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: 1972- 2002 last contact. Voyager 1/2: 1977- Sent back images from planets and moons. Magellan: 1989-1995 Mapped Venus, was crashed into the planet in 1995 on purpose. Galileo: 1989- Flew 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 The main purpose is to gather light. This gathering of light forms images. 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.