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Illinois Declares Pluto a Planet
The Bad Astronomer writes "The legislators in Illinois, always on the lookout for more places to find voters, have passed a resolution declaring Pluto is a planet. I'm not sure what else can be said here, except that — besides overstepping their jurisdiction just a wee bit — they make a couple of scientific howlers in the resolution itself."
Well it depends on how you define SUN
Our Sun is a star called Sol We call it the Sun because it is what we are in orbit around. If we were in orbit around an other star we would call that Star the Sun.
The more formal defination of a Planet is the following.
1. It Orbits around a Sun.
2. Its shape is Spherical
3. It is large enough to have or can attract and clear up other objects in its orbit.
#3 is the problem with Pluto with its orbit crossing Neptune once the time gets right and Neptune gets to close it will just Suck up Pluto and not the other way around. So even it Pluto was the size of the earth if it was where Pluto is now it wouldn't be considered a planet.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
In other news, a giant robotic Neil deGrasse Tyson was seen bursting through the walls of the Illinois Capitol Building, saying, "Pluto is a Plutoid. You have 30 seconds to comply."
"The IAU definition of a planet is more extensive than that."
A celestial body that is (a) 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.
Knowledge is power. Knowledge shared is power lost.
Nice selective quoting there. You missed a bit: "states that in the Solar System a planet is" .. so this definition doesn't apply outside the solar system, it doesn't say that things outwith the solar system cannot be planets.
Because Illinois is a northerly state... does Pluto ever actually pass "overhead"? Ever?
Yes.
Pluto's orbital inclination to the sun is about 11 degrees at maximum. The latitude of Illinois is much higher than that, at about 36 degrees. So Pluto may never pass through their air space, even if the borders of Illinois are extended upwards to infinity.
You are thinking about the inclination relative to the sun's equator - however, Pluto's orbital inclination to the Earth's plane is more than that: A bit over 17 degrees.
Earth's own axis is tilted 23.5 degrees, and as there's no obvious integer resonance between their orbital periods, Pluto will at some time be visible overhead at as
high as +/- ~40.5 degrees (17+23.5) - which is surprisingly close to Chicago's latitude of ~41 degrees. So either they got lucky, or someone actually thought about that.
However, Pluto right now is at 17.5 degrees south, so it will never be in zenith north of 6 degrees north (23.5-17.5) or - very roughly - Panama. And due to Pluto's loooooong orbital period of
about 250 Earth years, this will not change significantly for a very long time.
On an unrelated note: WhyTF is slashdot eating my degree signs - and not allowing the ampersand HTML entity?
Actually, that isn't as scary as you think. The biblical reference your making can logically be concluded to 3.14 and not 3 exactly.
In further news, the State of Illinois passes a law regulating the value of pi to exactly 3.000.
You realize that happened, right? Only it isn't 3.0, it's 3.2
Enigma