Space Physics Flashcards
What are satellites and what are the 2 types?
satellites are things that orbit an object and the two types are natural and artificial
what shape are the orbits of planets in our solar system?
elliptical
which two planets is the asteroid belt found between?
mars and jupiter
what is a comet mostly made out of?
ice and dust
what is an asteroid mostly made out of?
rock and metal
what is the life cycle of a star before it becomes a red (super) giant?
nebula
protostar
main sequence star
what is the rest of the life cycle for a small-medium main sequence star?
red giant
white dwarf
black dwarf
what is the rest of the life cycle for a large main sequence star?
red super giant
supernova (explosion)
neutron star
if star was extremely big, it becomes a black hole
what is the rest of the life cycle for our sun?
red giant
white dwarf
black dwarf
what is a nebula?
a big cloud of dust and gas
what is a protostar?
an accumulation of dust and gas, whose gravity attracts even more dust and gas making it bigger and denser.
What effect does the gravity of the protostar have on it?
attracts more matter making it bigger
squeezes the protostar making it denser meaning the particles collide more often causing the temperature to increase as well
what happens when the protostar gets hot enough?
nuclear fusion of hydrogen atoms to helium atoms starts taking place and the core of the star gets really hot, transitioning it into a main sequence star
at what stage is our sun currently in its life?
main sequence star
What happens during the main sequence star?
the outward pressure caused by nuclear fusion and the inward pressure by gravity is perfectly balanced allowing for long stable periods that can last for billions of years
eventually the star will start to run out of hydrogen meaning that gravity will be stronger and contracts the star into a hot dense ball until nuclear fusion can start up again.
this time the nuclear fusion will create elements all the way up to iron causing the star to expand again creating a red (super) giant
What happens in the red giant?
the red giant becomes unstable fairly quickly and expels its outer layers of dust and gas leaving behind a white dwarf
What is a white dwarf?
relatively small, hot, dense, solid core that does no fusion and gives off a lot of light. It eventually gets cooler and darker and transitions into a black dwarf
what happens in a red super giant?
they undergo more fusion and become brighter. after several cycles of expansions and contraction they eventually explode into a supernova
what happens in a supernova?
forms element heavier than iron that get ejected across the universe. if the star was pretty big, it condenses into a neutron star which is a very dense core. if it was absolutely massive, it would collapse in on itself and become a black hole
what atoms fuse together in a main sequence star?
hydrogen atoms to make helium
what atoms fuse together in a red (super) giant?
all atoms to form elements up to iron
what atoms fuse together in a supernova?
elements heavier than iron
what is the difference in speed and velocity of an object in orbit and why?
speed is constant, velocity is always changing because the object is always changing direction
is an object in orbit accelerating or staying at a constant velocity?
it is constantly accelerating as the velocity is constantly changing
what is the relationship between the size of an object’s orbit and its speed?
the smaller the objects orbit, the faster it’s is going to have to go to prevent being sucked in.
what 2 forces create an orbit?
An objects instantaneous velocity and the gravitational pull
what is red shift?
the stretching of light rays as they move due to the emitter moving away.
which galaxies will move away from us the fastest?
the most distant ones
what is the big bang theory?
all the matter in the universe was in a hot dense spot called a singularity. The singularity exploded and expanded which is still continuing to this day
What does CMBR stand for?
cosmic microwave background radiation
What is CMBR?
electromagnetic radiation observed in all direction. Initially radiation from big bang was very hot, as the universe expanded and cooled the background radiation dropped in frequency
What is the redshift equation?
change in wavelength / original wavelength = recessional velocity / speed of light
what provides evidence for the big bang?
red shift
why are galaxies moving away from each other?
Space and the universe itself is expanding and this makes galaxies further apart
roughly how long ago was the big bang?
13.8 billion years
