Transcript ESSR_PNE_TheSolarSystems_V01

The Solar System
THE UNIVERSE
The universe is everything physical
that exists in space.
The universe is made up of galaxies
The Sound of the Big Bang - Picture and Sound Clip - MSN Encarta
• The Big Bang Theory suggests the
universe began with a big explosion 15
billion years ago
3 kinds of galaxies
irregular)
A galaxy is a collection of stars,
dust, gas classified by its shape.
• Spiral has a bulge in the dense center
with arms extending outward
• Elliptical is an egg shape with mostly old
stars
• Irregular lacks definite shape
• Our solar system is in the Milky Way
galaxy – a spiral galaxy
The Milky Way Galaxy is a disc about 100,000 light
years across and around 2000 light years thick.
We measure the distance to
planets in our solar system in
astronomical units or light years
The distance from the sun to the Earth is called
an Astronomical unit ( AU)
1 AU = 93 million miles or 150 million kilometers
A light year is a measure of distance, not time.
It represents how far light will travel in one year.
Light travels at about 300 million meters per sec
( 3 X 10 8 m/s) “c”
1 light year = 9.5 X 10 15 meters
It takes light about 5½ hours to travel across the
solar system, so a light year is much bigger
than this
Our solar system consists of the sun, eight
planets, moons, dwarf planets, the asteroid
belt, comets, meteors, and other debris.
The sun is the center of our solar system
ALL planets, asteroids, and comets orbit
the sun.
The SUN is our closest star, it is over 100
• Our Sun is a normal main-sequence G2
star, one of more than 100 billion stars in
our galaxy.
• The next nearest star to us (apart from the
Sun) is Proxima Centauri, which is about
4¼ light years away. Also known as Alpha
Centauri
A planet is a celestial body that
orbits the Sun…
8 or 9?????
My
Very
Educated
Mercury Venus Earth
Mother
Mars
The solar system
Solar System Pictures
Just
Jupiter
Served
Saturn
Us
Uranus
Nine
Pizzas
Neptune Pluto
The Asteroid Belt
An area of 1000’s of asteroids in an elliptical orbit
between Mars and Jupiter.
The Asteroid Belt
separates the inner planets from
the outer planets
Gaspar
Ceres, the largest object in the asteroid belt
•
is a dwarf planet
•
• Asteroids that are on a collision course with
Earth are called meteoroids.
Ceres (lower left) with the Earth
and moon
• This picture shows the sizes of the original three
dwarf planets (Pluto, Ceres, and Eris) as compared
to Earth. It also shows Pluto's large moon Charon
(and its two small moons Nix and Hydra) and
Eris's moon Dysnomia to scale. None of the
distances between objects in this image are to
scale.
Images courtesy of NASA
What happened to Pluto???
READ ONLY:
• In 2006 the International Astronomical
Union (IAU) approved a new classification
scheme for planets and smaller objects in
our Solar System. Their scheme includes
three classes of objects: "small solar
system bodies" (including most asteroids
and comets), the much larger planets
(including Earth, Jupiter, and so on), and
the new category of in-between sized
"dwarf planets".
• There are currently three official dwarf
planets. Pluto, formerly the smallest of the
nine "traditional" planets, was demoted to
dwarf planet status. Ceres, the largest
asteroid in the main asteroid belt between
Mars and Jupiter, was also declared a
dwarf planet. The third and final (for now!)
dwarf planet is Eris, an icy body on the
edge of our Solar System that was
discovered recently in 2005. Eris was
temporarily labeled 2003 UB313 when it
was first discovered, and given the
nickname "Xena", before astronomers
settled on the official name of Eris.
• Both planets and dwarf planets orbit the Sun,
not other planets (in which case we call them
moons). Both must be large enough that their
own gravity pulls them into the shapes of
spheres; this rules out numerous smaller bodies
like most asteroids, many of which have irregular
shapes. Planets clear smaller objects out of their
orbits by sucking the small bodies into
themselves or flinging them out of orbit. Dwarf
planets, with their weaker gravities, are unable
to clear out their orbits.
• Though there are just three dwarf planets now,
their number is expected to grow. Scientists
estimate there may be 70 dwarf planets amongst
outer solar system objects that have been
discovered already. Since we don't know the
actual sizes or shapes of many of the objects
we've found (because they are so far away), we
can't yet determine whether they are actually
dwarf planets or not. More observations and
better telescopes will help us determine which
other objects are dwarf planets. Astronomers
speculate that there may be 200 or so dwarf
planets out through the distance of the Kuiper
Belt, an icy band of frozen planetoids on the
edge of our Solar System.
The outer gaseous planets
planet
Jupiter
Saturn
Uranus
Rotation Diameter atmosph
Dist
From
sun
Period of
5.2
au
11.8
years
9.8
hrs
88729 H, He, -120 63
9.5
au
29.5
years
10
hrs
74600 H, He, -180 18
methane
ring
19.2 84
au years
18
hrs
32600 H, He, -210 15
19
hrs
30200 H, He, -220 2
Neptune 30
au
Revolution (1 day)
miles
ere
(1 year)
165
years
Avg
temp
oK
#
moo
ns
methane
ammonia
ammonia
methane
ammonia
methane
The inner terrestrial planets
Planet
Dist
Period of
Rotation Diameter atmosphe Avg
From Revolution (1 day) miles
re
temp
oK
sun
(1 year)
Mercury
Mercury
Venus
Venus
.4
au
88 days 59
days
3,030 N/A
.7
au
225
days
243
days
7,500 CO2
726 0
H2SO4
Earth
Earth
1
au
3651/4
days
24
7,926 N, O
hours
293 1
Mars
1.5 687
au days
25
4,222 CO2
hours
-150 2
http://www.nineplanets.or
g/mars.html
#
moo
ns
452 0