PV Gap

Jim Said:

how many planets are there in the solar system?

We Answered:

Currently there are 8 planets
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Pluto use to be a planet but they took it off the list this year. A set of strict guidelines are now used to identify a planet.
They are:
1. The object must be in orbit around the Sun.
2. The object must be massive enough to be a sphere by its own gravitational force.
3. It must have cleared the neighborhood around its orbit.

Pluto fails to meet the third condition
The guildlines were put in place by the International Astronomical Union (I.A.U.) in 2006

Irene Said:

How many planets are in our solar system and name them!?

We Answered:

"Uranus"...I have no idea, I just wanted to say that! ...good luck with your question!

Alvin Said:

How many planets are in the solar system in 2010?

We Answered:

Eight planets, plus two "minor" or AKA: "dwarf" planets (Ceres and Pluto).

Brad Said:

How many planets are in the solar system (as of 2007) and what are they?

We Answered:

Eight
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Neptune
Uranus

And - you could have looked this up on Wikipedia (although I appreciate the points)

Gabriel Said:

Why are inners planets in our Solar System rocky, but in many other solar systems the inner planet gas giants?

We Answered:

Before a newly-formed star reaches a stable equilibrium, it goes through a "T-Tauri" phase of producing an intense solar wind. (T-Tauri is named after the first star of this type discovered). In our solar system, this phase likely occurred while the planets were still forming from random debris. This would have pushed the lighter elements such as hydrogen and helium out of the inner solar system, leaving only heavier elements and rocks. The outer solar system was far enough from the sun for the solar winds to have no effect on the lighter elements, allowing them to form planets.

This theory seems to conflict with discoveries of extrasolar planets called "hot Jupiters". That is, large gas planets which are very close to their parent star. In this case it is theorized that they actually formed farther out, but orbital instabilities drew them closer over time.

Becky Said:

How many planets in the solar system are there?

We Answered:

There are eight planets in the Solar System. In order of increasing distance from the Sun, they are:
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
In order of decreasing mass, they are:
Jupiter
Saturn
Neptune
Uranus
Earth
Venus
Mars
Mercury

Pluto definitely still exists, just as it has existed for billions of years, it just isn't considered a planet now.

Jennifer Said:

Officially, how many planets in our solar system now?

We Answered:

When a NINE turns out to be EIGHT. It's not so great! It's not so great!

Sung to the tune of Jimmy Hendrix song.

A year or so ago, the people who find themselves in charge of determining just how many planets there are in the solar system determined that Pluto, now, is a captured planet. It didn't form with the rest of them. *shrug* They determined this by looking at its orbit. It's the most askew of the nine. Now, this COULD have been due to an impact a long time ago that set its orbit askew, and that must have been a HUGE rock that did that. Since Pluto resembles the moon to a great extent we should be able to see evidence of such an impact if it did happen.

Kind of funny if this is the case because you would think that such an occurrence would be reserved for a planet much bigger than Pluto, like Jupiter or Saturn, but who knows? Pluto, also, is the only terrestrial planet THAT far away from-the-sun. EVERYTHING else that far away is gaseous, save the asteroids. Maybe they used that clue to determine that Pluto, really, doesn't belong among the inner eight planets.