Transcript Solar System Presentation

The Solar System
The Solar System
• According to Aug 24, 06
Resolution the Solar System
is composed of:
– Eight planets with their
moons
– Three dwarf planets with
their moons
– Small Solar System bodies
• The major features of the
Solar System are:
– The Sun
– Terrestrial (inner) Planets
– Inner Belt of Asteroids
– Gas Giant (outer) Planets
– Outer Belt of Small
Bodies (Kuiper Belt)
Heliocentric System
• Nicolaus Copernicus
developed a sun-centered
system called a heliocentric
system.
• The Earth and the other
planets revolve around the
sun.
• Galileo was the
first scientist to
use a telescope
to look at objects
in the sky, which
supported
Copernicus’s
theory.
• Johannes Kepler, a German
mathematician, discovered
that the orbit of each planet
is an ellipse.
• Isaac Newton
concluded that
two factorsinertia and
gravity combine to
keep the
planets in
orbit.
The Sun
• The Sun
(Sol)
contains
99.8% of the
Solar
System’s
known mass.
• The Sun dominates the Solar
System gravitationally.
• The Sun consists of 70%
hydrogen, 28% helium, and 2%
metals. It’s energy is sustained
by nuclear
fusion reactions,
converting
hydrogen into
helium and
energy.
• The Sun releases enormous
amounts of energy. Most is
sent into space as radiation,
including visible light.
• The Sun
radiates
a
plasma
known
as solar
wind.
Definition of Planet
• A “planet” is a celestial body that:
– is in orbit around the Sun;
– has sufficient mass for selfgravity so it assumes a nearly
round shape; and
– has cleared the neighborhood
around its orbit.
Final International Astronomical Union Resolution, Aug 24 06
The Inner Planets
• The four inner
or terrestrial
planets are
dense, rocky,
have few or no
moons, and lack
ring systems.
Mercury
• Closest planet to
the Sun and least
massive of the
planets. It has a
very thin
atmosphere and
has no natural
satellite.
Venus
• It’s atmosphere is
90 times as dense
as Earth’s and
composed of
carbon dioxide. It
has no natural
satellite and is the
hottest planet.
Earth
• Largest and densest
of the inner planets.
Only inner planet
with evidence of
geological activity
and liquid
hydrosphere. Has
one satellite, the
Moon.
Mars
• Less massive than
Earth or Venus. Has
a carbon dioxide
atmosphere. It’s
surface contains
volcanoes and rift
valleys. Has two
satellites: Deimos
and Phobos.
The Inner Belt
• Made of mostly small solar system
bodies of rocky minerals.
Occupies the orbit between Mars
and Jupiter.
Asteroids
• Small solar
system bodies
found mainly in
the Asteroid
Belt with
elliptical orbits
between Mars
and Jupiter.
Meteoroid
• Smaller than asteroids. A meteor is
a meteoroid that has entered the
Earth’s atmosphere. A meteor that
survives impact is called a
meteorite. Meteors can produce
impact craters.
Ceres
• Largest body in the
asteroid belt and
only known dwarf
planet in this
region. It is
spherical and
contains a third of
the belt’s total
mass.
The Outer Planets
• The four outer planets or gas
giants together make up 99% of
the mass known to orbit the Sun.
The Outer Planets
• All four of the
gas giants have
orbital debris
rings. Only
Saturn’s rings
are observable
from Earth.
Jupiter
• Is at 318 Earth
masses. Composed
of hydrogen and
helium. Has large
cloud bands and
the Great Red Spot.
It has 63 satellites,
the largest is
Ganymede.
Saturn
• Has an extensive ring system. Also
composed of hydrogen and helium.
Has 56 satellites and largely made
of ice. Titan is larger than Mercury.
Uranus
• The lightest of
the outer planets.
It orbits the Sun
on its side (axis
is 97o to the
ecliptic). Radiates
very little heat.
Has 27 satellites.
Neptune
• Smaller than Uranus
but is denser and
more massive.
Radiates more heat
than Uranus. Has 13
moons; the largest
Triton revolves
clockwise around
Neptune.
The Kuiper Belt
• A great ring of debris,
similar to the asteroid belt.
Composed mainly of icy
small solar system bodies.
Often called the outer solar
system or “trans-Neptunian
region.”
• The Kuiper Belt is possibly the
place of origin for short term
comets, such as Halley’s comet.
Some objects are affected by
Neptune’s orbit.
Comets
• Small solar system
bodies composed
largely of ice.
When a comet
approaches the
Sun the surface
boils away creating
a coma (tail of gas
and dust).
Pluto
• The largest known
object in Kuiper
Belt. Reclassified
as a dwarf planet.
Charon orbits
Pluto more like a
binary system. Nix
and Hydra orbit
Pluto and Charon.
Eris
• Largest known
scattered disk
object (overlaps
the Kuiper Belt).
5% larger than
Pluto. The largest
known dwarf
planet. Has one
moon, Dysnomia.
The Solar System