Earth, Moon, & Sun System

Earth(Physical Characteristic)

• Approximately 149,597,890 km (92,955,820 miles) or 1 AU from the Sun

• Diameter at the equator is 12,756 km (7,926 miles), and its circumference is 40,075 km (24,901 miles)

• Mass is 5.9737 x 1024 kg (6.58 x 1021 tons) • Gravity is 9.8 m/s2 • Density is 5.515 g/cm3

• The average temperature is 14oC (57oF) and ranges from -89oC – 58oC (-128oF 136oF)

• Atmosphere consists of 78% Nitrogen (N2), 21% Oxygen (O2) and 1% of other gases such as Carbon Dioxide (CO2)

• Orbits the Sun in 365.24 Earth days• Rotates in 24 hours• Tilted 23° on its axis reason for the seasons• Has three layers - crust, mantle, and core

Earth(Special Features)

• Ideally situated away from the sun life can exist• Has oceans that help maintain a stable

temperature• Has a molten iron core that generates a magnetic

field around the planet helps protect the planet from the harmful effects of solar winds and cosmic rays

• Has oxygen which is essential for life• Has an ozone layer (composed of O3) that resides

in the stratosphere absorbs harmful UV light

WinterDecember

Solstice

SpringMarch Equinox

SummerJune Solstice

Fall September Equinox

Earth(Seasons)

• Patterns of temperature changes and other weather trends over the course of a year are known as seasons

• Results from Earth’s 23° tilt on its axis and its orbit relative to the Sun – Equinox – sunlight shines equally on the northern and southern

hemispheres– Solstice – sunlight is at its maximum in one hemisphere and a

minimum in the other hemisphere

153,000,000 km148,000,000 km

October

November

January

February

April

May

July

August

Which hemispherewould have

theseparticular seasons?

Not to scale

Moon(Physical Characteristic)

• Approximately 384,400 km (239,000 miles) from the Earth• Diameter is 3479 kilometers (2162 miles), which is about

1/4 the diameter of the Earth• Mass is 7.35 x 1022 kilograms (8.1 x 1019 tons), which is

about 1/80 the mass of the Earth. • Gravity is 1.6 m/s2, which is about 1/6 the gravity of Earth• Density is 3.340 g/cm3 • Does not have an atmosphere• The average temperature on the surface of the Moon during

the day is 107°C and during the night, the average temperature drops to −153°C

• Orbits the Earth in 27.3 Earth days• Rotates in 27.3 Earth days• Tilted 70 on its “axis”• Orbit is tilted 50 • Has three layers - crust, mantle, and core

Image taken from: http://www.thelivingmoon.com/43ancients/02files/Moon_Images.html

Moon(Special Features)

• Has impact craters that are the result of small objects from space striking the Moon’s surface

• Has mare (maria - pl.) which are large, dark plains of solidified lava

• The same side of the Moon always faces the Earth; this is because of tidal locking

• Is thought to have formed after a giant collision between early Earth and a smaller space body

• Is moving away from the Earth at a rate of 3.8 cm/year

Moon(Phases)

• The lunar phases result from the positions of the Earth, Moon, and Sun. – Waxing – the phase after the new moon when the amount of reflected

light increases– Waning – the phase when the full moon has passed and the amount of

reflected light decreases What we see

New Moon

Moon viewer

Waxing CrescentWaxing GibbousFull Moon1st QuarterWaning GibbousThird QuarterWaning CrescentNew Moon (Again)

Moon(Eclipses)

• An eclipse occurs when the Earth, Moon, and Sun are in line with each other and a shadow makes the Sun or Moon seem to grow dark. – Lunar eclipse – the phase after the new moon when the amount of

reflected light increases– Solar eclipse – the phase when the full moon has passed and the

amount of reflected light decreasesWhat we see

New Moon

Moon viewer

Moon(Tides)

• Tides occur because the Moon’s gravity changes the shape of Earth’s oceans– Lunar eclipse – the phase after the new moon

when the amount of reflected light increases

What do you think happens to the tides when

the Sun and Moon are on

directly in line with Earth?

Sun(Physical Characteristic)

• Approximately 149,600,000 km (92 million miles) from the Earth• Approximately 1,390,000 km in diameter which is over 100 times

the diameter of the Earth • Mass is about 2 x 1030 kilograms, which is is over 300,000 times

the mass of Earth• Has an atmosphere • Consists of about 70% Hydrogen, 28% Helium and 2% of metals

such as iron. • The surface at the equator rotates once every 25.4 Earth days.

The rotation near the poles is around 36 Earth days. Also the surface swirls in high and low pressure areas, similar to those that occur on Earth.

• Its temperature is extremely hot, with the surface being about 5000°C (9032oF) and the center core at about 15,600,000° C (28,080,032oF)

• Has three layers - core, radiative zone, and convection zone

• Rotates every 25.38 Earth days

Image taken from: http://science.nasa.gov/headlines/y2003/23oct_superstorm.htm

Sun(Features)

• continually emits a stream of charged particles consisting mostly of electrons and protons called solar winds

• shoots out streams of high energy particles called solar flares aurora borealis

• Contains sunspots which are spots on the photosphere that are cooler than surrounding areas

• Prominences are huge loops of glowing gas that extend into the corona

• Atmosphere photosphere, chromosphere, and corona