Science CH 25-26

Earth was spinning so quickly that a chunk spun off and fell into Earth's orbit

Formed simultaneously

Formed elsewhere and got caught in Earth's orbit

A planet-sized object hit Earth, formed a ring, and then the things in the ring combined and fell into Earth's orbit

a celestial body (as small as a speck as large as large...)

depressions from the impact of a meteor/ite

no larger than sand grains

allowed by lack of an atmosphere

major cause of erosion on the moon

(59% because of wobble)

on axis same period as 1 orbit around Earth

• Diameter = 3476 km
• 1/4 Earth's

• Density = 3.3 g/cc
• Earth is 5.5 g/cc

Mass = 1/18 Earth's

• Iron core
• Partially molten region
• Rigid Lithosphere (1,000 km thick)
• Near side crust (65 km thick) Far side crust (150 km thick)

• means "seas" in Latin
• thought basins were filled with water

light areas

rugged mountains pockmarked with craters

great basins and level plains formed when lava spewed up to the surface through factured caused by earlier giant impacts

• fine-grained crystalline rocks
• younger lunar rocks
• 3.1-3.8 billion years old

• higher areas of gravity
• short for "mass concentrations"

• Trenchlick valleys running in Maria Bedrock
• Hadley Rille in Mare Imbrium

rocks made of angular fragments cemented together with fine material

• Earth- formed by volcanic eruptions
• Moon- formed by meteoroids impacts that melted rocks together

• come out of craters
• consist of shattered rocks and dust from the impact

• loose rock material
• grayoish brown mixture of fine particles and small rocks

• Rises in the east, sets in the west
• 27 1/3 days to orbit
• Rises above the horizon at a different time each day
• the moon moves 13. eastward along it's orbit so Earth must rotate 13. each day
• Moon rises and sets about 50 minutes later each day

the moon closest to Earth

the moon when it is farthest from Earth

• 1. New Moon
• 2. Waxing Crescent
• 3. First Quarter
• 4. Waxing Gibbous
• 5. Full Moon
• 6. Waning Gibbous
• 7. Last Quarter
• 8. Waning Crescent

looks bigger

looks smaller

area of total shadow

are of a partial shadow surronding the umbra

• The moon is fully within Earth's umbra
• 1 per year

Sun Earth Moon

• New Moon Phase
• 1 per year
• The moon's umbra reaches Earth
• Perigee

Sun Moon Earth

• The moon's umbra goes just above the Earth
• The moon's penumbra skims the top of the Earth
• Perigee

Sun Moon Earth

• The moon's umbra does not reach the Earth, but it's penumbra does
• Apogee

Sun Moon Earth

nuclei combining of lighter elements to form a heavier element

Hydrogen & Helium

4th State of Matter

• Charged particles (nuclie or ions) with a positive electric charge and electrons, which have a negative charge
• They usually repel each other, but due to their speed, they fuse

Hydrogen & Helium

• Core 15.6 mil
• Radiative Zone 8 mil
• Convection Zone 1.5-2 mil
• Photosphere 6,000
• Chromosphere 20,000
• Corona 1 mil

Hydrogen and Helium ions in a plasma state

• Radiative-
• plasma, but cooler than the core

• Convection-
• rising and falling currents of plasma
• carry energy to the Sun's surface where it is radiated out into space as sunlight

visible surface of the sun

• Granules-
• formed by tops of the currents
• lasts about 20 min

inner layer of the sun's atmosphere

• from one sunspot to another
• like an arch

• thin outer atmosphere
• a million times less bright than the photosphere

• 1 AU
• 150 million km
• 93 million mi

• dark spots on the photosphere
• sunspot cycle- peak every 11 years
• proved that the sun does rotate?

• constant stream of electrically charged particles given off by the corona
• deflected by Earth's magnetic field

solar wind comes out of coronal holes

outbursts of light

• the particles of solar wind interacting with Earth's atmosphere
• only show in the north and south poles because the magnetic field goes in there

the Earth is the center of the universe

when Earth catches up to another planet and goes past it, so it appears that the other planet is going backwards

• puzzled by retrograde motion
• epicycles- circular orbits
• deferent- larger circular orbit

sun is the center of our solar system

• 1. Elliptical (not completely round) orbits
• 2. Equal Area Law
• -the closer to the sun, the faster it's orbit
• 3. Harmonic Law
• -P2=D3

every mass exerts a force of attraction on every other mass, and the strength of that force is proportional to the masses and inversely proportional to the disrance between them

Isaac Newton