
Pluto with its largest moon, Charon, is now a dwarf planet
Pluto is named after an underworld god, and that thing however you want to call it has been a topic of intense debate. I wonder if it has anything to do with its name? Who’s gonna determine an underworld god’s fate? Life after death? 
A fierce backlash has begun against the decision by astronomers to strip Pluto of its status as a planet.
On Thursday, experts approved a definition of a planet that demoted Pluto to a lesser category of object.
But the lead scientist on Nasa’s robotic mission to Pluto has lambasted the ruling, calling it “embarrassing”.
And the chair of the committee set up to oversee agreement on a definition implied that the vote had effectively been “hijacked”.
The vote took place at the International Astronomical Union’s (IAU) 10-day General Assembly in Prague. The IAU has been the official naming body for astronomy since 1919.
Only 424 astronomers who remained in Prague for the last day of the meeting took part.
Ok 424 astronomers showed up in the voting, but how many were supposed to be there initially???
Did people give up their votes and why?
Dr Alan Stern, who leads the US space agency’s New Horizons mission to Pluto and did not vote in Prague, told BBC News: “It’s an awful definition; it’s sloppy science and it would never pass peer review - for two reasons.
“Firstly, it is impossible and contrived to put a dividing line between dwarf planets and planets. It’s as if we declared people not people for some arbitrary reason, like ‘they tend to live in groups’.
“Secondly, the actual definition is even worse, because it’s inconsistent.”
One of the three criteria for planethood states that a planet must have “cleared the neighbourhood around its orbit”. The largest objects in the Solar System will either aggregate material in their path or fling it out of the way with a gravitational swipe.
Pluto was disqualified because its highly elliptical orbit overlaps with that of Neptune.
But Dr Stern pointed out that Earth, Mars, Jupiter and Neptune have also not fully cleared their orbital zones. Earth orbits with 10,000 near-Earth asteroids. Jupiter, meanwhile, is accompanied by 100,000 Trojan asteroids on its orbital path.
This is like an action-reaction dilemma, some readers pointed out. If Pluto is disqualified, Neptune should be disqualified as well, no? Who is bumping into who, anyway???
Relative perspectives. 
E-voting
Professor Gingerich, who had to return home to the US and therefore could not vote himself, said he would like to see electronic ballots introduced in future.
Alan Stern agreed: “I was not allowed to vote because I was not in a room in Prague on Thursday 24th. Of 10,000 astronomers, 4% were in that room - you can’t even claim consensus.
Read more on: bbc.co.uk
Ok, so…only 4% of astronomers in that room on August 24, 2006. Now people are considering electronic vote, so that everyone will have a chance to say.
Well, why not just wait until the satellite probe reaches Pluto in year 2015 and then decide again? Definitions are man-made. They can be challenged and changed at any time as our knowledge grow further.