P8 Space Flashcards
The ___ is orbited by the 8 planets and their moons and dwarf planets
Sun
What are the 8 planets in our solar system
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
What is the life cycle of a star that is a similar size to our sun
Nebula(dust particles attracted by gravity)
➡️Protonstar ➡️Main sequence (pressure from fusion balanced with gravitational pull)➡️Red giant➡️White dwarf(when fuel has run out)➡️Black dwarf(once cooled)
What is the life cycle of a star bugger than our sun
Nebula ➡️ Protomstar ➡️Main sequence➡️Red super giant ➡️supernova (when star is larger than our sun - produces heavy elements, and new nebula) ➡️ Black hole (so dense that gravity is so strong, not even light can escape)
What is a satellite
Any object that is in orbit of a planet
What is a geostationary satellite
A satellite that orbits the earth once every 24 hours
What are geostationary satellites used for
Communication
Geostationary satellites orbit above the same point in the ___
Equator
An example of a natural satellite
The moon
Monitoring satellites (weather) are lower and orbit ever - hours
2-3 hours
Satellites orbit around planets in _____ orbits
Circular (or slightly elliptical)
To find the distance travelled by a satellite we find the____ of the orbit
Circumference
Satellites can be ______ or ________
Natural(like the moon) or Artificial (weather or communication)
Why does velocity of a satellite change not not speed
Velocity is a vector, so when direction changes, so does velocity, however speed is not a vector so does not consider direction, so stays the same
If a satellite has an elliptical orbit it gets faster as it gets ______ __ _____
Closer to earth
What are the two pieces of evidence for the Big Bang
-Red shifted light from far away galaxies
-Cosmic microwave background radiation (CMBR)
What is the Doppler effect
When a siren (any noise) approaches you, it sounds higher pitched, but as it moves away it sounds lower pitched
What is red shift
The wavelength of light from the furthest away galaxies is increased (towards red) but the frequency is decreased
How is red shift evidence for the Big Bang
It shows that the universe is expanding
If a galaxy is moving towards ours, then the light from that galaxy is _____-_______
Blue-Shifted
What is blue shift
Wavelength of light is reduced, frequency is increased
What is CMBR
Cosmic Microwave Background Radiation
Why is CMBR proof of the Big Bang
A huge explosion would have created lots of energy in the form of gamma radiation. As the universe has expanded and cooled, its wavelength will have increased. This is CMBR, radiation left over from the Big Bang.
What makes up a nebula
Dust particles held together by gravity
When a star is formed it is stable because the forces within it are balanced. What forces?
Gravity (acting inwards) , balances with the outward force of RADIATION from NUCLEAR FUSION trying to star the star expand
When hydrogen runs out during fusion in a star, the force of fusion decreases and the star therefore contracts. This increases the ________ of the core until _______ starts fusing. This increases the radiative force and so the star expands to form a ___ ___
Temperature, Helium, Red Giant
