How many planets are there in the solar system now?
@chimex4real2k2 (1853)
Nigeria
9 responses
@hassei_takano (1411)
• Indonesia
30 Mar 07
Hmm.. I am still believe in 9 planet... I am still believe that pluto is still planet ^^
@nairdaleo (104)
• Mexico
31 Mar 07
Well yeah, it's what I was saying, we're just naming rocks by kind, there's an orbiting object on the solar system by the name of Pluto, be whatever it might be.
It's the same as if we were studying Venus and Saturn, they both have completely different properties regardless of how we classify them
@magnet (2087)
• United States
25 Feb 07
In the year 2005 three astromers, Michael Brown,Chadwick Trujillo, and David Rabinowitz discoverded the farthest thing yet seen in the solar system. It was three times bigger than Pluto. So they called it the Sun's tenth planet. It is a cold,icy planet that orbits the sun far beyond pluto. Also in 2005 astronomers found a moon going around the planet. The new planet is so far away that it takes 559 years to orbit the Sun. This period is more than twice as long as Pluto to orbit the Sun.
Some astronomers say that the new world is not really a planet. They even say that pluto is not a planet,either. In their view, both pluto and the new world are too small to be considered true planets. Both are smaller than Mercury. Instead, these astronomers say that Pluto and the new world are the largest members of the Edgeworth-Kuiper belt. If these people are right then there are only eight planets from Mercury to Neptune. There are many people that think that Pluto should be continue to be called a planet. That will mean that the new world will be a planet too because it is bigger than Pluto.According to these people,Pluto and the new world are planets and they are also the largest known objects in the Edgeworth-Kuiper belt.
@nairdaleo (104)
• Mexico
30 Mar 07
Well, the thing is not the size, but the orbit, and I think you forgot Uranus in your count! (no pun intended)
The Kuiper belt is like the asteroid field that orbits between Mars and Jupiter, only with cold asteroids made of the same stuff as Pluto. Pluto's orbit of course, isn't in the same plane as the other planets, but it orbits in the exact same way as the kuiper belt objects. That's why it is considered now not a planet.
The other planetS (yes, there are 3 more after pluto), do orbit the sun in the same plane as all the other planets, which makes them consider the possibility, but one other thing that is imperative for it to be a planet is that they ought to have an atmosphere, little as it might be.
Pluto has one, which is why for so long it was still considered a planet, although it's supposed to freeze and fall into Pluto's ground in about 10 years. The other "planets" after Pluto are too far to be seen with any of our methods with any precision, which is why we can't tell if they're planets or just asteroids floating for the sun's gravity.
@raijin (10345)
• Philippines
12 Jan 07
I think Pluto is now considered as a moon. I heard from someone, but not yet still sure if it's true. I have to take a search on this matter. Anyway, thanks for the info!;)
@chimex4real2k2 (1853)
• Nigeria
11 Jan 07
i also share the same view pluto has become too small a planet.
@sadgirl_1958 (1088)
• United States
7 Apr 07
Well according to the International Astronomical Union that met in August of 2006, Pluto is no longer listed as a planet, but is a "dwarf planet" giving us eight instead of nine planets in our solar system. However, proposals for other planets to join the ranks as a "solar system planet" is in the works and we could have as many as twelve in the coming years. It is a bit odd to lose Pluto as a planet considering we have been taught to believe there are nine planets in the solar system - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Who knows? In another few years we may need to memorize a few more.
@nairdaleo (104)
• Mexico
30 Mar 07
As usual, this is a problem of tradition.
Pluto has always been considered a planet for two reasons:
1. it's on the solar system orbiting the sun
2. it has an atmosphere
However it's orbit, although on the sun, belongs to the such called Kuiper belt, and also Pluto's general composition is the same as in the Kuiper belt objects, and to make matters worst, all Kuiper belt objects are frozen. Like Pluto.
But... there's still the problem of the atmosphere. However it is estimated that such an atmosphere will be falling down in about 10 years, so Pluto will have no choice but to "stop" being a planet.
But well think about it, we're just naming rocks that move in a certain way, it's not all that important as when you think of a rock made of Calcium and another one made of Magnesium
@jellybean80 (244)
•
11 Jan 07
I'd heard that it's now a dwarf planet, not entirely sure what the significance of that is though, so if anyone can enlighten me?...
@cvdrpepper53 (218)
• United States
16 Mar 07
i think theres 8 now since pluto made 9 and is now a dwarf planet
