Its a sad day.. They say Pluto is no longer in the list Planets... In fact I should have got half a point more in my 8 class exam.. I was right then :)
For now, membership will be restricted to the eight (not nine, any more)"classical" planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Why the fuss.. has pluto changed? no, the rule has...
As a matter of fact, until recently there were no clear definition of a planet.. But now we have!
Hence Pluto is out with a googly and so the little cameo innings of more than 75 years is over..
The new rules for a planet: "a celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a ... nearly round shape, and has cleared the neighborhood around its orbit."
Instead, it will be reclassified in a new category of ex-planets or "dwarf planets" or in another astronomical term, a part of "Trans-Neptunian Objects" (TNOs). The number 1 item in TNOs.
After a tumultuous week of clashing over the essence of the cosmos, the International Astronomical Union stripped Pluto of the planetary status it has held since its discovery by Lowell Observatory astronomer Clyde W. Tombaugh in 1930.
...Astronomical Union stripped Pluto.. Where pluto will go now for justice.. how it will prove that it didnt head-butt anyone or took steroid.. :)
See the fate of NASA's New Horizons spacecraft.. It had started a journey of 9.5 years to the last planet.. but when it reaches there, its no longer a planet!!! It has to be seen if NASA decides to redirect it to the new last planet...
Interestingly, this is not the first time this has happened. The asteroid Ceres was a planet in the 1800s before it got demoted to the dwarf.
But on reflection, its a different feeling to know that the things which we believe fundamental may not be so tomorow.. Advances in technology made us believe that this was a planet and further advance showed us that it is not a plannet.. and what about tomorrow..
Referance & further reading:
http://www.cnn.com/2006/TECH/space/08/24/pluto.ap/index.html
http://www.freep.com/apps/pbcs.dll/article?AID=/20060825/NEWS05/608250411/-1/BUSINESS07
Footnote:
Thanks to the comment by Vinoo , I came to know about another twist that had happened. An initial proposal by the IAU was to increase the number from 9 to 12, with the additions of (1) earlier demoted Ceres, (2) the moon of Pluto, Charon and (3) the distant world known as 2003 UB313. But it ended up reducing one instead.. Thanks Vinoo..
More on this at..
http://news.bbc.co.uk/1/hi/sci/tech/5283956.stm