PV Gap

Ross Said:

If all the asteroids in the solar system formed into a planet what size would the planet be?

We Answered:

Less than the Moon

http://en.wikipedia.org/wiki/Asteroid_be…

Tanya Said:

Which of the following statements best describes how the planets of the solar system formed?

We Answered:

B and C

The solar system formed as a flat nebula, with a gravitational centre becoming the sun, after initial formation the sun would have blown out more matter into the solar system, The lighter elements travelled further and became the gas planets, Jupiter, Saturn, Neptune and Uranus. whilst the heavier stopped closer to the sun, forming the inner four planets, Mercury, Venus, Earth and Mars. the initial rings of dust then coalesced over millions of years to form planets.

Glenn Said:

How was the Solar System Formed? Evidence?

We Answered:

Start out with an immense cloud of interstellar gas and dust left over from some ancient star that exploded and blasted its material into space.

Just like clouds in our atmosphere there was random currents and movements with this interstellar cloud. Also there were regions of higher density and it's there that gravity began gathering in the bits of gas and dust into clumps. As the clumps grew larger they pulled in more material.

One object within the cloud gathered more material than any of the others and so grew faster and larger than the others. Eventually it would become the sun. Because of its larger mass, the other smaller clumps began orbiting around this proto-sun.

Eventually the proto-sun turned into a real sun, and some of those other clumps took up stable orbits around it. Those would become the planets in our solar system. There's an excellent website with animated graphics to show this whole process =>http://ircamera.as.arizona.edu/NatSci1…

As for evidence that this is a valid theory, we just have to look into any existing cloud of gas and dust where we can actually see this solar system formation taking place. You can see just such a thing here =>http://www.sciencedaily.com/releases/2…

Justin Said:

After the Big Bang, how much time passed before the first solar system formed?

We Answered:

That's a really good question.

This is a question about metalicity. At the start of the universe there was just Hydrogen Helium and a bit of Lithium, anything else had to be made in stars, so in in the very early universe their might have been gas giants but no rocky planets, which I'm guessing you are after.

There is some indication of planets in globular clusters which are very old and would seem to indicate that planetary system can form quite early, but the answer isn't really known.

However if you said a billion years after the big bang, I don't think you would be too far out.

Roberta Said:

How did the solar system form?

We Answered:

The Sun and the solar system formed from the Solar nebula. As the nebula collapsed, most of the mass formed the Sun at its centre. The rest of the material formed the planets and asteroids and comets.

Lydia Said:

which of the following is not related to how the solar system formed?

We Answered:

Answer: D. The formation of the solar system has nothing to due with why objects orbit the sun in an ellipse. They do so because it is mathematically easier for an object to orbit in an ellipse rather than a circular orbit which would have to have all the forces on the orbiting object exactly balanced.