BellringerWhat is the amount of energy a sound wave

carries per second through a unit area called?

Using Space Science on Earth

Notes

The Challenges of Space

• A vacuum is a place that has no matter. Most of space is a vacuum. Because there is no matter, there is no pressure.

• Exposure to a vacuum results in swelling of the body (ebullism) and the prevention of O2 from reaching the brain. The astronaut passes out within seconds, and could die within 2 minutes if pressure is not restored.

• Chances of survival are greater if the astronaut is NOT holding his/her breath when exposed to a vacuum.

Normal Atmospheric Pressure

Marshmallows in a Vacuum

The Challenges of Space

•There is no air in space, so astronauts must carry their own oxygen to breathe.

•Also, because there are no gases in space to hold the sun’s heat, temperatures in space are usually very low.

•But because you can not conduct or convect heat away from the body in space (these processes require matter to work), death by freezing would be unlikely.

The Challenges of Space

•A feeling of having no weight is called microgravity. Astronauts in orbit around Earth must interact with others and their surrounding in this microgravity environment.

Space Spinoffs

•A space spinoff is something that was designed for space but is now used on Earth. Space spinoffs include things you can buy in stores. They also include new materials and medical devices.

Space Spinoffs

Space Spinoffs

Space Spinoffs

Space Spinoffs•Due to the isolated nature of space, many

inventions were created by NASA to make the astronauts as independent as possible.

•Cordless devices had to be created because there are no plugs in space.

• In an effort to make the shuttle and its components lighter, and yet remain strong, new materials were developed that are now used in modern sports and medical equipment.

Space Spinoffs•To protect the astronauts from

harmful solar radiation, new highly efficient insulating materials were developed. These materials are now being used in houses, cars, and trucks.

•Fireproof materials developed for spacesuits are now used in modern firefighting equipment.

Space Spinoffs•NASA also helped to develop the

technology that we now use in modern pacemakers. These pacemakers use a sophisticated long-life battery that was originally designed to help supply power to systems in the shuttle and space station.

•Lasers used to clear arteries of clogs, as well as the technology for CAT scans were developed by NASA.

Satellites• There are over 700 artificial satellites (and one

natural satellite) that are currently in orbit around Earth. These satellites include observation satellites and communications satellites.

• The purpose of an observation satellite my be to track weather on Earth, used as spy satellites for the military, or used to collect pictures for Google Earth. Observation satellites collect data using remote sensing.

• Remote sensing is when information about Earth and other space objects is collected without direct contact.

Lake Chad, 1963 Lake Chad, 1997

Satellites

•The purpose of communication satellites is to relay signals from one part of Earth to another.

•Because EM signals travel in only straight lines, they cannot travel around the curvature of Earth. Therefore, they send the signal straight up to a satellite, which will then send it down to its destination, or to another satellite.

•These signals include television signals, radio signals, and telephone signals.

Satellites• A satellite has one of two orbits that it can be

placed in: LEO and GEO

• LEO is Low Earth Orbit.

• LEO is between 160 and 1200 km from Earth’s surface.

• Placing a satellite in this type of orbit will allow it to be maneuvered around the planet as needed.

• Which satellites might benefit from being able to move around the planet?

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sLEO

Satellites•GEO is a geostationary orbit.

•Geo means “earth” and stationary means “not moving.”

•These satellites are located directly above the equator of the planet and appears to be stationary when viewed from Earth.

•Which satellites would we want to be stationary at all times?

•http://upload.wikimedia.org/wikipedia/commons/3/3a/Geostationaryjava3Dsideview.gif