2.3 Using Space Technology to meet Human Needs on Earth. SATELLITES Satellites—sometimes referred to as “artificial satellites”—are objects that are built and sent into Earth’s orbit by humans. They transmit the information using radio waves (topic 3) They can help us: communicate Observe forecast weather predict magnetic storms find our location on the planet (GPS) Satellites keep us: entertained (tv & radio) on course (navigation) Up to date (remote sensing) Satellites can even tell us where the nearest gas station or give you directions to an certain address. What are some obvious advantages and disadvantages to this type of technology?

2.3 Using Space Technology to meet Human Needs on Earth. 1. Communication Satellites Provide ‘wireless’ technologies for a wide range of applications. Digital signals have resulted in clearer communications and more users. Anik 1 (launched by Canada in 1972) transmitted the first television broadcasts by satellite. Figure 2.24 Launched in 1972, Telesat Canada’s Anik 1 provided Canada with communication across the entire continent. Canada was also the first country in the world to use satellites to transmit television broadcasts.

2.3 Using Space Technology to meet Human Needs on Earth. Satellites for Observation and Research A geosynchronous orbit is one that enables a satellite to remain in a fixed position over one part of the Earth, moving at the same speed as the Earth. Weather satellites are usually geosynchronous. Therefore the weather satellite can monitor the same area at all times. Non-geosynchronous observation satellites can be used to monitor specific activities on earth. Canadian satellites, LANDSAT and RADARSAT (are not in geosynchronous orbit) perform the following tasks: follow ships at sea monitor soil quality track forest fires report on environmental change search for natural resources. Military and government surveillance

2.3 Using Space Technology to meet Human Needs on Earth. Remote Sensing Remote sensing is a process in which imaging devices in a satellite make observations of Earth’s surface. Images can be photographs taken by cameras or data collected from the sensing of heat and other invisible energy waves. Remote sensing can provide information on the condition of the environment, natural resources, effects of urbanization, and even the effects of a natural disaster (Tsunami) http://www.globalsecurity.org/military/world/indonesia/aceh-andaman-tsunami_comp04.htm http://www.weather.gov/sat_tab.php?image=ir

2.3 Using Space Technology to meet Human Needs on Earth. Satellites as Personal Tracking Devices ( GPS ) The Global Positioning System (GPS) allows you to know exactly where you are on the Earth at any one time. The system involves the use of 24 GPS satellites positioned in orbit, allowing for 3 to always be above the horizon to be used at any one time. The three GPS satellites provide coordinated location information, which is transmitted to a GPS receiver (hand-held) to indicate the person’s exact position on the Earth.

“SPACE AGE” INSPIRED MATERIALS AND SYSTEMS Figure 2.29 Not all of the technology created for exploring or living in space is used only in space. The fireresistant suits and compact breathing apparatus used today by firefighters are spinoffs from innovations developed for NASA astronauts.

Check & Reflect Questions 1-8 page 432 Homework Assignment In brief point-form style copy and paraphrase the information in the table of ‘spin-offs’ on p. 431 Check & Reflect Questions 1-8 page 432