Earth in Space

Earth in Space

Space Ch 1 L 2 p. 10-17

How Does Earth Move?

• Earth moves in space in two major ways: rotation and revolution.

• Rotation: is the spinning of Earth on its axis.

• Earth’s axis is an imaginary line that passes through Earth’s center and the North and South Poles.

• The rotation of Earth causes day and night.

Multiple Choice

What is the spinning of Earth on its axis?

• Rotation

• Revolution

Multiple Choice

What is an imaginary line that passes through Earth’s center and the North and South Poles?

• Rotation

• Revolution

• Pole

• Axis

Multiple Choice

Rotation causes what?

• A year

• Day and Night

• Seasons

How Does Earth Move?

• Revolution: is the movement of one object around another.

• One revolution of Earth around the sun is one year.

• Earth’s path, or orbit, around the sun is an ellipse.

• The ellipse brings the planet closest to the sun in January.

Multiple Choice

What is the movement of one object around another?

• Rotation

• Revolution

• Axis

• Pole

Multiple Choice

One _____________ of Earth around the sun is one year.

• Rotation

• Revolution

Multiple Choice

How long does it take earth to make on complete revolution of the sun?

• 24 hours
• 1 day
• 365 days
• 365.25 days

Multiple Choice

What's another word for orbit?

• Path

• Movement

• Poles

How Does Earth Move?

• People of many cultures have used the motions of Earth and the moon to establish calendars.

• A calendar is a system of organizing time that defines the beginning, length, and divisions of a year.

Multiple Choice

What is a system of organizing time that defines the beginning, length, and divisions of a year?

• Calendar

• Planner

• Religion

• Beliefs

What Causes Seasons?

• Near the equator, sunlight hits Earth’s surface from almost overhead.

• Near the poles, sunlight arrives at steep angle.

• As a result, near the poles sunlight is spread out over a greater area.

• That’s why it is warmer near the equator that near the poles.

Multiple Choice

Why is it warmer at the equator than the poles?

• The sunlight hits almost directly overhead

• The sunlight his a larger surface area

• The sunlight hits at a steep angle

Multiple Choice

The tilt of the earths axis:

• 5 degrees
• 10.2 degrees
• 23.5 degrees
• 365.25 degrees

What Causes Seasons?

• If Earth’s axis were straight up and down relative to its orbit, temperatures in an area would remain fairly constant year-round.

• There would be no seasons.

Multiple Choice

If Earth had straight axis what would happen?

• The sunlight would hit the same year-round, there would be no seasons.

• The sunlight would hit at different angles, and there would still be seasons.

What Causes Seasons?

• However, Earth’s axis is titled at an angle of 23.5 degrees from the vertical.

• So as Earth revolves around the sun, the north end of its axis is tilted away from the sun for part of the year and toward the sun for part of the year.

• Earth has seasons because its axis is tilted as it resolves around the sun.

Multiple Choice

Earth has seasons because its axis is _________ as it resolves around the sun.

• tilted

• straight

• moves

• curves

What Causes Seasons?

• The sun appears farthest north or south of the equator twice each year.

• Each of these days is called a solstice.

Multiple Choice

When the sun appears farthest north or south of the equator twice each year what is it called?

• solstice

• equinox

What Causes Seasons?

• In the Northern Hemisphere, the summer solstice occurs around June 12.

• That is the longest day of the year in the Northern Hemisphere and the shortest day in the Southern Hemisphere.

Multiple Choice

In the Northern Hemisphere, June 12th is known as the what?

• Summer Solstice

• Summer Equniox

What Causes Seasons?

• Similarly, around December 21, the winter solstice occurs in the Northern Hemisphere, while the summer solstice occurs in the Southern Hemisphere.

• Halfway between the solstices, neither hemisphere is tilted toward the sun.

• Each of these days is called an equinox.

• On an equinox, the noon sun is directly overhead at the equator, rises due east, and sets due west.

Multiple Choice

What is it called when halfway between the solstices, neither hemisphere is tilted toward the sun?

• Solstice

• Equinox

• All sunlight day

Multiple Choice

In the Northern Hemisphere, December 21st is known as the what?

• Summer Equinox

• Winter Equinox

Review Time

Time to see what you have learned!

Multiple Choice

What is the spinning of Earth on its axis?

• Rotation

• Revolution

Multiple Choice

What is an imaginary line that passes through Earth’s center and the North and South Poles?

• Rotation

• Revolution

• Pole

• Axis

Multiple Choice

Rotation causes what?

• A year

• Day and Night

• Seasons

Multiple Choice

What is the movement of one object around another?

• Rotation

• Revolution

• Axis

• Pole

Multiple Choice

One _____________ of Earth around the sun is one year.

• Rotation

• Revolution

Multiple Choice

How long does it take earth to make on complete revolution of the sun?

• 24 hours

• 1 day

• 365 days

• 365.25 days

Multiple Choice

What's another word for orbit?

• Path

• Movement

• Poles

Multiple Choice

What is a system of organizing time that defines the beginning, length, and divisions of a year?

• Calendar

• Planner

• Religion

• Beliefs

Multiple Choice

Why is it warmer at the equator than the poles?

• The sunlight hits almost directly overhead

• The sunlight his a larger surface area

• The sunlight hits at a steep angle

Multiple Choice

The tilt of the earths axis:

• 5 degrees

• 10.2 degrees

• 23.5 degrees

• 365.25 degrees

Multiple Choice

If Earth had straight axis what would happen?

• The sunlight would hit the same year-round, there would be no seasons.

• The sunlight would hit at different angles, and there would still be seasons.

Multiple Choice

Earth has seasons because its axis is _________ as it resolves around the sun.

• tilted

• straight

• moves

• curves

Multiple Choice

When the sun appears farthest north or south of the equator twice each year what is it called?

• solstice

• equinox

Multiple Choice

In the Northern Hemisphere, June 12th is known as the what?

• Summer Solstice

• Summer Equniox

Multiple Choice

What is it called when halfway between the solstices, neither hemisphere is tilted toward the sun?

• Solstice

• Equinox

• All sunlight day

Multiple Choice

In the Northern Hemisphere, December 21st is known as the what?

• Summer Equinox

• Winter Equinox