P1.3 Flashcards
What are galaxies?
collections of stars, held together by the force of gravity
What are landers?
They collect rock samples and do experiments on soil to look for life forms such as bacteria and see if any chemical reactions have occurred.
What is SETI?
Search for Extra Terrestrial Intelligence.
What are rovers?
They take evidence and photographs of rocks and soil from different parts of the planet.
What are space probes?
They orbit planets and take pictures to look for water and see if it has conditions for a suitable habitat
Life cycle of an average star
nebula– protostar– average star– red giant– shell of gas– white dwarf
life cycle of a massive star
nebula– protostar– massive star–super red giant– supernova– neutron star
life cycle of a very massive star
nebula– protostar– massive star– red super giant– supernova– black hole
What is the Steady State Theory?
Everything has always existed and is currently expanding.
There is currently new matter being created.
Red Shift proves this
What is the Big Bang Theory?
Universe began from a tiny point with huge energy and has been expanding ever since.
All galaxies are moving apart so there must have been an explosion
Proven by Red Shift and CMB
What is CMB?
Cosmic Microwave Background Radiation
Microwave radiation is received from all parts of the universe and has the same temperature, suggesting that it all came from one place.
What is red shift?
Light from distance galaxies is being looked at and the frequencies have shifted towards the red end of the spectrum.
This suggests galaxies are moving away from us.
What is the Doppler Effect?
When a source moves towards an observer the wavelength decreases and the frequency increases.
When a source moves away from an observer the wavelength increases and the frequency decreases.
E.g. Ambulance has a high pitch ring when near you than when far away
