Mr. Vallee’s Planets
Student Handout
http://brainpop.com
http://solarsystem.nasa.gov/planets/index.cfm
http://www.nationalgeographic.com/solarsystem/ax/high.html
http://nineplanets.org/
I.
Planets - General Information and Characteristics
A. General Information. Planets circle the Sun in elliptical orbits.
1. Sequence from closest to furthest from Sun: Mercury,
Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
2. Perihelion – orbit when the planet is closest to the sun
3. Aphelion – Orbit when planet is furthest away from sun
4. Mercury has most elliptical orbit
5. Other planets/satellites orbit almost circular
6. Planets in same plane as Sun, except Mercury
7. Rotate on axis (ancient collisions)
8. Venus rotates opposite direction / Uranus on its side.
B. Inner Planets: most dense of planets, crust (surface layer),
mantle (inner solid layers), and a core (dense & rich in iron)
1. Mercury
http://www.nasm.si.edu/ceps/etp/mercury/
a.
b.
c.
d.
e.
f.
g.
h.
i.
(SITE IS GOOD FOR ALL PLANETS)
innermost planet
most elliptical
axis tilt 0 degrees
surface totally pockmarked (craters)
sunrise – minus 183 degrees C, early evening 427
degrees C (Earth doesn’t get that cold)
iron core generates a magnetic field (2 times as rich
as any other, makes gravity 1/3 that of Earth, despite
mass of 1/18
fastest planet
atmosphere is so thin, it is barely detectable
exploration-70’s Mariner 10 sent back photos,
providing information about it
2. Venus
a. comparable to Earth in size, mass, density
b. early volcanic action helped shape surface / still has
huge volcanoes and mountain ranges
c. dense CO2 atmosphere – allows some solar energy to
pass through the clouds and then heat the surface,
BUT prevents heat from escaping back into space
(greenhouse effect)
d. upper clouds poisonous sulfuric acid
e. no moon
f. Venus day = 243 Earth days
g. orbit closest to a perfect circle
h. rotates clockwise on axis, sun rises in west, sets in
east
i. exploration – Oct 83 Soviets, Sep 90 Magellan, Dec
78 Pioneer Venus (2)
3. Earth – Only planet that can sustain life as we know it
4. Mars – known as the “Red Planet”.
a. ½ size of Earth
b. thin atmosphere, largely CO2, along with water vapor
c. freezes at poles – has polar ice caps (dry ice)
volcanic activity
d. craters, giant canyons (why?)
e. 2 miniature moons are probably captured asteroids
f. Mars day = 24 hours, 37 minutes
g. axis tilt 25.2 degrees (similar to Earth’s)
h. for many years, some thought it had life
i. largest mountain/volcano in Solar System– Olympus
Mons
j. has seasons (tell by ice cap size)
k. exploration is ongoing
C. Outer Planets
1. Jupiter – Gas Giant, King of the Planets
a. Mostly composed of hydrogen and helium
b. Outer layer of planet is gaseous
c. Inner layer of planet has liquid hydrogen
d. Core is dense/rocky and equals 10-30 times Earth’s
mass
e. Equator bulges from centrifugal force due to rapid
rotation
f. Great Red Spot – giant storm w/winds 360 km/hr, 2-3
times the size of the Earth, and has light/dark clouds.
g. Shortest rotation, spins once every 9 hrs, 50 minutes;
causes equatorial regions to bulge.
h. At least 64 moons (4 as big as small planets)
i. Has 2 asteroid groups (Trojans) in Jupiter’s orbit
j. Faint ring system – particles from Io moon (most
volcanically active in solar system) and surface causes
electrical cloud to form rings
k. Powerful magnetic field
l. Emits more energy than receives from Sun (Sun that
failed??)
