 |
 |
| • HOME |
| • About Stockton, CA |
| • History of TWN |
| • kcuhC's Law |
| • kcuhCam: [All] 1 2 3 4 5 6 |
| • News & Info |
| • Discussion Forum |
| • Chat Room |
| • TRS-80 Information |
| • Cub Scout Pack 61 |
| • Adventures of Moooonica |
| • The Hague Family |
| • kcuhC's Site of the Weird |
| • Planetvest |
| • IKOP |
| • Hagueletts |
 |
Monday, September 06, 2010 |
|
||
|
||||
|
||||
| Welcome to kcuhC.com | The online home for The Wrong Number BBS | ||||
 |
The Solar System - 09/01/2006 6:30 AM On August 24, 2006, the International Astronomical Union (IAU) clarified the definition of the term “planet”. This redefinition resulted in the reduction of the number of planets in our solar system from nine to eight – Pluto lost “planet” status. It might seem odd that we needed to redefine a term that has been around for hundreds of years, but it really was necessary. Pluto was discovered in 1930, it was believed to be about the size of Earth, and was declared a planet. It didn’t take very long before we discovered a few interesting things about Pluto. Pluto turned out to be much smaller than originally thought – about the size of our moon. While most planets orbit in nearly perfect circles around the sun (eccentricity), Pluto has an elongated orbit that for about 20 years of its almost 230 year “year” bring it inside Neptune’s orbit! If you imagine the solar system as a flat pond, most of the planets are very close to orbiting on the surface of the water (inclination), however Pluto is tilted quite a bit so it spends a fair amount of it’s time well above the surface or below the surface of the water. Charon, Pluto’s moon was discovered in 1978. It is so large, compared to the planet it orbits that some have considered Pluto to be a “double planet”. Hydra and Nix are two much smaller moons of Pluto found in 2005.Very shortly after Pluto was discovered, debate began as to whether it should be called a Planet or not. It withstood all efforts to demote it…until today. The reason the issue was really brought to a head some 76 years after Pluto was original discovered is because of an exciting discovery in 2005. An object (unofficially called “Xenia”) larger than Pluto was found far outside of Pluto’s orbit (almost twice as far from the sun as Pluto). We know that there is a portion of the solar system called the “Kuiper Belt” that begins at about 30 AU and ends at about 50 AU (AU is an Astronomical Unit, or the distance from the Sun to the Earth, approximately 93 million miles). Pluto falls into this region of the solar system. As our technology has advanced we have found other objects in the Kuiper Belt. Mathematically we can anticipate that in the next hundred years we’ll discover hundreds or even thousands of objects that, “If Pluto is a planet, must also be a planet”. We, as an animal who likes to name and categorize things, need to decide if we want to live in a solar system overcrowded with planets. Let’s face it, we could memorize nine planets, but 3,847? Oops, there’s another, 3,838. Proposals have been made all over the place, tempers have flared, arguments and cases made. The IAU has taken the issue on, and finally made a decision. Their decision is basically this: A planet is an object that: 1) has enough mass (gravity) to form an essentially spherical shape; 2) Is the largest body in its “local group” (e.g., there is little or no debris in the orbital path, and what is there is significantly smaller than the main object); 3) Does not produce energy through nuclear reaction (is not a star). Another major proposal would have preserved Pluto as a planet and upgraded three other objects to planet status. This definition was interesting in that it too said the body had to be essentially spherical. It made no mention of being the largest in the “local group” and had an extra twist that elevated Pluto’s moon, Charon to a planet! If the Barycenter (center of gravity) is outside of any other body, the an object would be a planet. This is a little complicated, but imagine a teeter-totter. If two people are about the same weight, the center of gravity (Barycenter) is at the point between them. If you put a 50-pound child on one end, and a 200 pound person on the other, they can be balanced if you move the center point much closer to the larger adult. That center of gravity, so long as it is between the objects would qualify the objects at planets, not moons. If you consider the Earth, for example, the Moon does not, strictly speaking, orbit the Earth. The Earth and the Moon orbit each other. However because of the mass of the Earth and the distance between the Earth and the Moon, the center of gravity is about 25% between the outer edge of the earth and the center of the Earth. If the Earth was a basketball and the Moon a baseball, they would “orbit” around the point about three inches below the edge of the basketball. Because the “Barycenter” is “inside” the body that is the Earth, the Moon is a moon. But because, under this definition, Pluto and Charon’s Barycenter is in the space between the two objects, Charon would be considered another planet…Pluto and Charon would be a “double planet”. Another interesting note is that Earth’s moon used to be ten times closer to the Earth than it is today (imagine that full moon!) as it continues to move further away, it would, under this definition, eventually become a planet! Of course we won’t need to update our text books for another billion years or so, but… Another object that would become a planet is the yet to be officially named object commonly known as “Xenia”. The big shocker under this proposal was that Ceres, the largest asteroid in the asteroid belt between Mars and Jupiter would become a planet. Our solar system would have grown from nine to 12 planets under this proposal. Of course, over time we could have hundreds or even thousands of other “planets”. It has taken a long time to get to this point, but we are finally here…my rant. First, let me tell you what I think about our newly defined solar system, then I’ll tell you what I think SHOULD have happened. Demoting Pluto from planet status, stinks. About 5% of professional astronomers voted for this change. For 76 years we have all known of the nine planets. Even if we were to adopt this new definition, Pluto should have been “grandfathered in”. I strongly suspect that the “Pluto haters” will find an uprising that will eventually result in the reinstatement of planet status to Pluto – as it should be. This isn’t just a silly issue, it really isn’t. Here’s why… In practical terms, the value of astronomy and the space program is very low. While it has side-effects that are positive (new technologies) we have little direct benefit…over time we anticipate (and have recognized) value, but it is hard to say, “The ‘New Horizons’ probe launched to Pluto in 2006 will generate 11 billion dollars and cure cancer of the cuticle”. The Hubble space telescope helps to stir the imagination of “the common folk”. Hubble does good solid science, and it provides exciting eye-candy for Joe Six-pack. The arrogance of the astronomers who have voted for this change is shocking. Yes, defining an important term like “planet” is a good thing, but when you consider the common man’s understanding of the basics of Astronomy, why befuddle them? The demotion of Pluto will not please one vaguely interested common man. It will accomplish nothing constructive – it pleases the oversized egos of elitist astronomers who forget who really pays their salaries. The definition of “planet” should have been…
This means that our solar system would have:
The battle isn’t over…as of 09/01/2006, 300 professional astronomers have signed a simple petition that says: “We, as planetary scientists and astronomers, do not agree with the IAU’s definition of a planet, nor will we use it. A better definition is needed” Pluto, the ninth planet, is going nowhere. kcuhC, chuck@kcuhc.com |