TODAY’S AGENDA

Week 16 Monday May 4, 2015Due Friday may 8HW #16 Astronomy vocab

Notes #7 Earth, Moon and Sun

Fill in the moon phase calendar for today

Moonrise: 5:56 pmMoonset: 7:12amMoon phase: 100% FULL MOON

3% full

13% full17 % full37% full

Important datesImportant dates

May 14- chemistry unit exam

NOT OPEN NOTE

• June 2- Astronomy Unit exam

OPEN NOTE

Notes #7 Notes #7 Earth, moon and SunEarth, moon and Sun

The Earth, Moon and SunThe Earth, Moon and Sun

How does the earth move?How does the earth move?

1. It rotates on its axis

• Rotation Causes day and night

• Earth takes about 24 hrs. to complete 1 rotation

How does the earth move?How does the earth move?

2. It revolves around the sun

•takes 365 1/4 days. This is what makes our Earth year

How does Earth stay in orbit?How does Earth stay in orbit?

1. Gravity:

The force that attracts all objects toward each other.

How does Earth stay in orbit?How does Earth stay in orbit?

Gravity depends on:Gravity depends on:massmass and and distancedistancea. a. greatergreater mass has mass has greatergreater gravity gravityb. greater distance means less b. greater distance means less gravitygravity

How does Earth stay in orbit?How does Earth stay in orbit?

2. Inertia: objects move in a straight line until acted on by an outside force

Sketch the forces that keep Earth in orbit

Path of inertia

What causes the seasons?What causes the seasons?

• The earth is tilted as it revolves around the sun.

Sunlight Striking Earth’s SurfaceSunlight Striking Earth’s Surface• Near the equator, sunlight strikes Earth’s surface

more directly and is less spread out than near the poles.

Seasons on EarthSeasons on Earth• The height of the sun above the horizon

varies with the season.

How does the moon move?How does the moon move?

1. It rotates- once every 27 days

2. It revolves around the Earth about every

29 days

What causes moon phases?What causes moon phases?

The phase we see dependson how much of the lit side is visible from earth

New moon- sunlit side of moon New moon- sunlit side of moon faces away from Earthfaces away from Earth

Crescent- Crescent- less than half of the less than half of the sunlit side of the moon is visiblesunlit side of the moon is visible

Quarter: Quarter: half of the sunlit side of half of the sunlit side of the moon is visiblethe moon is visible

Gibbous: Gibbous: more than half of the more than half of the sunlit side of the moon is visiblesunlit side of the moon is visible

Full moon- the entire sunlit portion Full moon- the entire sunlit portion of the moon is visibleof the moon is visible

• Waxing: moon is getting “bigger”:

• Waning: moon is getting “smaller”.

What is a lunar eclipse?What is a lunar eclipse?

• Lunar Eclipse: happens Earth is directly between sun and moon

• Can only happen in FULL MOON stage

• Insert eclipse video here

Lunar EclipseLunar Eclipse

• End here

• Insert total eclipse of the sun

Solar EclipseSolar Eclipse

• When the shadow of the moon falls on the Earth

• How often do they occur? When the moon passes directly between the Earth and the sun. ONLY DURING A NEW MOON PHASE

• How long do they last? A FEW MINUTES

• ONLY VISIBLE IN A NARROW PATH

Solar eclipseSolar eclipse