2. Saturn – Gas Giant/Planet with ears
a. When Galileo studied it in 1610, he saw rings as two
knob-like shapes, called them ears
b. Magnificent ring system (7 rings / A-G); has billions
of small rock/ice particles
c. Has at least 62 moons
d. Rapid rotation – bulge in center, flat-like on bottom
and top poles
e. 2nd largest planet
f. Not as stormy as Jupiter
g. Made mainly from hydrogen and helium
h. Radiates more heat than it receives from the sun (like
Jupiter) / has a rocky core
3. Uranus – A world on its side
a. First planet to be discovered using a telescope
b. Rotates on its side (causes each pole to spend 42 years
in direct sunlight and then 42 years in darkness)
c. Hydrogen-rich atmosphere
d. Great # of ice patches (water ice & ammonia)
e. Bluish-green color (clouds)
f. Has 11 coal colored rings, ring materials are larger &
more sparse (discovery of rings by Voyager)
g. Has at least 27 moons
h. 3rd largest planet
i. planet made of light gases and ice
4. Neptune – Last of the Giants
a. Has at least 13 moons
b. smallest and last of Gas Giants
c. Hard to study due to distance from Earth
d. Cannot see w/out a telescope
e. Like Jupiter/Saturn, internal heat drives Neptune’s
turbulence
f. Rings are narrow, faint, dark (4 of them), can’t
explain why
g. Blue-green color planet; blue color comes from the
scattering of sunlight / bright ammonia-ice clouds
h. Great Dark Spot – circular storm, the size of Earth /
White spot “Scooter” rapid motion
i. Radiates more than twice the solar energy than it
receives from the sun
II.
Dwarf Planets
A. General information and characteristics: A dwarf planet is
something that looks like a planet, but is not a planet. The
dwarf planets are bodies in the solar system, which are large
enough to become round due to their own gravitational
attraction. Unlike planets, dwarf planets lack the gravitational
muscle to sweep up or scatter objects near their orbits. They end
up orbiting the Sun in zones of similar objects such as the
asteroid and Kuiper belts. The actual definition of "dwarf
planet" is kind of technical - a celestial body that: is in orbit
around the sun, has sufficient mass for its self-gravity to
overcome rigid body forces so that it assumes a hydrostatic
equilibrium (nearly round) shape, has not cleared the
neighborhood around its orbit, and is not a satellite.
1. Pluto – A ball of rock and water ice, topped with methane
ice. Has 5 moons: Charon, Hydra, Nix, Kerberos and Styx.
a. Charon is largest moon in solar system in relation to
the size of its dwarf planet/planet
b. There is debate whether Pluto and Charon are escaped
moons of Neptune
c. Most elliptical orbit of planets/dwarf planets (4.4 b.
KM / 7.4 b. KM)
d. From 1979 – 1999, Pluto was closer to the sun than
Neptune
e. Takes 248 Earth years to orbit the sun
f. Orbits on its side (like Uranus)
2. Ceres – is the largest object in the asteroid belt between
Mars and Jupiter. Hailed as a new planet when it was
discovered in 1801, the rock and ice orb was demoted when
other asteroids were found. Diameter is 602 miles.
3. Eris – Might be the largest known body in the Kuiper Belt.
Brighter than Pluto, and maybe slightly bigger (?). Eris seems
to be rock and water ice with a methane ice covering.
a. Orbits sun on the same plane as Earth/most other
planets
b. Takes about 560 years to orbit the Sun.
c. It is now at its furthest point/distance from the sun – 9
billion miles.
d. It will reach its closest point to the sun – about 3
billion miles (about Neptune’s distance from the sun) in
280 years.
e. It is nearly 1,491 miles in diameter (smaller than our
moon).
f. Cold and desolate place – If a person was standing on
the surface of Eris and held a pin up to the sun, the head
of the pin would cover the sun.
g. Temperatures on its surface probably range from about
minus 400 to minus 370 degrees Fahrenheit.
h. Has at least1 moon.
4. Makemake – it is a large icy world that orbits the sun on the
far fringes of the solar system. It is very very cold. The
temperature is about minus 240 degrees C. It is probably
covered in ice that is made of methane and maybe ethane. The
surface is very bright and looks a bit red in color.
a. It takes nearly 310 years to completely orbit the sun.
b. It is usually a bit further from the sun than Pluto.
c. It is smaller than Pluto and Eris, but larger than Ceres.
d. Its diameter is between 1300 and 1900 km (about ¾
the size of Pluto).
5. Haumea – It is a bizarre object that is shaped like a plump
cigar. Its diameter is approximately the same as Pluto’s,
however; its odd shape means that it is much thinner.
a. It is known to be spinning very fast, making one
rotation in about 4 hours.
b. The quick spinning motion is perhaps what gives the
dwarf planet its shape.
c. The dwarf planet is composed of rock with a crust of
pure ice.
d. It has at least two moons.
e. It takes 285 years to orbit the sun.