The Sun, Earth and Moon

Sun facts It would take 109 earths or almost 10 Jupiters lined up, edge to edge, to fit across the sun. The sun is about 330,000 times more massive than earth and 1048 times the mass of Jupiter. The sun makes up 99% of the total mass of the solar system. The density of the center of the sun is 1.50x105 kg/m3, which is 13 times the density of lead.

Layers of the sun Inner Core: (1.5x107°C)-Nuclear Fusion occurs creating energy. Radiative zone: energy is transmitted through radiation. Convective zone: area of convection currents where the heat is constantly Photosphere-(6000 °C)the visible surface of the sun, the two outmost layers are transparent Chromosphere-(10,000°C)the chromosphere appears red, is only visible during a solar eclipse and releases most UV radiation Corona-(over 1 million °C)is fully exposed during a solar eclipse and emits x ray radiation

Sun’s composition and energy: The sun is made up of mostly hydrogen (70.4%) and helium(28%) with less than one percent made up of oxygen, carbon and other trace gases.

Nuclear Fusion Fusion comes from the core of the Su , where pressure and temperatures are extremely high. The process by which hydrogen atoms(light weight atomic nuclei) are converted in to helium atoms and release an enormous amount of energy. The mass of the fused helium is less than the combined mass of four hydrogen atoms, which means mass is lost during the process of nuclear fusion. According to Einstein's famous formula (E=mc2), the lost mass is converted into energy. At the current rate of the Sun’s conversion in nuclear fusion, the sun is about half way through its life cycle with about 5 billion years remaining. So the Sun used about 3% of its hydrogen. *Every second 4.5 million tons of solar mass is converted to radiant energy in the core of the sun.

Life Cycle of Our Sun Our Sun has lived almost 5 billion years of its life and will lived approximately 5 billion more as a medium star. Due to a decreases in atomic fuel, in about 4 billion years our Sun will begin to increase in temperature. Then it will expand and cool to a Red Giant in 5 billion years. In around 10 billion years from now, our Sun will become a hot white dwarf then most likely burn out as a Black Dwarf. Because of their internal structure, a star only burns about 10% of it totally H and He.

Orbits around the sun and moon The Earth’s orbit around the Sun, as well as the moon around the sun, is an “ellipse”, flattened oval. This causes us to have moments when we are closing to or further away from the sun. The Earth-Sun distance varies by about 3%, or roughly 5 million km (3 million miles), over the course of a year. Aphelion- point when the Earth furthest away from the sun (July) *Remember “A” for “Away” Perihelion-point when the Earth is closest to the sun. (January) Apogee-point when moon is furthest away form the earth Perigee-point when the moon is closest to earth

Sun-earth-moon system The sun rises in the east and set in the west, as do the moon, stars and planets due to the earth’s rotation. As the earth rotates, it takes the earth about 4 minutes than 24 hours to complete the rotation. The moon rises and sets 50 minutes later each day because the Moon moves 13° in its orbit over a 24 hour period, and Earth has to turn an additional 13° for the Moon to rise. Barycenter is the central mass of the earth that pulls on the moon. Due to spherical shape of the moon, the barycenter shifts, causing the Moon to “wobble” throughout its orbit. The wobble causes the moon to only line up yearly for eclipses rather than monthly.

Reason for seasons The earth’s elliptical plane(orbit) allows the earth to travel around the sun on at 23.5°tilt, which causes our seasons on earth. When Tilted towards the sun:(aphelion) Sunlight on or above Tropic of cancer Summer in north Winter in south 24 hours of sunlight in arctic When Tilted away from the sun:(perihelion) On or above Tropic of Capricorn Summer in the south Winter in the north 24 hours of sunlight in Antarctic Tropic of Cancer Equator Tropic of Capricorn

seasons Solstice-when the sun is overhead at its furthest distance either north or south. Tropic of Cancer= summer in north Summer solstice-(Around June 21)Longest day of year with most sunlight, first day of summer Winter Solstice (around December 21) shortest day of the year and first day of winter Equinox-midway in orbit between solstices and equal hours of day and night Vernal Equinox (around March 21) first day of spring Autumnal Equinox (around September 21) first day of fall C. Zenith-is the sun’s maximum height at midday. It varies throughout the year, depending on viewer’s location At equinox, zenith appears lower Winter solstice is its lowest position

Sun’s exterior Corona Solar Prominence Sunspot Solar Flare Solar wind

Solar Prominence Solar prominences are large arch of ejected gas from the chromosphere. These often have a twist and occasionally become unstable, ejecting plasma and magnetic flux out from the sun. The prominences are associated with sun’s magnetic field.

