Physics- Space

• planets definition- large ball of matter that orbits a star
• Dwarf planet definition- A body orbiting the sun that does not meet the criteria for a planet
• Moon definition- A natural satellite of the Earth, orbiting around it, that is made of rock and metal.
• Sun definition- The star at the centre point of our solar system
• Asteroid- A large rocky body orbiting the sun that is not a planet.
• Solar system definition- A collection of planets and a star
• Star definition- A large ball of gas held together by gravity.
• Exoplanet definition-
• Galaxy definition- A collection of stars that orbit a centre point
• Universe definition- Many galaxies separated by empty space
• Light year definition- The distance light travels in a year.
• Challenge of space travel- it is a large distance so travelling to mars would take months
• Challenge of space travel- The energy required for the fuel for launch for overcoming earths gravity and to generate enough thrust to escape
• Challenge of space travel- No air friction meaning manovering objects is difficult. Thrusters can make an object move but even when the thruster is turned off it will continue to move in that particular direction at constant speed. To stop two opposite thruster would need to be fired
• Risks of space travel- Micrometeorites, the danger of impact damage to the spacecraft and when the astronauts go on space walks
• Risks of space travel- Cell and DNA damage from solar flares and radiation
• Risk of space travel- The temperature vary from being really cold (-150) to very hot (120) . The astronauts suits and spacecraft is built for the living conditions we are used to.
• Risks of space travel- The re-entry of the space craft is very fast through the air which creates high frictional forces that produces very high temperatures so the space craft has heat proof tiles on underside
• Risk of space travel- the fuel load of fuel may cause explosion on take off
• Light year equation- D=v/t
• Spped of light= 3x10^8 m/s
• Time in a year- 60 times 60 times 24 times 360 (seconds, hours, days, year)
• The big bang theory- The universe came to existence as a singularity and rapidly expanded from an extremely hot dense state to what we know today
• The big bang theory- A bit of evidence is that the stars and galaxies that we know of are continuing to move away from us that suggests we were once a single point
• What we can use satellites for- GPS, weather, communications, space exploration
• Period of satellites- when a satellites time taken to orbit the planet, the higher altitude the satellite is the longer a period will take to orbit. Satellites experience constant vertical acceleration and velocity
• Geostationary satellite- when a satellite is orbiting at 36,000km above the earth which is equivalent to one year
• Light spectrums- Continues spectrum is a white light refracted using a prism to produce a smooth rainbow of every wavelength of light
• Light spectrums- Line spectrums- each element emits only specific wavelengths of light. The spectrum is made up of line of colour. Each element produces a specific pattern