Transcript 13.12 & 14.6 Technolgy and Space

Technology and Space
(13.12, 14.6)
BLM 13.12
Space Probes
Space probes are useful for exploring the
outer planets and moons.
They are generally pilot-less because they
are too expensive and humans cannot
presently survive that long in space.
(They can survive, but the long term
effects are not known.)
It took almost a year for a probe to get to
our closest planet, Mars.
Some Probes Info Chart
Name
Launch yr. Return yr. Details
Some Probes Info
Pioneer 10: 19722002 last contact.
Voyager 1/2: 1977Sent back images from planets and moons.
Magellan: 1989-1995
Mapped Venus, was crashed into the planet in
1995 on purpose.
Galileo: 1989Flew past target asteroids ’91-92, explored
Jupiter and its moons in ’95, Winds of Jupiter
are thousands of km above surface.
Some Probes Info
Mars Global Surveyor-Pathfinder: 1996 landed 1997
Surveyor is orbiting Mars for atmosphere.
Pathfinder landed and released Sojourner
that explored the surface.
Cassini: 1997- landed on Saturn 2004
Exploring Saturn and its largest moon Titan.
Expected to keep travelling until 2008.
Mars Global Surveyor-’98: 1998 – 2000
Climate Orbitor (98) and Polar Lander (99)
were supposed to search for water in
atmosphere and on land but they crashed.
How do they get there?
We all know how big the tanks are on the
shuttle just to get it to the space station.
Can you imagine how big they have to be to get
to Mars or outer planets if they needed
constant propulsion…
They don’t though!
Think of an Olympic Hammer Thrower.
You spin and spin the hammer then release it
and it goes out.
How do probes do this?...
BLM 13.12
Release of Probes and p.422 (2)
Basically, probes are launched then they
orbit the Earth until they are going so
fast the gravity can’t hold it anymore.
It is released and then rotates or gets
pulled by next planet’s gravity.
2. State reasons why space probes are
usually unpiloted?
Unpiloted spacecraft are safer and cheaper.
Radio Telescope in BC
Telescopes 14.6
Read pages 448-450:
Do questions 1, 2, 3 and…
4. What is a radio telescope?
5. What is an infrared telescope?
Canada-France-Hawaii Telescope
Telescopes Answers
1.
The main purpose is to gather light. This
gathering of light forms images.
2. A refracting telescope bends the light
through a gathering lens and focuses it at
the eye piece. They are limited in size
because the lens is at the top.
A reflecting telescope uses a concave mirror
at the bottom of the scope.
3. a) The ozone layer distorts the image.
b) You can build an observatory very
high up on a mountain where the
atmosphere is thin or place in space
where there is no atmosphere or in
space (Hubble telescope).
4. A radio telescope picks up the radio
waves given off by distant stars and
planets.
It is good because radio waves penetrate
the atmosphere, so the telescope works
on a cloudy days unlike light telescopes.
5. An infrared telescope (like IRAS) picks
up small heat sources (very small). These
are good for finding non-luminous
objects with weak radio
waves.