Sunspots These are darker, cooler areas on the surface of the sun created by disturbances in the sun’s magnetic field. They may be as small as 16 kilometers or as large 160,00kilometers but usually around twice the size of the Earth. Usually around 4500°C. Activity on our Sun varies over a roughly 11-year cycle. At the beginning of a cycle, sunspots are sparse. The spots gradually increase over several years, peak, and then decrease over the next several years, with spots from old and new cycles often occurring simultaneously as a new cycle starts. At the end of October 2008, another batch of sunspots appeared, most of them belonging to a new cycle!

SOLAR WIND Earth’s Magnetosphere Solar wind is the gas and charged particles that flows outward from the corona at high speed of 400km/s Earth’s Magnetosphere: The Earth’s invisible magnetic field. This field attract solar particles from the sun that could destroy all life on Earth. The field forms around the Earth’s magnetic poles, which rotate every 10,000 years. Our magnetic poles are shifting right now and will change possibly within your lifetime. The earth’s magnetic field is believed to be caused by the fluid motion of the outer molten core caused by the earth’s rotation acting like a dynamo generating a magnetic field in the axial direction. Solar wind Solar Wind Solar Wind can also interfere with communication devices on Earth, such as cell phones.

Aurora Borealis- (Northern Lights)when charge particles from the sun are attracted to our magnetic poles. ­As the electrons enter the earth's upper atmosphere, they will encounter atoms of oxygen and nitrogen at altitudes from 20 to 200 miles above the earth's surface. The color of the aurora depends on which atom is struck, and the altitude of the meeting: Green - oxygen, up to 150 miles in altitude Red - oxygen, above 150 miles in altitude Blue - nitrogen, up to 60 miles in altitude Purple/violet - nitrogen, above 60 miles in altitude

Solar Flares This is a solar storm explosion on the surface of the sun. Gas and energy is shot from the surface with a temperature of 12,000°C. Solar Flares are much larger than our Earth. Solar Flares can interact with Earth’s atmosphere causing from problems with communication and cell phone use. Example: Air Force One 1984 with President Regan, while in-route to China (during the Cold War!) EARTH Earth

Creation of the moon The impact theory Based on examining rocks of the lunar surface, scientists have determined the age of the moon to be 3.8-4.5 billion years old, same as the Earth. According to the Impact Theory, the Moon formed as the result of a collision between Earth and a Mars-sized object about 4.5 billions years ago. The impacts caused materials from the incoming body and Earth’s outer layers to be ejected into space, where over time they merged to form the moon. The Moon is made up of small amount of iron at the core, and mostly silicate material that came from earth’s mantle and crust. The Moon’s crust is therefore similar to the Earth’s crust. A molten Earth, 4.5 Billion years ago.

Moon facts 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! Moon’s atmosphere is extremely thin weighting only 22,000lbs. Albedo is the percentage of light that is reflected by an object. The moon’s albedo is 7% compared to 31% of Earth. The moon is small with a diameter about the distance from New York to San Francisco. 1.2% the mass of the Earth

Surface of the Moon: Maria 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 Maria(mare)-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). Rays Highlands Crater Rilles craters The moon’s surface has been heavily cratered due to its atmosphere being too thin to protect. (too little gravity)

Dark Side of the Moon Synchronous rotation: the moon’s rotation equals its revolution (both at 29.5 days) Scientists theorize that Earth’s gravity slowed the Moon’s original spin until the moon reached its synchronous rotation. 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 side facing the earth has more maria (mare) because the crust of the moon on this side that faces Earth is thinner. When there was magma under the moon’s crust, the side of the moon facing earth, had more magma pulled to the surface. The dark side is all craters because the crust is too thick to allow ancient magma to come to the surface. The side that faces us 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. The lunar surface also experiences “moonquakes” (around 3000 a year)due to earths gravitational pull.

Phases of the moon 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 is 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, the is called

Phases of the moon

Spring tides 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 a solar eclipse is 2-3 minutes, 7.5 maximum, while a lunar eclipse can last 3-5 hours.

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.

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 big exploration is to search to see if the Moon ever had water. 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.youtube.com/watch?v=tgyNjNKyjb8