22.1 Flashcards
Stars and planets form from what
nebulas
what consists in a nebula
hydrogen and helium with other elements and dust
is the collapse of a nebula slow or fast
slow
what causes the cloud to flatten
as the cloud spins the rotation slows at the collapse at the equatorial plane
stars form when
temp and pressure reach high enough levels for nuclear fusion to begin in the center of the rotating nebula
the what became the solar system
rotating disc around the sun
how did inner planets form
the elements that were closer to the sun and had a high melting point and formed the smaller rocky planets
how did the outer planets form
they were further from the sun and had a lower melting point
planetesimal
space object built of solid particles that can form planets through collisions and merges
how long is the diameter of a planetesimal
1K-100K+
How did planets form
small planetesimals kept colliding with one another
debris
material that remained after the formation of the planets and their moons
what was claudius ptomleys theory
thought the sun and the planets revolved the earth which was the center point
examples of debris that did not become part of a planet
comet meteors and asteroids
what was ptomleys theory called
geocentric model
retrograde motion
a planets apparent backward movement in the sky
could retrograde motion be explained with the geocentric model
no
what was nicolaus copernicus theory
his theory was that the sun was the center of the solar system
keplers first law
each planet orbits the sun in an elliptical shape
keplers second law
planets move faster when close to the sun and slower when farther away
keplers third law
the square of the orbital planet is proportional to the cube of the semi major axis of its orbit
astronomical unit
earths average distance from the sun
