occam's Razor

• Occam's razor states that the best scientific theories have the fewest assumptions (simplest explanations).

Constellations

• We see different constellations in summer and winter because Earth orbits the Sun.

Moon Phases and Times

• If the Moon rises at noon, it is a first quarter moon.
• A full moon sets at dawn.
• A new moon is the phase of the moon for solar eclipses.

Eclipses

• Solar eclipses occur when the Moon's shadow falls on Earth.
• If the Moon's orbit were smaller, total solar eclipses would occur more often.

Angular Size

• If the Sun's size doubled, its angular size would increase to 1.06 degrees.
• The Moon's angular size is approximately 0.5 degrees. If it were twice as far away, its angular size would be 1 degree.

Moon Rotation

• The Moon rotates once per month, keeping one side always facing Earth.

Earth Rotation and Length of Day/Night

• If Earth rotated twice as fast, the night would be shorter.

Lunar Phases

• Lunar phases in order: new moon, waxing crescent, first quarter, waxing gibbous...

Temperature and Season

• Summer is warmer than winter due to the sun being higher in the sky and longer days.

Horizon Coordinate System

• The maximum altitude angle of a star, in the horizon coordinate system, is 90 degrees.