Telescope-17th century-Galileo
Solar system- sun and the objects that orbit it such as planets, moons, and etc.; solar
system within a solar system (Saturn and its moons)
Measuring distance in space:
1-astronomical unit (AU) - average distance between the Earth and the sun; approx
2-speed of light-approx 300,000 km/second in space
3-light minute-light travels 18,000,000 km/minute
Sunlight reaches Earth in 8.3 minutes
Clue: My very excellent mom just served us nachos
Planets (order): mercury Venus Earth mars Jupiter Saturn Uranus Neptune
All planets rotate and revolve...
A. Rotate-spinning on an axis...day
Prograde-rotate counterclockwise-Earth...sun rises in E and sets in W
Retrograde-rotate clockwise-Venus
B. Revolve-orbit AROUND another object...year
Two types of planets:
1-Inner planets: closet to sun: Mercury, Venus, Earth and Mars aka Terrestrial
Characteristics: 1-spaced close together 2-small 3-rocky and dense
2-Outer planets: farther from sun: Jupiter, Saturn, Uranus, And Neptune
aka Gas Giants
Characteristics: 1- spaced FAR apart 2- large 3-made of mostly gas
SUN
...is a star (radiates)
...99.8% of SS total mass
Diameter: 1,391,000 km
...made of (H), (70%)-Hydrogen, (He), (28%)- Helium
...temp varies from 6,000°C on the surface to 16,000,000°C at the core...16.6Kelvin
...rotates approx every 30 days
Landscape:
1- sunspots-darker, cooler parts of the sun (11 year cyle)
2-solar flares-explosions of hot gases on the sun's surface
Ways solar flares can affect Earth: 1-power line surges
2-radio wave interference
3-creating an aurora borealis
3- Solar prominences-are has of hot gases seen on the sun's surface
...is about 4.5 billion years old-1/2 life- 4.5 billion years left
...when the sun dies; it will turn into a red giant: grows larger and larger
Until it explodes blowing out its outer layer
150,000,000 km
Parts of sun:
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Photosphere -- The innermost part of the sun's atmosphere and
the only part we can see.
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Chromosphere -- The area between the photosphere and the
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corona; hotter than the photosphere.
Corona -- The extremely hot outermost layer, extending outward
several million miles from the chromosphere…halo
Core -- The center of the sun, comprising 25 percent of its radius
Inner Planets aka Terrestrial Planets
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Closet to the sun
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are dense and rocky
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Spaced Close together
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Mercury, Venus, Earth and Mars
Mercury
...closest planet to sun
...Diameter- 4,879 km
...Distance from sun- 0.38 AU
…second most dense planet
...smallest planet in OUR SS and because of its size has
low gravity...also it is nearly absent of atmosphere
...a day on Mercury equals 59 Earth days ...Mercurian year equals 88
Earth days...so, Mercurian year is 1.5 Mercurian days
...temperature is 90°K to 700K...430°C (day) and -180°C (night)
...surface is heavily cratered, similar to Earth's moon
...Mercury has no known natural satellites
Venus
...Diameter- 12,104km
...Distance from sun- 0.72AU
...atmospheric pressure is 90x Earth's atmosphere...would crush a human
...atmosphere is made of carbon dioxide and sulfuric acid… causes heat to be trapped
...HOTTEST planet because the clouds trap solar energy making it H.O.T.!!!!
...Venus atmosphere have a Greenhouse Effect gone wild!!!
...temp 464°C...hot enough to melt lead and other metals
...has a retrograde rotation…clockwise…right…sun rises in the West
...said to be Earth's twin
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similar size
 composition: crust of iron and mantle of rock
...has no known natural satellite
Earth
Distance from sun: 92 million km
Diameter of Earth: 12,756 km
...3rd planet from sun (Third Rock from the Sun)
...nickname: Blue Planet
...71% of Earth is covered by water
...5th largest planet
...MOST dense planet
...Earth has 1 natural satellite
..Thick atmosphere of nitrogen, carbon dioxide and oxygen
..Temps vary from +60C to -90°C
...rotates: 24 hours...1day...revolves: 365 1\4 days...1calendar year
...every 4 years...add 4 1/4days to get 1 day...add to calendar...Leap Year
...prograde rotation-spins counterclockwise…Left…sun rises in the East
...Special because:
-only planet known to have LIQUID water on its surface
-only planet known to support life (as we know it)
-only planet to have water in 3 forms: s, l &g
...Ozone layer-protects Earth from UV rays
Characteristics of Earth:
Crust-surface
MantleCore:
Inner-solid
Outer-liquid
Mars
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Distance from sun- 1.52 AU
Diameter 6,794 km
Mars is the 4th planet from the sun
Referred to as the Red Planet b/c its surface contains iron oxide aka rust.
Evidence of erosion on Mars from floods and river systems:
erosion & sediment
Mars is similar to Earth, but is much colder
Mars has 2 natural satellites: Phobos and Deimos
Has seasons and polar ice caps…indicate that Mars ONCE had LIQUID water
Outer planets: aka Gas Giants
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farther from sun
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spaced farther apart from each other
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Jupiter, Saturn, Uranus, And Neptune
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large
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made of mostly gas
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thick atmospheres
Jupiter
• distance from sun-5.20 AU
• diameter- 142,984 km
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Saturn
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Jupiter is the 5th planet from the sun
Largest planet in our solar system
It is 90% hydrogen and 10% helium
Its atmosphere: hydrogen, ammonia, methane and helium
Storms: Great Red Spot…400 years
Produces MORE heat than the sun
VERY HOT, Hydrogen turns to liquid
Jupiter has 63 natural satellites…Lo is Jupiter’s ACTIVE volcano
Shortest days (less than 10 hrs)…it spins faster than Earth does
Very thin ring around it
Distance from sun 9.54 AU
Diameter- 120,536 km
6th planet from the sun and is the 2nd largest
75% hydrogen and 25% helium
4 rings: two can be seen from Earth
two can’t be seen from Earth
rings are composed of dust and water ice
are found above its equator
produces more heat than the sun
Saturn has 34 natural satellites; its largest being Titan.
Titan has an atmosphere much like primitive Earth.
Is still forming
Uranus
• Distance 19.22 AU
• Diameter 51,118 km
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7th planet from the sun
Need to a telescope to view from Earth
Is tilted at a right angle (parallel) so poles towards the sun
Planet is composed of mostly rock and various ices.
Atmosphere mainly hydrogen (H) helium (He) and methane (blue-green)
Has blue-green tint to it because it absorbs red light.
Uranus has 27 natural satellites
Neptune
• Distance 30.06A
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Diameter 49,528 km
8th planet from the sun, 4th largest
Sometimes, Pluto’s orbit crosses Neptune’s orbit, temporarily making Neptune the furthest planet fro
m the sun.
Planet is composed of rock and ice, methane (blue-green tint)
Atmosphere composed of H, He and methane (Bluish green color)
Has clouds and weather
Great Dark Spot (storm the size of earth)
is half the size of Jupiter’s Red Spot
disappeared 1994…did return
Last of gas giants with rings around it
Has 25 natural satellites; Largest satellite, Triton, has geysers that shoot Nitrogen into space
Triton still has indications of lava flowing on its surface