The mystery of Planet- or KBO- 'Mickey'
Here is a size-comparison of Planet 'Mickey' (aka 2003 EL61) with recently-discovered Kuiper Belt Object Sedna, Pluto, our own Moon, and Earth.
(NOTE: 'Mickey' is, of course, 2003 UB313, not 2003 EL61- the body to which the graphic refers. It was discovered the day before, and has been confused with the "new planet" ever since- though it, too, has a planetary claim, since it has a moon!)
I have absolutely no idea why the number 2003, rather than 2005, appears in 'Mickey's' temporary official designation (NOTE: Since composing this post, I have found out the reason. 2003 EL61 was actually discovered in 2003. Scientists have been holding off the official announcement until the body could be studied thoroughly enough to avoid the misinformation concerning its size and character which in fact accompanied the announcement of its discovery. However, word leaked, and so an official announcement was made now rather when when the body had been thoroughly-enough studied to satisfy the astronomers who discovered it).
I also haven't seen the word "planet" used about it in the media since the discovery that 'Mickey,' or 2003 EL61, is smaller than Pluto. (NOTE: 2003 EL61 is, indeed, smaller than Pluto. However, 'Mickey-' 2003 UB313- is indeed larger, as initially reported. This initial post on the discovery reflects a confusion between the two bodies on my part which mirrors what seems to be a similar confusion in at least some segments of the popular media and blogosphere).
It should be noted that there is no accepted definition for a planet; several moons in the Solar System are bigger than Pluto, including (as seen above) ours and the four Galilean moons of Jupiter (named after Galileo, their discoverer, and visible with a good pair of binoculars). Many astronomers want Pluto drummed out of the Planet Corps, arguing that it's just a large Kuiper Belt Object (essentially a rocky comet inhabiting a cloud of debris on the outer fringes of the Solar System, forced into its spherical shape by the laws of physics as a result of its comparatively large mass).
Some have recently suggested simply defining any globular object orbiting the Sun but no other primary as a planet, provided that it is of a certain, arbitrary size (say, 700-1,000 miles) be defined as a planet. In that case, our Solar System has not nine planets, but twelve or more.
Pluto appears safe for now. But 'Mickey's' status as a planet appears tenuous- though its discovery gives Sedna and the other candidates new credibility as potential planets. And aren't planets, after all, the only things that have moons, like 'Mickey's?'
Still no word on the name for Mickey discoverer Michael Brown of the California Institute of Technology has suggested to the International Astronomical Union.
Stay tuned for further developments.
(NOTE: 'Mickey' is, of course, 2003 UB313, not 2003 EL61- the body to which the graphic refers. It was discovered the day before, and has been confused with the "new planet" ever since- though it, too, has a planetary claim, since it has a moon!)
I have absolutely no idea why the number 2003, rather than 2005, appears in 'Mickey's' temporary official designation (NOTE: Since composing this post, I have found out the reason. 2003 EL61 was actually discovered in 2003. Scientists have been holding off the official announcement until the body could be studied thoroughly enough to avoid the misinformation concerning its size and character which in fact accompanied the announcement of its discovery. However, word leaked, and so an official announcement was made now rather when when the body had been thoroughly-enough studied to satisfy the astronomers who discovered it).
I also haven't seen the word "planet" used about it in the media since the discovery that 'Mickey,' or 2003 EL61, is smaller than Pluto. (NOTE: 2003 EL61 is, indeed, smaller than Pluto. However, 'Mickey-' 2003 UB313- is indeed larger, as initially reported. This initial post on the discovery reflects a confusion between the two bodies on my part which mirrors what seems to be a similar confusion in at least some segments of the popular media and blogosphere).
It should be noted that there is no accepted definition for a planet; several moons in the Solar System are bigger than Pluto, including (as seen above) ours and the four Galilean moons of Jupiter (named after Galileo, their discoverer, and visible with a good pair of binoculars). Many astronomers want Pluto drummed out of the Planet Corps, arguing that it's just a large Kuiper Belt Object (essentially a rocky comet inhabiting a cloud of debris on the outer fringes of the Solar System, forced into its spherical shape by the laws of physics as a result of its comparatively large mass).
Some have recently suggested simply defining any globular object orbiting the Sun but no other primary as a planet, provided that it is of a certain, arbitrary size (say, 700-1,000 miles) be defined as a planet. In that case, our Solar System has not nine planets, but twelve or more.
Pluto appears safe for now. But 'Mickey's' status as a planet appears tenuous- though its discovery gives Sedna and the other candidates new credibility as potential planets. And aren't planets, after all, the only things that have moons, like 'Mickey's?'
Still no word on the name for Mickey discoverer Michael Brown of the California Institute of Technology has suggested to the International Astronomical Union.
Stay tuned for further developments.
Comments
I get the Space.com updates, too. My most recent email from them says: New World Found! 2 Days Only: Save $5 off
That gave me a good chuckle! :)
It just struck me that if the IAU does decide to go with the 12 planet model, it would become "the world, Ceres!"
Cub fans, of course, wouldn't recognize the change.