Transcript Our solar system - astronomyuniverse

Our Solar System
A sleeping puppy production
Questions/Understandings
What happened after the Big
Bang that formed everything in our solar
system?
• ???:
There are both large and
small celestial bodies in our solar system
including the sun, planets, moons,
asteroids, comets and meteoroids.
• Understanding:
A theory of the beginning….
Scientists believe that the solar system was formed
approximately 4.6 billion years ago when a cloud of gas
and dust (nebula) in space was disturbed, by the
explosion of a nearby star (called a supernova). This
explosion made waves in space which squeezed the cloud
of gas and dust.
Squeezing made the cloud start to collapse, as gravity
pulled the gas and dust together, forming a solar nebula.
Just like a dancer that spins
faster as she pulls in her
arms, the cloud began to
spin as it collapsed.
Eventually, the cloud
grew hotter and denser in
the center, with a disk of
gas and dust surrounding
it that was hot in the
center but cool at the
edges.
Solar Nebula
As the disk got thinner and thinner, particles
began to stick together and form clumps.
Some clumps got bigger, as particles and
small clumps stuck to them, forming planets
and moons.
At the center of the cloud, where planets like
Earth formed, only rocky material could
stand the great heat. Icy matter settled in the
outer region of the disk along with rocky
material, where the giant planets like Jupiter
formed. As the cloud fell in, the center got so
hot that it became a star, the Sun, and blew
most of the gas and dust of the new solar
system with a strong stellar wind.
By studying meteorites, which are thought to be
left over from this early phase of the solar
system, scientists have found that the solar
system is about 4.6 billion years old!
A little about our Solar System
• As you know, planets are
part of our solar system.
Comets, asteroids,
meteoroids, and the
moons are part of the
solar system, too. They
all orbit around a star we
call the sun.
• It's all held together by
gravity.
• The planets are divided
into two groups:
• the four Inner planets
Mercury, Venus, Earth
and Mars
• the four Outer planets
Jupiter, Saturn, Uranus,
Neptune
Tiny Rocky Bodies
• Meteoroid: tiny rocky body in our solar system
• Meteor: a meteoroid that enters Earth’s
atmosphere and burns up. Meteor shower, also
known as a shooting star.
• Meteorite: part of a meteoroid that survives the
trip through Earth’s atmosphere and ends up on
the surface of the earth.
MERCURY
• The diameter of Mercury
is 3,031 miles.
• It takes the planet 58.6
days to rotate completely
360 degrees.
• It takes 88 Earth days for
Mercury to orbit the sun.
• Mercury only weighs
5.5% of what earth
weighs.
• Mercury’s diameter is
38% of what the earth’s
diameter is.
More about Mercury
Mercury is the closest
planet to the sun.
Because Mercury is so
close to the sun (and the
sun's glare) it is difficult to
spot from Earth.
Mercury's gravity is less than
half what we have on Earth, so
Mercury would not be able to
hold onto an atmosphere even
if the sun had not blown its
away.
Since there's no atmosphere
(which on Earth acts like a
warm blanket) temperatures on
Mercury go crazy. It can be a
scorching 750 degrees
Fahrenheit during the day, and
minus 320 at night!
VENUS
• The Diameter of Venus is
7,521 miles.
• It takes 243 days to rotate
360 degrees completely.
• It Takes 225 Earth days
to orbit the sun.
• It only has 82 % of the
mass earth has
• Its diameter is about 95%
of earths.
• It is a 30 percent closer to
the sun that the earth.
More fun facts about Venus
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The second planet from the sun
bakes under twice as much solar
radiation as Earth. Venus reaches
temperatures of 895 degrees
Fahrenheit!
The thick clouds around Venus
rotate much faster than the planet
itself -- once every four days. Not
counting the moon, Venus is the
brightest object in the night sky.
The CO2 atmosphere of Venus is
very hot and thick. You would not
survive a visit to the surface of the
planet - you couldn't breathe the
air, you would be crushed by the
enormous weight of the
atmosphere, and you would burn
up in surface temperatures high
enough to melt lead.
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The surface of Venus is mostly a
rocky desert (there are many
computer-generations that show
lava flows around a place called
Sif Mons). Like Mercury, Earth and
Mars, Venus is mostly rock and
metal.
While all of the planets orbit in an
ellipse (something like the shape
of an egg), Venus' orbit is the
closest to a perfect circle.
Because it is often brighter than
anything in the sky except the
moon, Venus is the cause of many
UFO reports.
EARTH
• The Diameter of
earth is 7,926 miles.
• It takes 23 hours, 56
minutes for the
earth to rotate
completely.
• It takes 365.24 days
for the earth to Orbit
around the sun.
Cool facts about Earth
• Earth is the third planet from
the sun. Like the other three
planets of the inner solar
system (Mercury, Venus, and
Mars) our planet is made up
mostly of rock and metal.
• One of the most important
things about Earth is that
there's lots of water, which is
one important reason why
life got started long ago.
We're also lucky that Earth's
atmosphere has plenty of
nitrogen and oxygen, two
other things that life needs.
• It may not feel like it but
the ground under your
feet is actually moving
very, very fast. The
Earth's surface is rotating
about its axis at 1,532
feet per second at the
equator, and the planet
zips around the sun at
more than 18 miles per
second! So all of us are
going incredibly fast -even when we're
standing still.
MARS
• The diameter of Mars is 4,217
miles.
• It takes 24 hours and 37
minutes for it to rotate 360
degrees completely.
• It takes 687 days for mars to
completely orbit the sun.
• It only has 5% of the mass that
the earth has.
• It has 53% of the earths
diameter.
• It’s 150% further away from the
sun than the moon is.
