Space Science

1
Space Science

• E.Q. What are the relationships between and
  among the objects of our solar system?

2
Earth in Space

• Earth moves through space in two ways rotation
  and revolution
• Rotation spinning on its axis
• Revolution movement of earth around another
  object
• Earth follows a path called orbit
• Earths orbit is an ellipse, around the sun

3
Observing the Solar System

• Geocentric systems - Earth is at the center of
  the revolving planets and stars
• Ptolemys model showed the planets moving on
  small circles that move on bigger circles
• Heliocentric systems - Earth and the other
  planets revolve around the sun
• Copernicus figured the arrangement of the known
  planets and their movement around the sun
• Galileo made discoveries about Venus phases that
  prove the heliocentric model
• Tyco Brahe and Johannes Kepler discovered the
  elliptical orbits of the planets

4
Earth in Space

• Earth has seasons because its axis is tilted as
  it revolves around the sun.
• Earths axis is tilted at 23.5 degrees from
  vertical.
• Solstice when sun is farthest from equator
• Equinox when sun is directly over the equator

5
Gravity and Motion

• Gravity attracts all objects toward each other.
• Newtons Law of Universal Gravitation states that
  every object in the universe attracts every other
  object.
• The strength of the force depends on
• Masses of each object
• Distance between them
• Gravitational force (G m1 m2) / (d2)
• G is the gravitational constant, m1 and m2 are
  the masses of the two objects for which you are
  calculating the force, and d is the distance
  between the centers of gravity of the two masses

6
Gravity and Motion

• Mass is the amount of matter in an object
• Weight is the force of gravity on an object
• Inertia is the tendency of an object to resist a
  change in motion
• For Orbital Motion inertia and gravity combine
  to keep Earth in orbit around the sun, same for
  moon

7
Phases, Eclipses, and Tides

• Phases - Caused by the change in relative
  positions of the sun, moon, and earth
• Phases different shapes of the moon (as viewed
  from Earth)?
• The moon rotates and revolves around the earth
  once every 27.3 days.
• The phase cycle is about once every 29 days. (the
  difference is because the earth changes position
  relative to the sun during that same period.)

8
Phases, Eclipses, and Tides

• Observe Eclipse
• Eclipse when one object moves into the shadow of
  another
• Solar Eclipse is when moon passes directly
  between Earth and the Sun during new moon
• Total Solar Eclipse - when the umbra obscures
  light from a point on Earth
• Partial Solar Eclipse when the penumbra casts a
  dim shadow on Earth only part of the sun is
  visible
• Lunar Eclipse is when Earth blocks sunlight from
  reaching the moon only during full moon
• Total Lunar Eclipse when the moon is in the
  Earths umbra
• Partial Lunar Eclipse when the moon is
  partially in the Earths umbra

9
Phases, Eclipses and Tides

• Tides are caused by the differences in the moons
  gravity pulling on Earths bodies of water.
• High tides occur on points of Earth closest and
  furthest away from the moon low tides occur at
  points between the two high tides
• Spring Tide When the sun and moon align in any
  order Largest difference between consecutive low
  and high tides
• Neap Tide Suns pull is at tight angles to the
  moons pull least difference between consecutive
  low and high tides

10
Earths Moon

• Observe YouTube - First Moon Landing 1969
• Features on the moons surface
• Maria dark flat areas, hardened rock from lava
  flows
• Craters large round pits from meteoroid impact
• Highlands - light colored features which are
  mountains, cover most of the moons surface
• Dry and Airless
• Moons diameter is ¼ Earths diameter

11
Earths Moon

• Moon has 1/80 the mass of Earth
• Temperatures range from 130 C to -180 C, Why the
  large difference?
• No liquid water, Ice maybe? Where?
• Rotates and revolves once every 28.5 days

12
Earths Moon

• Moons Origin Collision-Ring Theory
• 4.5 bya Solar system full of rocky debris
• Planet sized object collided with Earth
• Material was ejected into Earths orbit
• It formed a ring and gravity caused it to combine
  and form the moon
• Density and Origin?

