space physics Flashcards
(68 cards)
what is a satelite
anything that orbits a planet
what are the 2 types of satelites
natural-arent man made
artificial-are man made
what is an example of a natural satelite
moon
what is an example of artficial satelites
communication
orbiting telescopes
eg international space station
how many planets are they and what do they orbit
-8 planets
-orbit central star(the sun)
what are the 8 planets
mercury
mars
venus
jupiter
saturn
uranus
earth
neptune
how do all planets orbit the sun
in an elliptical orbit
what are asteroids
objects made of mostly rock and metal in the solar system
where asteroids mainly found
in the asteroid belt between mars and jupiter
what are comets
objects made of ice and dust that orbit elliptically
what are galaxies
collections of billions of stars(with their own solar systems)
what holds the stars together
force of gravity
what makes up the universe
trillions of scattered galaxies and empty space
what are star systems
central star orbitted by planets except ours which is called solar system
what galaxy is our system in
Milky way
what is a nebula
a big cloud of dust and gas
how is a protostar formed
a nebulas dust and gas is pulled together by gravity to form it
what 2 steps happens when as a protostar grows
-more particles collide and join protostar making it grow
-gravity gets stronger
step 3/4 of protostar growth
more gas and dust is attracted
and it is squeezed to become more dense
how does the temp of a protostar increase
as it densens particles collide more often raising temp/pressure
step 5 and 6 of protostar growth
hydrogen nuclei fuse to form helium nuclei by nuclear fusion releasing lots of energy making core hot
what happens after step 5/6 of protostar growth
it is now called a main sequence star or an actual star
why do main sequence stars last for billions of years
the inward pressure of gravity=outward of nuclear fusion resulting in a long stable period
what is an example of a main sequence star
sun