Earth-Sun-Moon System Patterns Flashcards

Why does the Moon appear to change shape over the course of a month?

Answer: Different amounts of the sunlit side of the Moon are visible from Earth

As the Moon orbits Earth, we see varying portions of its sunlit half, creating the appearance of changing phases.

A student notices that the Sun rises earlier each morning for several weeks. What season is most likely approaching?

Answer: Summer

As summer approaches in the Northern Hemisphere, Earth's tilt causes the Sun to rise earlier and set later each day.

What is the term for the point in Earth's orbit when it is closest to the Sun?

Answer: Perihelion

Perihelion is the point in Earth's orbit where it is closest to the Sun, occurring around January 3rd.

During a full moon, where is the Moon located relative to Earth and the Sun?

Answer: On the opposite side of Earth from the Sun

During a full moon, Earth is between the Sun and Moon, so the entire sunlit face of the Moon is visible from Earth.

Which event occurs when day and night are approximately equal in length all over Earth?

Answer: Equinox

During an equinox, Earth's axis is not tilted toward or away from the Sun, making day and night nearly equal in length.

A spring tide occurs when the Sun, Earth, and Moon are aligned. What effect does this have on ocean tides?

Answer: Tides are higher and lower than normal

When the Sun, Earth, and Moon align, the gravitational forces combine to produce spring tides with greater high and lower low tides.

How long does it take the Moon to complete one full orbit around Earth?

Answer: About 27–29 days

The Moon takes approximately 27.3 days to orbit Earth, but about 29.5 days pass between identical phases due to Earth's movement around the Sun.