2 new moons found Orbiting Pluto

www.space.com...

Quite amazing that such a small "planet" can have so many satellites. And they thought that these 2 moons were formed together with their bigger brother Charon in a collision.

There are still so many mysteries surrounding Pluto after it was discovered 75 years ago. Luckily New Horizons is going to solve them, but not until 2020.

Another surprise Hubble has brought us. Sad to see it go...


[edit on 31-10-2005 by NotheRaGe]

Does anyone have any ideas on why this is ??

[edit on 1-11-2005 by SHHCAGO]

Personally, I've never considered Pluto a planet. It's orbit and diameter make it almost assuridly a Kuiper belt object. Most likely a very large captured comet from the outer Oort cloud.

As far as why it has moons? No real supprise. It takes Pluto close to 200 years to make one rotation around the sun. At such a slow velocity, gravity can overcome escape velocity.

Pluto at one time was probably an ice ball about 1 1/2 times it's current size. An impactor is the most probable cause of the formation of Charon and the ancillary moons.

I have no doubt that there are much larger bodies in the Kuiper belt and the Oort cloud. Just a matter of time to find them...

[edit on 11-1-2005 by wetwarez]

[edit on 11-1-2005 by wetwarez]

[edit on 11-1-2005 by wetwarez]

Pluto may be a KBO but it is a darn big one, even possibly be a double planet. Stadns to reason thave enentually something that big is going to capture other KBOs

Any of the Gas Giants could be concidered thier own soalr systems to.

Really what it boils down to is what should be conidered a planet. Maybe base it on size and density

I somewhat agree though if we were to describe a planet based on density, would you consider Saturn a planet? It's density is less that water. If there were a large enough body of water, Saturn would float.

So, do we use rocky planets as a basis? If so, count out the gas giants. But, if we do it that way, what's the lower end limit? Pluto is only 1 1/2 times larger that the moon. How do we classify a Planet?

I have a feeling this debate will rage on for years. Though I personally would stop counting plantes after Neptune.

your thinking too litteral. Size first, and then if it smaller then lets say mars (Or a given diameter smaller), it has to have a certain mass, or density. That way Gas planets are never questioned as being planets

The grey area is KBO and large moons or asteroids. Size then density could solve that since planets would have to be mostly rock, and not rock/ice or Ice

I thought such multibody systems were unstable. Pretty weird.

Ok, I'm very literal minded... sorry, habbit. Anyway lets use distance (AU) and density/mass. That might be a more acceptable measure of "planethood". Let's use the demarkation line of Pluto's orbit and say anything inside this line is a planet, anything outside is a KBO or Oort cloud object.

Any of the ways we do it, is arbitrary. Again, this will be debated for years to come.

Basically, IMHO I would say that anything clearly orbiting a star (or stars as the case may be) should be considered a planet because whether or not it was captured or formed at the start of the universe its still orbiting the sun and will otherwise work as a planet. Phobos and Deimos are Mars's moons, and though they are clearly captured asteroids we still considered moons. The sun captured a comet or asteroid from somewhere, so why can't we call it a planet?

I don't agree. With that line of reasoning, the asteroid belt between Mars and Jupiter isn't just rubble but thousands of tiny planets?

I find this a hard argument to follow. But see your logic as far as a definition is concerned.