Moons of Mars
• Mars has two moons
• Phobos
• Diemos: both are sons of
Ares (god of
bloodlust/war) and
Aphrodite (goddess of
love) in Greek Mythology
• Both are believed to be
captured asteroids from
the nearby asteroid belt
THE “LOW DOWN” ON MARS
• The fourth planet from the sun
has always made us humans
do a lot wondering and hoping.
While scientists haven't proven
there's any life on Mars, the
dusty red planet is still a
fascinating place.
• The surface of Mars is more
interesting than most. Like
Mercury, Venus and Earth,
Mars is mostly rock and metal,
but it also has lots of
mountains and craters.
• The dust that gives Mars the
reddish color is made of
something called iron oxide.
Temperatures on Mars can get
as cold as -207 degrees
Fahrenheit and as high as 80
degrees Fahrenheit on
summer days.
• Mars was probably warm and
wet about 3.7 billion years ago.
Mars cooled and the water
froze. Some of that water still
may exist in ice caps at the
poles.
The Asteroid Belt
• Asteroids are small bodies that
are left over from the beginning
of the solar system
• They are rocky objects with
round or irregular shapes up to
several hundred km across,
but most are much smaller.
• May be the remains of an early
planet which broke up.
• The chances of an asteroid
colliding with Earth are very
small! But some do come close
to Earth, like Hermes (closest
approach of 777,000 km).
JUPITER
• Jupiter weighs over 316
times as much as the
earth.
• It is also 11.12 times
larger than the earth.
• The fifth planet from the
sun is mostly a huge ball
of gas. But at Jupiter's
center is a core of rock
many times the mass of
Earth. The whole planet
is so massive it could
hold all the other planets
put together!
Jupiter as a star?
• It is quite interesting that the composition of Jupiter is very much like our Sun.
Jupiter is 89 percent hydrogen and eleven percent helium. The Sun: 78 percent
hydrogen and 19.8 percent helium.*
• Jupiter does radiate about twice as much heat energy as it receives from the Sun,
but this heat comes from an internal reservoir left over from the planet's birth
some 4.6 billion years ago. The Sun produces it's heat energy through nuclear
fusion.
• The Simple Answer: not enough mass, Jupiter is too small to be a star.
Jupiter’s Moons
• Has 63 moons
• Galileo discovery
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Four Largest
Europa: ice? Life??
Io: active volcanism
Callisto
Ganymede
SATURN
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Diameter: 74,900 miles
Time to rotate completely: 10
hours, 39 minutes
It takes 29.5 years for saturn
to orbit the sun.
The sixth planet from the sun
has a rocky core and a lot of
gas on its surface. But Saturn
is known for its rings. The
mile-thick rings are made of
tons and tons of ice that orbit
the planet. Some of the ice
bits are smaller than marbles,
some are bigger than your
computer.
Saturn has 18 known moons,
each made mostly of ice and
rock.
Moons of Saturn
• Has 60 moons
• Titan has an
atmosphere
• Mimas looks like the
Death Star (Star
Wars) from an impact
crater
URANUS
•The diameter of Uranus is 31,763 miles long.
•It takes the planet 17 hours and 54 minutes to turn 360 degrees.
•It takes 84 years for uranus to orbit the sun.
•It weighs 14.5 times as much as the earth
•It is 4.1 times heavier than the earth
•The seventh planet from the sun is a lot like its neighbors, with a cloudy
surface, rapid winds, and small rocky core.
•Uranus rotates at an extreme tilt of 98 degrees, sort of on its side. This
causes one pole to point toward the sun for decades, giving the planet
strange seasons. Scientists think the planet might be on its side because
some other large object crashed into it a long time ago.
Moons and Rings of Uranus
• Has 27 moons,
including Miranda,
Puck, all of them are
icy
• Complex ring system
• Remember, it also
rotates on its side
The Kuiper Belt
• Region of the Solar System extending beyond the
planets extending from the orbit of Neptune to the outer
edge of the solar system
• Similar to the asteroid belt, but objects are frozen or icy.
• comets: lumps of ice and dust, tails point away from the
sun, have very long orbital periods.
• Examples of Comets: Halley’s (76 years), Hale-Bopp
(Heaven’s Gate Cult), Shoemaker-Levy (plunged into
Jupiter in 1994).
• Interactive Comet Animation
Kuiper Belt
NEPTUNE
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The eighth planet from the sun
(well, some of the time it's eighth,
but more on that later) has a rocky
core surrounded by ice, hydrogen,
helium and methane.
Like the other gas planets,
Neptune has rapidly swirling
winds. Its quick rotation causes
fierce winds and some very strong
storms. The planet has eight
known moons. Like Saturn,
Neptune has rings. But Neptune's
rings are not as thick, and they are
hard to spot.
Neptune was discovered in 1846.
Neptune has 13 moons
• Largest moon is
Triton, large
compared to the rest
• Some of the others
were discovered so
recently they don’t
have names yet!
PLUTO
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The mass of pluto is .2% of the earth.
The diameter is only 18% of what the
earths is.
Pluto, which is smaller than our moon,
is a cold, dark, frozen place. We don't
know very much about the tiny planet.
Scientists think it is made of rock and
ice. It might have a thin atmosphere of
nitrogen, carbon monoxide and
methane.
Some astronomers think Pluto may
have wandered into the system from a
more distant place called the Kuiper
Belt. In the Kuiper Belt, Pluto-like
objects and comets orbit the sun. So
maybe Pluto is not a planet at all, but
more like a large asteroid or comet.
Some scientists say Pluto may be an
old moon of Neptune that escaped.
Inner Planets
Planets
w/ Sun
Sun w/ other Low Mass Stars
Sun w/ High Mass Stars