space Flashcards
(21 cards)
what is a planet
a rocky or gaseous body which orbits a central star
what is a moon
an object that orbits a planet or something else that is not a star
what is a star
a large ball of matter that is undergoing nuclear fusion and emitting light and other forms of electromagnetic radiation
what is a dwarf planet
an object that orbits a star but it is not large enough or roughly spherical enough to be classed as a small planet
what is an asteroid
an orbiting object which is even smaller than a dwarf planet. they are formed of rock and metals.
when an asteroid enters a planets atmosphere, we call it a meteor
what is a solar system
the solar system consists of the sun and everything that orbits or travels around the sun
what is an exoplanet
a planet existing around another star outside of our solar system
what is a galaxy
a large cluster of stars (eg the milkyway)
what is a universe
consists of many galaxies separated by empty space
what are uses of artifical satellites
-astronomical observations (hubble)
-communication ( satellite TV, telephones, internet)
-GPS
-Weather observation
geostationary satellites have a period of?
and an altitude of?
period- 24 hours
altitude- 36,000 km
how does the period of a satellite in a high altitude compare to a satellite in lower altitude?
it’s greater
challenges of space travel
huge distances involved, which either take very long times or require very high speeds
moving in zero friction conditions possibly to dock with the ISS
providing energy/food/water/life/communication for missions involving astronauts
where are geostationary satellites located
36000km above the earths equator
risks associated with manned space exploration
the pressure difference between spacecraft and the vacuum of space
high levels of radiation
extreme temperatures
risks of explosion at launch
risk of burning up on re entry to atmosphere
what is a light year?
the distance travelled at the speed of light in one year
how to convert one light year into a distance
d=vt
d= 3x10^8 x (60x60x24x365)
d= 9.46 x 10^15m
basic description of the Big Bang theory
Big Bang Theory- the idea that the entire universe once existed at a single point and has expanded over billions of years to form all the galaxies that we see today
estimated age of the universe
13.8 billion years
do satellites have a constant vertical acceleration
yes
what causes objects to heat up on re entry to earths atmosphere
force of friction is created on the objects surface which causes heat to be produced
