Transcript Exploring Space

Chapter 18 Exploring Space
Section 1 Observing the Sky
How do we observe space from Earth?
•Un-aided eye
•Binoculars
•Telescopes
Most ancient astronomers spent
countless nights observing and
mapping the sky.
Early Astronomers
Early Astronomers
•Ptolemy
•Copernicus
•Brahe
•Kepler
•Galileo
•Newton
•Hubble
Your homework
assignment: Write a
summary statement
about the contributions
of each scientist to
early astronomy.
Telescopes
Single purpose
of telescopes is
to gather and
focus light!
Telescope video
9 minutes
Optical Telescopes
Refracting Telescope- uses convex lenses to
magnify objects in space
Large ones no longer built because lenses
will distort over time due to gravity. Small
ones good for beginners
Reflectors
Reflecting Telescopes- uses MIRRORS and eyepiece lens to
magnify.
Better quality,
easier to build
big ones.
MMT (Multiple Mirror Telescope) - reflector with many
mirrors.
High quality, combine smaller
mirrors for image
Hubble space TelescopeHighest quality, no
atmosphere to distort light,
very dark!!!
Tips for using telescopes
•Get on a hilltop or mountain peak
•Get away from any lights
•Must be clear!! Best if it is really
cold!!
Limitations of ground based
Telescopes
Telescope viewing distortions
caused by movement of air
particles in atmosphere and
light pollution.
This is why stars “twinkle:
Atmospheric distortion
Observatories
Kitt Peak Observatory, Arizona
Mauna Kea, Hawaii
Observatories Worldwid
Comparison of Galaxy NGC 1232
World’s largest telescope
Keck Observatory,
Hawaii
Hubble Space Telescope
All objects in space give off
ELECTROMAGNETIC ENERGY
We can only see ROY G BIV, the rest are not visible, but can
be detected with special types of telescopes to learn more
about our universe.
Radio Telescopes
Telescopes that detect radio waves from objects in universe
Benefits over regular telescopes:
•Can be used day or night
•can be used in most weather conditions
•can detect objects not visible in space
Downfalls- not a clear image
Arecibo, Puerto Rico
Largest single telescope in
world
VLA (Very Large Array) New
Mexico
27 dishes over 17 mile area
West Virginia
Other types of telescopes
X-ray
Gamma ray
Infrared
Ultraviolet
All must be detected by telescopes in
space because atmosphere blocks these
wavelengths
iiii
Rocket Science
Our method of
transportation to get into
space is the rocket!
Why can’t regular
airplanes with jet engines
travel to space?
Fathers of Rocket Science
•Tsiolkovsky- developed theory that escaping gas could
generate force to leave Earth’s gravity
•Goddard- launched first liquid fuel rocket 1926
•Von Braun- built V-2 rocket for Germans in WW II ,
defected to U.S. to further aid rocket science
6 minutes
How do rockets work?
Works by Newton’s 3rd Law (Every action has a
reaction)
THRUST created by combustion of fuel under
enormous pressure, gas rushes out of the rocket
Solid Fuel Rockets- Uncontrolled
burn, used for launching rockets
Liquid Fuel- controlled burn, used
to maneuver in space.
How liquid rocket fuel works
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Consists of fuel and oxidizer
Liquid fuel is some form of hydrogen
Oxidizer is some form of oxygen
Oxidizer is used to ignite the fuel
Can be controlled to burn when needed
Solid rocket fuel
• Consists of putty-like mixture of fuel and
oxidizer.
• Once ignited, they cannot be controlled or
stopped.
• Fuel used for initial blast-off of rockets.
Satellites and Space Probes
Satellites orbit Earth, thousands are in orbit today
Sputnik- 1957, 1st satellite by Russians,
Started space race
Space Probes travel out in space and send back
information about planets and moons
Over 50 space probe missions have occurred in last 50
years.
US owns over
400 active
satellites.
About 900 total
active satellites
There are over
26,000 pieces of
space junk (old
satellites and
space craft parts)
Famous Space Probes
Viking
Mariner
Magellan
Pioneer
Voyager
Galileo
Mars Rovers
Cassini
Views from Mars Rovers “Spirit”
and “Opportunity”
Manned Space Missions
Project Mercury- 1958-63, One man
spacecraft
Goals
•orbit a manned spacecraft around Earth
•investigate man’s ability to function in
space
•recover man and spacecraft successfully
Alan Shepard- first American in space
Project Gemini- 1964-1966, Two man spacecraft
Goals:
•test man and equipment for 2 week
space flight
•dock with orbiting vehicles
•land on a pre-selected point
Project Apollo- 1968-1972, Three man spacecraft
Goals:
•to achieve dominance in space
•to go to the moon
•develop man’s capability to work
on the moon
Skylab-1973, Three manned space station
Tested man’s ability to stay in space for extended
periods
Space Shuttle- 1977-present, reusable space
vehicle able to land like airplane
International Space Station-1998-present
U.S. and Russian built.
Space program disasters
Apollo 1- fire on launching
pad, killed 3 astronauts
Columbia- broke apart
upon re-entry, killed 7
Challengerexploded 73
seconds after
liftoff, killed 7