Earth, Moon & Sun Astronomy

Movement of the Earth Rotation is the earth spinning on its axis. Earth’s rotation causes day and night (approx. 24 hours). Revolution is the movement of one object around another object. This is the movement of the earth around the sun. Earth’s revolution determines the length of a year(365.25 days).

Seasons on Earth Earth has seasons because its axis is tilted as it moves around the sun. Vernal equinox has equal day and night (March). Summer solstice has the longest day and shortest night (June). Autumnal equinox has equal day and night (September). Winter Solstice has the shortest day and longest night (December).

Seasons continued During equinoxes, the sun is directly over the equator. During the summer solstice, the sun is directly over the Tropic of Cancer. During the winter solstice, the sun is directly over the Tropic of Capricorn.

What causes Earth to experience different seasons? It rotates on its axis while it revolves around the sun. It revolves on its axis while it rotates around the sun. It is tilted while it rotates around the sun. It is tilted while it revolves around the sun. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

During which season is the axis of the Earth pointed towards the sun? Autumn Spring Summer Winter 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

How does the length of day compare to the length of night during the Vernal Equinox? Day is longer than night. Night is longer than day. The day and night are equal in length. The day and night are not equal in length. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Phases of the Moon The phase of the moon occur because of the movement of the moon around the earth and the earth around the sun. Cycle of phases is about a month in length. Phases of the moon include new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, and waning crescent.

Earth’s Moon Temperature range is -176 oC to 100 oC. 3,476 km in diameter. 1609, Galileo Galilei first used a telescope to view the moon. Features on the moon include craters, highlands & maria. Craters round pits on the moon’s surface. Maria are dark, flat areas on the moon.

Other Facts About Our Moon The period of rotation is 27.3 Earth days. The period of revolution is 27.3 Earth days. Because the length of rotation and revolution are the same, we only ever see one side of the moon. The moon only has 1/6 the gravity of Earth. The moon has no atmosphere.

Exploration of the Moon Use Newton’s 3rd Law of Motion for space travel: for every action force, there is an equal and opposite reaction force. Chinese invented rockets in 1000 AD. 1957 the Soviet Union put Sputnik in to space. Yuri Gagarin was the first man in space. Alan Sheppard was the first American in Space. John Glen was the first American to orbit Earth.

Man on the Moon Mercury mission was designed to get man in space(1 person spaceship). Gemini mission was designed to send 2 men at a time to the moon and back. Apollo mission was designed to land man on the moon. Two men went to the surface, one man orbited the moon. Six missions were successful landing on the moon from 1969-72.

Which phase occurs when the moon is in between the Earth and the sun? Full moon New moon 1st Quarter moon 3rd quarter moon 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Solar Eclipses Occurs during a new moon when the moon is between the sun and earth. The shadow is the umbra, the partial shadow is the penumbra. Doesn’t happen every month because the moon’s orbit around the earth is tilted and this prevents the sun, earth and moon from being in a straight line. Do not look at a solar eclipse without protective eye gear.

Lunar Eclipse Occurs during a full moon phase when the earth is between the sun and the moon. More common than the solar eclipse. Can be view without protective eye gear.

When studying a solar eclipse, which is the proper method for viewing the sun? Wear sunglasses Use a refracting telescope Use a pinhole camera Use a magnifying glass 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Tides Tides are caused by the gravitational attraction between the moon and earth. High tides are 12.5 hours apart. Spring tide is the highest high tide and occur at full and new moon phases. Neap tide is the lowest high tide and occur at first and last quarter moon phases.

Space Stations 1971-Salyut 1973-Skylab 1986-Mir 1998-International Space Station

Space Shuttle First space shuttle launched in 1980. Space shuttle design to take astronauts in to the upper Earth’s atmosphere to orbit. Challenger disaster killed seven astronauts in 1986. Columbia disaster killed seven astronauts in 2003. Current Fleet includes Discover, Atlantis and Endeavour.

Refracting Telescope Telescope is made from two convex lenses. First used by Galileo. Limited in size.

