P5 Flashcards
how many planets are in our solar system?
8
what are the planets in our solar system, in order
mercury, venus, earth, mars, jupiter, saturn, uranus, neptune
what is an asteroid?
a small, rocky object that orbits a star
what is a satellite
any celestial object that orbits around a bigger one
what is a light-year
the distance travelled in the vacuum of space by light in one year
why do the planets orbit the sun?
the sun contains most of the mass in the solar system
where in the EM spectrum are the rays emitted by the sun
infrared, visible, ultraviolet
equation for orbital speed
v = 2πr / t
how does distance from sun affect orbital speed
- the strength of the suns gravitational field decreases as distance from the sun increases
- orbital speed decreases (bc less gravitational pull, centripetal force causing circular motion less)
how are stars powered
nuclear reactions that release energy. in stable stars, involve fusion of hydrogen into helium
what is the life cycle of a small mass star
- formed as protostar from interstellar clouds of gas and dust due to gravitational attraction
- red giant
- white dwarf + planetary nebula
what is the life cycle of a large mass star
- formed as protostar from interstellar clouds of gas and dust due to gravitational attraction
- red supergiant
- supernova
- neutron star
what is the life cycle of a very large mass star
- formed as a protostar from interstellar clouds of gas and dust due to gravitational attraction
- red supergiant
- supernova
- black hole
what can nebula from a supernova be used for
form new stars with orbiting planets
what are galaxies made of
many billions of stars