13
The Sun

• Black Hole Sun
• Suns interior consists
• Core Produces enormous amount of energy from
  nuclear fusion hydrogen atoms join together to
  form helium
• Radiation Zone very tightly packed gas energy
  transmitted as electromagnetic radiation
• Convection Zone outermost layer of suns
  interior loops of gas in convection currents

14
The Sun

• Suns Atmosphere
• Photosphere gives off visible light
• Chromosphere middle layer
• Corona looks like a white halo around the sun
  means crown
• Extends for millions of kilometers
• Gradually thins into solar winds streams of
  electrically charge particles

15
The Sun

• Suns Features
• Sunspots areas of gas on the surface that are
  cooler than the surrounding gas
• Prominences huge reddish loops of gas
• Solar Flares energy heats gas to millions of
  degrees Celsius causing gas to erupt
• Sun features

16
The Inner Planets

• Four Inner Planets called terrestrial planets
• Small, dense, rocky
• Mercury
• Smallest inner planet
• Many flat plains and craters
• No atmosphere due to weak gravity
• Greatest temperature range of any planets
• Venus
• Density and structure similar to Earths
• Thick atmosphere made of carbon dioxide always
  cloudy
• Pressure of atmosphere is 90 times that of Earth
• Avg. surface temp. 460 C
• Greenhouse effect - Thick atmosphere traps heat

17
The Inner Planets

• Earth
• Three layers Crust, mantle, core
• Has water in all three states on surface
• Atmosphere mostly of nitrogen and oxygen
• Largest of terrestrial planets
• Mars
• Called Red Planet
• Thin Atmosphere mostly of carbon dioxide
• Olympus Mons largest volcano in solar system
• Temperatures range from -140 C to 20 C
• Has water as ice on surface at poles

18
The Outer Planets

• Four Outer Planets called Gas Giants
• Jupiter
• Largest most massive planet
• Thick atmosphere mostly hydrogen and helium
• Great Red Spot a storm larger than Earth
• 18 Named Moons include Callisto, Io, Ganymede,
  Europa
• Saturn
• Ring made of ice and rock
• Thick atmosphere mostly hydrogen and helium
• 18 moons Saturns largest moon Titan

19
Outer Planets

• Uranus
• 15 moons
• Rotates at an angle about 90 degrees from
  vertical
• Surrounded by group of thin flat rings
• Neptune
• Cold blue planet
• 13 moons largest moon Triton

20
Traveling into Space
21
Comets, Asteroids, and Meteors

• Observe Meteor Hitting Earth
• Comets - loose collections of
• ice
• Dust
• small rocky particles
• Orbits are long narrow ellipses
• Coma fuzzy outer layer - cloud of gas and dust
• Nucleus the solid inner core
• Tail stream of gas and dust points away from
  the sun
• Origin
• Kuiper Belt a doughnut shaped area beyond
  Neptunes orbit to 100 times Earths distance to
  the sun
• Oort Cloud spherical region out to 1,000 times
  Plutos distance to the sun

22
Comets, Asteroids, and Meteors

• Asteroids rocky objects with diameters between
  a few and several hundred kilometers
• revolve around the sun between Mars and Jupiter
• More than 100,000 discovered asteroids
• Ceres, Pallas and Vesta are largest (300 km
  across)?
• Could hit Earth
• Meteors - Chunk of rock or dust in space
• Come from comets or asteroids
• Meteor - a meteoroid that enters Earths
  atmosphere
• Meteorites - meteoroids that pass through Earths
  atmosphere and hit Earth

23
Is There Life Beyond Earth?

• Extraterrestrial Life life other than that
  which exists on Earth
• Goldilocks Conditions just right
• Liquid water
• Suitable temperature range
• Atmosphere
• Extreme Conditions
• Life found near
• Springs with near boiling temperatures
• Bottom of the Ocean under extremely high pressure
• Animals that get their energy from chemicals

24
Is There Life Beyond Earth?

• On Mars
• May have once had the conditions needed for life.
• Europa
• If there is liquid water on Europa, there might
  also be life.
• SETI Search for Extraterrestrial Intelligence
• http//www.exploremarsnow.org/

25
Telescopes

• Light is a form of electromagnetic radiation
• Energy that can travel through space in the form
  of waves
• Visible light
• Hubble Space Telescope

26
Characteristics of Stars

• C

27
Lives of Stars
28
Star Systems and Galaxies
29
The Expanding Universe