Topic 7 - Astronomy Flashcards
What was Greek astronomer, Ptolemy believe in astronomy?
He out the earth in the centre of everything with the planets and the Sun orbiting around it. GEOCENTRIC
However what was Nicolaus Copernius model?
A HELIOCENTRIC model with the sun a t the centre.
What are elliptical orbits?
Squashed circle orbits
What are natural satellites?
Anything that orbits a planet that has not been made by humans e.g moons
What are artificial satellites?
Something that orbits planets that humans have made I.e. NASA space station, communications e.t.c
What are the forces acting on a satellite ?
Gravitational force between the Earth and satellite is at a right angle to the direction of movement.
A satellite in a low orbit must be moving a lot fast than a high orbit because if it slows down, it will fall to Earth.
What is the life cycle of a star?
1) There is the Stellar Nebula
2) One way after , is the stable stage, when the Stellar nebula becomes a star, the same size as the sun.
3) Then it transforms into a dying star aka Red giant.
4) A planetary Nebula is then formed, and then a dense white dwarf and then a black drawf.
However after the nebula, it could of been turned into a massive star.
1) This then would have became a Red supergiant.
2)Then the Red supergiant explodes it’s layers becoming a supernova.
3) The supernova then transforms into a neutron star or a black hole.
A black holes are so dense that light can’t escape, and it warps space time.
A nebula is formed when protons and electrons are forced together to make neutrons
What is the Big Bang Theory?
The Big Bang theory is the theory that the universe was condensed into an infinitely small point.
Then after and or during the Big Bang, the universe rapidly expanded and cooled down.
This theory is supported by Red Shift and Cosmic Microwave Background Radiation
What is the steady state theory?
The steady state theory is the theory that the universe is expanding but new matter (galaxies and stars) were created.
This theory is supported by Red shift but breaks the conservation of mass theory.
What is Red Shift?
Red shirt is the observed increase in wavelength in the light from distant galaxies. The theory explains that distant stars and galaxies are moving away from us which must mean that they were originally together.
Red shifts support The BB and T SS
What is cosmic microwave background radiation? (CMBR)
CMBR is thought to be left over radiation for the Big Bang Theory. Therefore, CMBR supports TBB but now TSS
