Download Origin of Our Solar System 2 Theories Sun formed first then planets

Origin of Our Solar System
2 Theories
Sun formed first then planets
Formed at the same time (nebula theory)
Giant nebula was the source of material for solar system
Nearby “shock” of a supernova caused some of the material to condense (like the
birth of a star)
Around 4-5 billion years ago
How do you make a Planet?
While the sun was forming, material in the nebula began colliding, making bigger and bigger
pieces
These small bodies of matter is called planetoids (think of them as seeds)
As collision continues, these bodies get bigger and form protoplanets
These bodies now have some gravity
Pull materials toward them and make protoplanets bigger or capture moons
The Planets
8 true planets and several dwarfs (including Pluto)
Larger objects that orbit the central star
Kepler offered three laws to explain the movement of planets around the sun
Law of ellipses
Each path of a planet is an ellipse
Perihelion and aphelion
Distance is the average of the two
Law of Equal Areas
Planets travel at different speeds in their orbits
Faster closer to the sun
Slower away from the sun
Law of Periods
Relation between the distance of the planet from the sun and how long it takes to
make 1 rotation
Closer planets take less time to make 1 rotation
Further planets take more time to make 1 rotation
Sir Issac Newton sealed the deal with inertia
An object will move in a straight line at constant speed until acted upon by an
outside force
gravity
The Sun’s Influence
Once the sun gets big enough it influences how the planets forms
Gravity pulls protoplanets into an orbit
Heat from the sun boils off lighter gases like hydrogen, helium, ammonia, and methane
from close planets
Gravity also pulls heavier elements like iron to closer planets
Other planets further away stay cold and freeze
Solar System Layout
Our solar system can be divide into two parts
Inner planets and outer planets
4 closest planets to the sun
Mercury, Venus, Earth, Mars
Solid rock with metal core
Few moons (0-2)
Impact craters
Heat from sun boiled off lighter gasses so thinner atmospheres
Hydrogen, helium, methane, ammonia
Gas giants or Jovian planets
Jupiter, Saturn, Uranus, Neptune
Very large and massive
Very dense atmospheres
Mostly lighter gases like hydrogen and helium
Many moons
Pluto is dwarf planet
Mercury
No good image since its so close to the sun
Large temperature fluctuations
427°C to -173°C
No moons
Heavily crated surface
Thin atmosphere
Venus
Opposite rotation than the rest of the planets
No moons
Very similar to Earth in mass, size, and density
Much hotter (ave. temp is 453°C)
Atmosphere is much more dense (100 times Earth)
Carbon dioxide is 92% of atmosphere
Lets orange wavelength through
Blocks heat from escaping
Clouds are sulfuric acid droplets
Rocky landscape with remnant volcanoes
Earth
Only planet with liquid water
Only planet with life
Mars
Has a tilt like Earth-seasons
2 moons
Geologically active in past
Volcanoes and canyons
Evidence of water erosion
Jupiter
Largest planet in size and mass
At least 16 moons
Internal temperature reaches 30,000°C
No solid surface
92% hydrogen and helium
Layered look of gases
Due to spin of the planet
Colors due to trace gases like methane and ammonia
Great Red Spot
Giant storm
Winds up to 600 km/hr
Saturn
Next largest planet
Average temp of -176°C
At least 20 moons
Numerous rings of material
Color bands like Jupiter but less pronounced
Uranus
3rd largest
Has smaller band of rings
Discovered in 1781
Unusual rotation, 180°, rolls like a ball
Green color indicates methane in atmosphere
Neptune
8 moons and 4 rings
Predicted before it was discovered
Frozen clouds of methane
Great Dark spot
Another storm
>1000 km/he
Very active weather systems
Average temp of -225°C
Pluto
Now a dwarf planet
More of a terrestrial planet, not a gas giant
It’s moon Charon moved Pluto from a planet to a dwarf planet; its not small enough
Also known as the Double Planet