Reflecting Telescope Telescope made from a concave mirror and a convex lens. First used by Isaac Newton. Can make a larger telescope than a refracting telescope.

Radio Telescope Has a large dish that collect radio waves. Computers interprets the radio waves. Has detected pulsars, quasars & black holes.

What keeps planets revolving around the sun? The sun’s gravitational pull. The Planet’s mass. The planet’s magnetic field. The Sun’s inertia. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Radio- refracting-reflecting Reflecting – refracting –radio One of the greatest advancements in astronomy was the telescope. Which is the correct order ofadvancements? Radio- refracting-reflecting Reflecting – refracting –radio Refracting-reflecting-radio Radio- reflecting-refracting 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

An icy object that has an elongated orbit around the sun is referred to as a(n)…. Asteroid Comet Meteor Meteorite 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Why does a meteoroid or asteroid create a streak of light when entering the Earth’s atmosphere? Light from the sun is reflected of the surface of each Energy is released from the objects Lightning is produced from these objects Light is a result of friction from the gasses in the atmosphere 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Review Questions What is the spinning on an axis called? (rotation) What do we call a planet’s travel around the sun? (revolution) What is the Egyptian’s calendar based on? What is the Roman’s calendar based on? (cycle of moon phases) What causes the seasons? (tilt of the earth’s axis)

Review Questions What is the first day of spring called? (Vernal Equinox) What is the first day of summer called? (Summer Solstice) What is the first day of autumn called? (Autumnal Equinox) What is the first day of winter called? (Winter Solstice) During the equinox, where is the sun over? (the equator)

Review Questions During the solstice, where is the sun over? (23.5o N or S latitude) How long does it take for the moon to rotate? (27.3 days) How long does it take for the moon to orbit the earth? Why do we only ever see one side of the moon? (length of rotation and revolution are the same) What causes the change in moon phases? (changes in relative positions of the moon, Earth and sun)

Review Questions How long does it take for a full cycle of moon phases? (29.5 days) Name the phases of the moon in order from the least amount of light to the greatest amount of light. (New, Waxing Crescent, First Quarter, Waxing Gibbous, Full, Waning Gibbous, Third Quarter, Waning Crescent, New) What happens when the moon passes between the sun and the Earth, casting a shadow on the Earth? (solar eclipse) What happens when the Earth passes between the sun and the moon casting a shadow on the moon? (lunar eclipse)

Review Questions What is the darkest part of an eclipse called? (umbra) What is the largest part of the shadow of an eclipse called? (penumbra) How long does it take for a another high tide to occur after a high tide? (12.5 hours) What type of tide is caused when the sun, Earth and moon are in a straight line? (Spring Tide) What type of tide is caused when the sun, Earth and moon are at a right angle to each other? (Neap Tide)

Review Questions Which law of physics allows rockets to be launched into space? (Newton’s Third Law of Motion) What type of satellite orbits around Earth at the same rate that the earth rotates? (geosynchronous) Who invented the first rocket? (Chinese) What is used today to transports astronauts and supplies to the Space Station? (space shuttle) How does the gravity on the moon compare to the gravity on earth? (1/6 gravity on moon)

Review Questions How does the diameter of the moon compare to the diameter of the earth? (moon’s diameter is ¼ the diameter of Earth) How does the density of the moon compare to the density of Earth? (the same) Who invented the first telescope? (Galileo) What are the dark flat areas of the moon? (maria) What did Galileo think the maria was? (oceans)

Review Questions In what year did Apollo 11 land on the moon? (1969) What are the lighter mountainous areas on the moon called? (highlands) What are the circular impressions on the moon called? (craters) What causes the formation of the craters? (meteor impacts) How long does it take the Earth to rotate? (24 hours)

Review Questions How long does it take the Earth to revolve around the sun? (365.25 days) What is the path of the earth around the sun called? (orbit) Why is there not a lunar eclipse during every full moon and a solar eclipse during every new moon? (Earth, moon and sun must be in a straight line) How was the moon formed? (A large object struck the earth and torn a portion of the earth away to form the moon.) What causes the tides? (moon’s gravity)