Science Thursday, October 29, 2015Thursday, October 29, 2015Thursday, October 29, 2015Thursday, October 29, 2015 Technological Developments and the Exploration of Space

2.1 – Getting There: Technologies for Space Transport  To escape the pull of Earth’s gravity an object must travel at a speed greater than 28,000 km/h (18,000 mph)  Therefore, to launch spacecraft and satellites into space, we need powerful rockets

Early Rockets  Robert H. Goddard was the first person to successfully launch a liquid-fuel rocket in 1926  This rocket would serve as a prototype for all other major rocket designs

The German V-2  In 1942, Werner von Braun and his team of researchers designed the V-2 liquid fuel rocket, which was the first rocket to ever leave the atmosphere  After World War II, von Braun worked for the United States in its space program

Sputnik  On October 4, 1957, the Soviet Union launched the first manmade satellite, Sputnik  One month later, the Soviets launched a dog named Laika into orbit

Vostok and Mercury  Yuri Gagarin became the first person in space in 1961 aboard Vostok 1  Alan Shepard was the first American to enter space later that year

Gemini  The American Gemini program involved more advanced work, such as spacewalks and docking with other craft during flight

Apollo  The purpose of the Apollo program was to land a person on the surface of the Moon  This was accomplished on July 20, 1969

Skylab  Skylab was the first space station to orbit the Earth  In 1973 and 1974, three missions visited the space station  It crashed into the sea near Australia in 1979  The Australians fined the US $400 for littering (the fine has not yet been paid)

The Space Shuttle  In 1981, the first Space Shuttle was launched  This new vehicle was reusable – previous rockets used single-use capsules

Rocket Engines  A rocket engine relies on Newton’s 3 rd Law of Motion – For every force there is an equal and opposite force  In a rocket engine, the force of expanding gases from combustion pushes down through the engine nozzle, and the rocket moves in the opposite direction

 Rockets consist of 3 parts: 1. Structural and mechanical elements, such as the engines, storage tanks, and fins 2. The fuel, which may vary in form and composition 3. The payload, which may include people, food, water, air, or machinery

Current and Future Propulsion Systems  Current rockets use liquid fuels, such as hydrogen and oxygen  Future spacecraft may use ion propulsion, where electrically charged xenon is accelerated by an electric field

 The ion drive produces very little force, but that force is sustained over a long period, producing great speed  These types of drives could be used to move vehicles in space, not to launch them from the Earth  Solar sails may also be used  These consist of a large, thin reflective surface that uses the momentum of photons from the Sun like a wind  This would cause the ship to move

2.2 – Surviving There: Technologies for Living in Space  Space is a hazardous place to live  Planned missions to Mars would require living in a hostile environment for two or three years

Environmental Hazards  Space is a vacuum, with no air or water  As well, deadly radiation and the risk of meteoroids are constantly present  Temperatures in space can rage from extreme heat to freezing cold  In the vacuum of space, our heart would not beat and the low pressure would cause your blood to boil instantly

Psychological Challenges  On a long mission, crew members would have to live in very close quarters (less than the size of this room) for months or years  This can lead to psychological problems

The Body and Microgravity  The human body is not designed for a microgravity environment  In weightless conditions, bone density is lost and muscles tend to weaken because of the lack of force  The effect of weightlessness is being studied aboard the ISS

Space Suits  Space suits are specially designed to keep astronauts alive in the vacuum of space  They provide air, water, heating and cooling and even a portable toilet

Living in Space  Because it is inefficient to constantly provide new materials to a space station, many things are recycled  The ISS uses devices that can recycle 100% of the water in the station  The Environmental Control and Life Support Systems aboard the ISS have a number of functions:

1. Recycling of water to produce drinking water 2. Using recycled water to produce oxygen (through electrolysis) 3. Removing CO 2 from the air 4. Filtering micro-organisms and dust from the air 5. Keeping air pressure, temperature and humidity stable

ISS Recycling

Using Space Technology to Meet Human Needs on Earth  We can use space technologies here on Earth  One of the main ways that we use this technology is through Satellites

Communication Satellites  In the early 20 th century, telegraph and telephone messages traveled through wires  Today we use digital signals from satellites that allow clearer transmissions and a larger number of users

Observation and Research Satellites  Geosynchronous satellites (those that maintain a constant position) are used to monitor weather  Other satellites, such as LANDSAT and RADARSAT can track ships at sea, forest fires, environmental damage, and natural resources

Remote Sensing  The main purpose of satellites in low Earth orbit (200 to 1000 km altitude) is to make observations about the Earth  This provides information about the condition of the environment, natural resources, and the effects of urbanization

The Global Positioning System  There are 24 GPS satellites that orbit the Earth  At any one point, there are at least three of these satellites that are above a given location at any moment  They produce radio signals that are picked up by receivers

 These radio signals contain time information  The time information from each satellite is compared with the internal clock on the receiver, and the time difference between the signals indicates the distance from the satellite  When three signals overlap, they will provide the user with their position

 The GPS was originally developed for the US military  In 2000, non- military users could finally receive a full- quality signal (prior to this, civilians could only receive a less accurate signal)

Space Age Materials and Systems  Many different materials and systems originally designed for space have been put to use on Earth  Almost all sectors of business have been advanced through the use of these materials and technologies:

Computer Technology  Computers have been used to analyze the structure of spacecraft, the monitoring of onboard systems, and the training of astronauts  On Earth we use the same technologies in offices, to analyze buildings and bridges, and to develop virtual reality software

Consumer Technology  Astronauts use specialized foods in space, and much work has been put into the studies of insulation and aerodynamics  We now can buy many enriched freeze-dried foods  New, more efficient designs of bike helmets, golf balls, running shoes and ski goggles are the results of the work done to improve spaceflight

Medical and Health Technology  Motion sickness is a problem in space, so medications were developed to counteract it  As well, digital imaging that was developed for satellites is now used in medicine to detect cancers

Industrial Technology  Lasers are used for communication in space, and they are now used for communication and manufacturing here on Earth as well

Transportation Technology  Special materials that were used in parachutes and spacecraft are now used in automobile designs, even down to the tires!

Public Safety Technology  A large amount of our exploration in space is done by robots because it is too dangerous for humans  Robots with similar designs are now used for similar tasks on Earth (such as the disposal of explosives)

The End