Briefly outline the theory or hypothesis which best explains the ...

[fox]

Briefly outline the theory or hypothesis which best explains the origin of the solar system.
 
  What will be an ideal response?

Question 2

Why was Herschel's strategy for mapping our Galaxy flawed?
 
  A) His infrared telescopes couldn't penetrate the dust clouds.
  B) He used globular clusters, lying above the dust in the disc.
  C) He relied on visual wavelengths, which are obscured by dust.
  D) He used radio telescopes that didn't give enough resolution.
  E) He assumed Earth was at the extreme edge of the Galaxy.

[CharlieArnold]

Answer to Question 1

A large nebula began to collapse gravitationally. As it did so, it began to spin faster, and flattened into a disk. The disk heated up at the center, forming a protosun, and protoplanets began to accrete. Dust played an important role, both in helping radiate off excess heat, and in providing condensation nuclei for material to accrete onto. As protoplanets accreted, their gravity became significant and they became planetesimals. Planetesimals collided, forming planets. Leftover debris became asteroids and comets. Large planets far from the Sun (the jovian planets) underwent their own similar process, and became miniature solar systems.

Answer to Question 2

C