Transcript Solar System - ppt

Solar System
Inner planets
Outer planets
Solar Nebular Theory
How did the solar system begin?
The solar system began as a huge cloud of dust and gas
called a ________________.
Nebula
Gravity
_________________
caused the cloud to condense
and form the sun and its nine planets.
Hydrogen
Helium
Primary gases were ______________
and ______________.
5
The solar system began to form about ____
billion years ago
when a star exploded in a huge supernova. Particles form its
explosion “rained down” on a nearby nebula, “seeding” it with
The sun
planets
chemicals that would become ___________
and its __________.
The nebula had been slowly rotating, but began to collapse to
its center. The nebula’s rotational speed increased which
flattened the nebula into a more disk-like shape.
As the cloud continued to collapse in on itself, a large massive
protosun
___________
formed in the center.
Smaller clumps of matter formed around the central protosun
planets
forming the _____________.
_____
Inner ________were
planets
so close to the sun’s heat that the lighter
elements like H and He boiled away. All that was left were the
Terrestrial
heavier, rocky, metallic elements. They are called _________
Planets.
Mercury Venus, Earth and ________.
Mars
They include __________,
The ______
outer planets farther from the sun were not so affected
by the sun’s heat. They retained their lighter gases and grew to
enormous sizes. These were called the Gas Giants or ______
Jovian
planets.
They are Jupiter, _________,
Saturn Uranus, and _________.
Neptune
Smaller clumps of matter formed around the planets. These
satellites or moons.
became ____________
_________
Pluto
is believed to be an escaped moon of Neptune.
__________
Asteroids exist between Mars and Jupiter.
Mercury
• Closest planet to the Sun
• Shortest period of revolution
• During day, planet is hot, but at night,
it is freezing cold.
• Almost no atmosphere (no weather)
• no moons or rings
• First explored by Mariner 10 in 1975
• Lots of impact craters (like our moon)
Venus
• Earth’s twin because it’s similar in
diameter, mass, size
• Atmosphere is mostly carbon dioxide and
about 3% nitrogen. The yellow clouds are
concentrated sulfuric acid
•thick clouds cause this to be the hottest
planet because of the Greenhouse Effect
• Has phases like our moon
•First radar mapped by Magellan in 1991
• Brightest planet
Mars
• Called the Red Planet
•1 Martian year = about 2 Earth years
• Atmosphere – 95% Carbon Dioxide
and 5% Nitrogen.
Very thin with clouds of ice
• appears to have season – polar ice caps
• Has 2 moons – Phoebus and Deimos
• Explored by Mariner 4 (1965), Viking (1976), Pathfinder (1997)
and Rovers – Spirit and Opportunity (2004)
• evidence of liquid water on its surface
• has largest known mountain in the solar system (Olympus Mons)
Jupiter
• Largest planet
• Rotates once every 10 hours
• Atmosphere – 90% Hydrogen, 10% Helium,
methane, and ammonia
• Great Red Spot – possibly a calm area in a very turbulent atmosphere
(high winds from internal heat). Radiates more energy than it receives
from sun
• Has 63 moons (as of February 2004) - 4 largest visible with
binoculars – Io, Europa, Ganymede, Callisto
Io – most geologically active volcano
• Has faint rings (dark colored)
• Visited by Pioneer 10 (1973) & 11 and Voyagers I & II in late 70s
• Liquid metallic Hydrogen (high pressure)
Saturn
• Second largest planet
• Atmosphere – 75% Hydrogen, 25%
Helium
• Has colored bands of gases (like Jupiter)
• Has 34 moons – Titan is well known
•Has 7 rings and 1000s of ringlets
• Visited by Pioneer 11 (1979), Voyager I & II, and
Cassini in 2004
• Such a low density, could float on water
Uranus
• Rotation 17.2 hours (slowest of Jovians)
1 Uraniun year – 84 Earth years
•Atmosphere is 83% Hydrogen, 15% Helium, and
2% methane. Planet appears blue because the red
is absorbed by the methane in the atmosphere
•Has 21 named moons and 6 unnamed; only moons named after
Shakespeare and Pope
• 11 rings
• Visited by Voyager 2 (1986)
• Rotates almost on its side with South Pole facing the Sun
Neptune
• Smallest gas planet
• 1 Neptunian year = 16.5 Earth years
• Atmosphere is 15% Hydrogen, little Helium,
and methane (blue appearance)
• Great Dark Spot; fastest winds in solar
system 2000 km/hour
• Gives off 2.7 times more energy than it receives from the Sun
•Has 13 known moons and 4 rings
Triton is Neptune’s largest moon and the coldest known place
in solar system
• Discovered in 1846
• Visited by Voyager 2 (1989)
PLUTO
• NOT a Jovian planet, but it is an outer planet
• 1 Plutonian year – 248 Earth Years
• Discovered in 1930
• Atmosphere is mostly frozen methane and helium
•Has 1 moon – Charon
• Has not been visited yet, but
• Its orbit is so elliptical that it was actually nearer to
the Sun than Neptune until March 1999.