Effects of the Earth, Sun & Moon on the Calendar, Time Zones, and Seasons + Eclipses, Lunar Phases & Tides

Earth & Space Science

What are days based on?

the Earth’s rotation on its axis

What are months based on?

the Moon’s revolution around the Earth

What are years based on?

the Earth’s revolution around the Sun

What does each vertical line on a timezone map represent the difference of?

one hour

What is the point called when the sun is directly overhead? And what time is it at that point?

The Zenith point, 12:00 pm (noon)

What happens on a timezone map as you head East?

it gets later

What happens on a timezone map as you head West?

it gets earlier

To determine a time zone on the map…

count the time zones to determine the hour and then see if you are going earlier or later by going east vs west

What are seasons caused by?

Earth’s tilt on it’s axis. As it revolves around the sun, the tilt causes each hemisphere to receive more direct exposure at certain times in its orbit

How is the earth pointing during the Winter and Summer Solstice?

when the earth is pointed most directly away from the Sun in the Northern Hemisphere and most directly towards the Sun in the Southern Hemisphere, the North is in its Winter Solstice, and the South is in its Summer Solstice

What happens during Spring and Fall Equinox?

the exposure is about the same in both hemispheres

When do eclipses occur?

when the shadow of the earth or the moon is cast onto the other body

What happens during a lunar eclipse?

the moon is blocked out; the moon and the sun are on opposite sides of the Earth

What happens during a solar eclipse?

the sun is blocked out, the Moon is between the Earth and the Sun

What are lunar phases?

the movement of the moon around the earth (one full revolution around the earth per month)

The part of the moon we see lit depends on…

its relative position to the Earth

New Moon

the moon is almost invisible or very faint, this is because the lit side is facing away from the Earth

marks the beginning of a new lunar cycle

Waxing Crescent

the moon looks like a toenail, it is getting bigger, like a backwards C

Quarter Moon

looks like a half moon, perpendicular to the Earth relative to the Sun

Waxing Gibbous

mostly lit, opposite direction of the sun relative to the earth, getting bigger

Full Moon

fully lit moon, completely opposite the direction of the sun

Waning Gibbous

mostly lit, getting smaller

Quarter Moon

half moon on left, getting smaller

Waning Crescent

forward facing C, toenail, getting smaller

If its high noon and there is a full moon, can you see the moon?

No

What is the exception with the full moon where you may be able to see it?

during dusk or dawn when the sun and full moon are on opposite horizons

What causes tides?

tides are caused by the gravitational pull of the Moon and the Sun on Earth

What is the gravitational pull on the earth of the sun vs the moon?

the moon is so much closer to the Earth, so even though the Sun is bigger, the moon exerts more gravitational pull on the Earth and the Earth bends slightly towards that pull

What part of the earth bends?

all of it- the solid part bends a little, but the ocean bends even more (causing tides)

The oceans rise up towards the moon causing ______.

high tides

Every 24 hours there are…

2 high tides and 2 low tides that correspond with the Earth’s rotation

Spring Tides

when the moon and the sun are in alignment, we get more extreme tides called spring tides

this extreme is because the moon and sun aren’t cancelling each other out at all, they are both pulling strongly in the same direction

Neap Tides

when the moon and sun are pulling at perpendicular angles, we get less extreme tides called neap tides

the sun is cancelling out a little bit of the moon’s efforts/gravitational force