Our Moon

An asteroid the size of Mars A molten Earth, 4.5 Billion years ago. Giant impact theory (big smack, big whack, Orpheus theory) The formation of the moon An asteroid the size of Mars Creation of our Moon: 4.5 Billion years ago, the Earth was still forming and not even solid yet when is it was hit with an asteroid about the size of Mars. A huge chunk off the Earth broke, gravity pulled it into a sphere and was pulled into orbit by Earth’s gravity. A molten Earth, 4.5 Billion years ago.

Surface of the Moon: Surface Features Craters- depressions from impacts. Bombardment from meteoroids was mostly 800 million years ago. Rays- lines of ejected materials around craters Rilles- valleys from old lava depressions- similar to lava tubes on Earth Highlands- mountain ranges that surround crater depressions Marias-large dark regions, once believed to be oceans, now known to be old lava pools Ejecta- material blasted out from impacts The rocks of the moon are mainly basalt ( a granite-like rock), a very common igneous rock on the Earth and silicates (silicon and oxygen type rocks) which make-up 96% of Earth’s surface. Surface of the Moon: Maria Rilles Rays Crater Highlands The moon’s surface has been heavily cratered due to its atmosphere being too thin to protect. (too little gravity)

The side that faces us…. Dark Side of the Moon Due to the synchronous rotation and revolution of the Moon, only one side of moon always faces the Earth. We will NEVER see the Dark Side of the Moon from Earth! The Dark Side of Moon….

Lunar Interior Based on the seismic data from the moon, scientists believe the interior of the moon is similar to that of Earth; crust, upper mantle, lower mantle, and core. The upper mantle is solid (therefore, no plate tectonics) and the lower mantle is partially molten. Core is solid iron.

History of the Moon: Radioactive dating of rock collection from the moon show the age of lunar rocks to be 3.8 to 4.5 billion years old, supporting the Impact Theory for the formation of the moon. The majority of the moons impact craters were created 800 million years ago during a period of heavy asteroid bombardment.

Description and Size of the Moon The moon is small with a diameter about the distance from New York to San Francisco. 1.2% the mass of the Earth 238,900 miles (384,400 km) from the Earth Due to the lacking of an atmosphere, the moon temperature in sunlight is 127°C but drops to -173°C when there is no sunlight! Description and Size of the Moon Albedo is the percentage of light that is reflected by an object. The moon’s albedo is 7% compared to 31% of Earth. Moon’s atmosphere is extremely thin weighing only 22,000lbs.

The moon acts like a large mirror, reflecting the light from Sun, creating lunar phases. New Moon - When the moon is between the Earth and Sun. Therefore the light reflected is on the side of the moon that is not facing us and we do not see the moon. As the moon revolves around us, the amount of sunlight reflected increases. This increase in light is called “waxing”. Full Moon - when the Earth is between the moon and Sun. The moon is fully reflective of the sun. After the full moon, the amount of light reflected decreases, this is called “waning”. Lunar Phases “Moonth” or month is the time that it takes for the moon to complete its phases, which is 29.5 days.

Middle Beginning Lunar Phases

Lunar Orbit Eclipses do NOT occur every month because the moon’s orbit is tilted and only aligns occasionally for eclipses to occur. Perigee- point when the moon is closest to Earth. Apogee- Point when the moon is furthest away from Earth.

Lunar Influence The moon’s pull on the Earth cause the shift of our tides The Earth’s gravity on the moon causes shaking of the lunar surface called moonquakes

Spring and Neap Tides Spring Tides -larger than usual high and low tides due to the moon and sun being perfectly aligned and pulling equally on our oceans. Occurs during full and new moon phases. Neap Tides- lower than usual high and low tides due to the sun and moon being at a 90° angle and working against each other. Occurs during first and last quarter phases.

Eclipses An eclipses is a blocking of sunlight to the Earth. Solar Eclipses- when moon is directly between Earth and Sun. Lunar Eclipse – when the Earth is between the Sun and Moon. Umbra- the darker part of a shadow. Penumbra- the lighter part of a shadow. Average time for an eclipse is 2-3 minutes, 7.5 maximum.

Lunar Eclipse Occurs when the moon passes into the Earth’s shadow or umbra. Lunar eclipses usually occur about two weeks after a solar eclipse. Lunar eclipses occur during a full moon and the moon appears a reddish-orange color. The moon appears this color due to the refraction of light off the particles in the Earth’s atmosphere.

Solar Eclipse When the Moon blocks the light from the sun. The sun is 400 times larger than the moon but the moon is 400 times closer, therefore appears to be about the same size. The sun’s Corona is exposed. Occurs during a new moon. The moon’s shadow falls on the Earth. Causes momentary darkness on Earth but can only be seen on very small regions of the planet because the moon’s shadow is so small compared to our planet. Next Solar Eclipse - May 20, 2012 -It will only last for 5 minutes!!!

Sun-Earth-Moon System The Earth’s tilt of 23.5° causes our seasons on Earth. When the Earth is tilted TOWARDS the sun, Summer in Northern Hemisphere, when tilted AWAY from sun, winter in the Northern Hemisphere Solstice: period when the Sunlight is reflected furthest from the equator. Summer Solstice June 21st , maximum amount of sunlight. Winter Solstice December 21st, minimum amount of sunlight Equinox: When the Earth’s axis is perpendicular to the sunlight (equal amounts of sunlight in Northern and Southern Hemisphere) September 23rd March 21st http://sports.espn.go.com/espn/eticket/story?page=tundra

Reason for the Seasons:

The many moons of our Solar System

Why will Neil Armstrong’s footprints never change on the moon? Lunar Landings: Only 12 people have ever set foot on the Moon. July 20, 1969 Apollo 11 makes first human landing on the moon. Apollo 12, 14, 15, 16 and 17 all have landed on the moon collecting samples, explored highlands and mares. Now, scientists are researching ways to put a permanent manned outpost on the surface of the moon. http://www.guardian.co.uk/science/video/2009/jul/02/apollo-11-buzz-aldrin http://www.guardian.co.uk/science/video/2009/jul/15/apollo-11-planting-the-flag Why will Neil Armstrong’s footprints never change on the moon? Video: Neil Armstrong sets foot on the moon | Science | guardian.co.uk

Water on the moon! On October 9th 2009, Nasa bombed the moon in a search for H2O! The aim of the $79 million mission was to send two spacecraft — a spent rocket stage down into a crater near the moon's south pole at about 5,600 mph (9,000 kilometers per hour) and see if the impacts threw up water ice. Results showed over 24 gallons of water in this ONE CRATER! After cleaning, this water would be completely drinkable! http://www.msnbc.msn.com/id/33918160/ns/technology_and_science-space/   http://www.msnbc.msn.com/id/21134540/vp/33919791#33919791