THE ORIGIN OF THE SOLAR SYSTEM Flashcards
MODELS ON THE SOLAR SYSTEM
earth is the center of the solar system
geocentrism proposed by ptolemy & aristotle
MODELS ON THE SOLAR SYSTEM
sun is the center of the solar system
heliocentrism by nicolas corpus
THEORIES
about 5 ga, a rogue star passed close to the sun and stripped matetials (hot gases) from both the sun and the rogue star. the hot gases continued to spin in the same direction as the sun and coalesced into smaller lumps which formed planets
this theory was able to explain why all the planets revolve in the same direction and why the inner planets are denser than the outer planets.
however, the first problem with this theory is that even though hot gases expand, they would not contract, so how did the lumps of hot gas contract to form planets
encounter hypothesis
THEORIES
- proposed by immanuel kant and pierre simon laplace
- based on descartes ideas on pre-solar materials
- states that the entire solar system started as a large cloud of gas that contracted due to self-gravity
- hot central region became the sun
- materials surrounding it became the planets and other objects
objections:
- according to physics, the planets have higher angular momentum therefore bigger mass but in this case the proto sun has higher mass
- planets should be rotating far more slowly
- the sun should be spinning much more rapidly different rational velocities betweeen the inner and outer parts of a ring couldnt allow for condesation of material
nebular hypothesis
THEORIES
- present working model on the formation of the solar system
- built from nebular hypotheis
- cloud of gas and dust about 10 million km rotated slowly
- collapsed caused by either own gravity or explosion passing star, this reduces the size of the cloud resulting to increase in rotation
- gradually adding materials to increase its size
- interior became so hot it created hydrogen fusion, which formed the sun
- great plate-like disk surrounds the sun
- friction caused most of the mass to collect in a number of huge whirlpools, these shrank into more compact masses called protoplanets and later formed planets and moons
protoplanet hypothesis
THEORIES
- proposed by george louis leclerc and comte de buffon
- collision between sun and giant comet
- over 70,000 years
objections:
- earth’s age is too young
- comets are known to be far too smsall to have created the solar system in this way
buffon’s sun-comet encounter
what is the goldilocks zone or habitable zone?
- zone where life is possible
- temp. is not too hot or cold
