2006-11-08 14:04:19 · 23 answers · asked by Tinka 1 in Science & Mathematics ➔ Astronomy & Space
Pluto.
The International Astronomical Union (IAU), at a meeting in August 2006, voted on their first "official" definition of a planet. Based on this new definition, Pluto is no longer a planet. According to the IAU's definition, our Solar System has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. In the new scheme, Pluto will be one of several "dwarf planets" in the Solar System; but "dwarf planets" are not considered true planets. THere is still a lot of disagreement within the community on the definition of a planet.
Here's the definition of a planet (found at wikipedia):
The International Astronomical Union defines "planet" as a celestial body that, within the Solar System,
(a) is in orbit around the Sun;
(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape; and
(c) has cleared the neighbourhood around its orbit;
or within another system,
(Pluto fails to meet the third condition above)
(i) is in orbit around a star or stellar remnants;
(ii) has a mass below the limiting mass for thermonuclear fusion of deuterium; and
(iii) is above the minimum mass/size requirement for planetary status in the Solar System.
2006-11-08 14:05:53 · answer #1 · answered by ami 4 · 2⤊ 0⤋
Pluto
2006-11-08 15:38:54 · answer #2 · answered by G/M P 1 · 0⤊ 0⤋
Pluto
2006-11-08 14:11:45 · answer #3 · answered by sanman2234 2 · 0⤊ 0⤋
Pluto
2006-11-09 16:51:14 · answer #4 · answered by Syd 2 · 0⤊ 0⤋
Poor Pluto
2006-11-08 14:11:47 · answer #5 · answered by Zoey 5 · 0⤊ 0⤋
Pluto
2006-11-08 14:06:05 · answer #6 · answered by I know, I know!!!! 6 · 1⤊ 0⤋
Pluto
2006-11-08 14:04:52 · answer #7 · answered by Anonymous · 1⤊ 0⤋
Pluto and is now considered a dwarf planet
Pluto Diameter: 2390 km, 0.2 Earth Diameters
Planetary Mass: 1.25x1022 kg, 0.0025 Earth masses
Average Distance from Sun: 5.913 billion km, 39.53 AU (astronomical units)
Length of Day: about 6.4 Earth Days
Length of Year: 248.53 Earth Years
Day/Night Surface Temperature: 54-59 degrees Kelvin
Number of natural satellites: 1 - Charon
Planetary ring system: No
Average temperature: ~50 K (-223 C)
Atmospheric composition: Methane (CH4), Nitrogen (N2)
2006-11-08 14:10:29 · answer #8 · answered by Anonymous · 0⤊ 0⤋
PLUTO finally. It is now called a dwarf planet. This was mainly because they found many other objects beyond Pluto that were much bigger than Pluto. It is not a amin planet. But we'll always call it one.
2006-11-09 02:58:32 · answer #9 · answered by AHHH CHOOOOOOOO (sneeze)! 2 · 0⤊ 0⤋
that would ave to be pluto as it is now classed to small to be an actual planet
2006-11-08 14:12:46 · answer #10 · answered by Anonymous · 0⤊ 0⤋