Formation of Solar System Flashcards
Formation of Solar System
- formed from nebula (cloud of gas and dust) approx. 4.6 billion years ago.
- nebula rotated and contracted under effect of its own gravity, flattening and getting thicker at core.
- planets began to appear in places where solid material formed balls.
- dust particles collided and coalesced into planetismals, which turned into proto-planets, which turned into terrestrial planets.
what are the terrestrial planets
mercury venus earth mars
what are the outer and inner parts of terrestrial planets made of
outer parts are rocky (silicates, organic matter)
inner core is metals (iron, nickel, aluminum, etc.)
density range of terrestrial planets
4-5.5 g/cm3
what are the giant/gaseous planets
jupiter and saturn
what elements are the gaseous planets mostly made of
hydrogen and helium
structure of gaseous planets
core is small and rocky but has metally H-H2 layers that gradually transition from fluid to gas
jupiter density
1.3 g/cm3
saturn density
0.7 g/cm3
what are the icy planets
uranus and neptune
what elements are the icy planets made of
mostly hydrogen and helium, but richer in carbon and nitrogen compared to gaseous planets.
icy planets structure
solid parts conist of ices of methane and nitrogen
uranus density
1.3 g/cm3
neptune density
1.6 g/cm3
3 ways of moon formation
accretion = same way planets form, applies to moons of big planets, small particles in protoplanetary disk come together with gravity, gradually builds up to moon.
capture = moon captured from asteroid belt or trojans by planet’s gravity, like mars’s moons.
impact = large object collides with planet causing debris to be ejected into orbit around planet and eventually coalescing into moon, often involved combination of first two ways, like our Moon.
