Chapter 27 (Earth Science)

Dark, smooth plains on the Moon's surface

Time during which the sunlit side of the Moon that is visible begins to decrease

The number of waves or oscillations that pass a point in a second

The farthest point in the Moon's orbit from Earth

The closest point in the Moon's orbit to Earth

The increase in the visible sunlit surface of the Moon

When the sun is overhead at its farthest distance either north or south of the equator

A technique that uses images from several telescopes to produce a single image

What causes solar eclipses?

The outer portion of shadow, where some light still reaches

What was the first man-made satellite?

When the Earth is midway between solstices, it means equal nights

Material that is blasted out during impacts and falls back to the surface

The sequential changes in the appearance of the Moon

The percentage of incoming sunlight that a surface reflects

What is the best known space observatory?

State at which orbital and rotational periods are equal

Who was the first man in space?

Heavily cratered regions of the moon that are light in color and mountainous

When the moon is between the Earth and the Sun the illuminated side is not visible from Earth

Long trails of ejecta that radiate outward from impact sites

Phase during which the entire sunlit side of the Moon faces Earth

The radiation from distant bodies throughout the universe

The inner, cone-shaped portion of shadow which blocks all direct sunlight

The distance between the peaks on a wave

What causes the apparent rising and setting of the Sun?

Meandering, valleylike structures that might be collapsed lava tubes

At what degree is the Earth tilted on its axis?