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mario
2004-Mar-16, 07:38 PM
What with all the debate over Sedna and Pluto, and what constitutes a planet, I gotta wonder if anything can qualify as a planet at all? The origin of the word comes from the Greek planasthai, which means "to wander", because the planets (including the Sun and Moon) appeared to wander around a motionless Earth and motionless stars. But now we know better, and this definition of a planet as a "thing that moves around in the sky" is insufficient, since I'm pretty sure that most things in the Universe tend to move around now and then.

So I say, enough with it. Nothing is a planet in the original sense of the word. It's high time we come up with a new labeling system that makes sense.

Ut
2004-Mar-16, 07:53 PM
Well, that's an intersting voting pattern.

The third option's a red herring. No one will argue that we don't know enough about Earth. The planetary sciences deserve more respect.

nebularain
2004-Mar-16, 08:13 PM
Actually, Mario, you have a good point. We started labling things before we actually understood what they were or how they operated. New labling system - sounds good to me!

kucharek
2004-Mar-16, 08:17 PM
In the classic sense, Earth isn't a planet. I never saw it wandering in the skies...
Dropping "planet" and establish a new system? We will have married, female popes before this happens.

Harald

Andromeda321
2004-Mar-16, 10:20 PM
I say anything that isn't a ball of gas that didn't become massive enough to trigger fusion isn't a planet. So hence Earth, along with Mercury, Venus, Mars, and Pluto, are only "planetoids." 8)

JohnOwens
2004-Mar-16, 11:13 PM
The third option's a red herring. No one will argue that we don't know enough about Earth. The planetary sciences deserve more respect.

What makes you so sure those are planetary sciences??


Dropping "planet" and establish a new system? We will have married, female popes before this happens.

Married to another woman, or just married to a man?

Glom
2004-Mar-16, 11:19 PM
I still fancy the idea of defining a planet in this solar system as one that is the significantly dominant mass in a low eccentricity, low inclination orbit that follows Titius-Bode sequence of planetary orbits.

Amadeus
2004-Mar-16, 11:26 PM
Excuse me for being simple but.....

I always defined it as

Planet = Body that orbits a star (yes I know theres stuff like comets that also orbit the Sun but..... look just agree with me here I'am trying to make it easy for the kids. We can mess with their heads when they paid the college dues and it's too late for them to back out. Look ok if it makes you happy we'll set a minimum size for a body that can be classed as a planet or a moon. How big? *sigh you had to be awkward didn't you. Couldn't let it be. O.K how about 2000km accross? Happy now?)

Moon = Body that orbits a planet as defined above

:lol:

semi-sentient
2004-Mar-16, 11:43 PM
Where's the "Earth is a comet" option???

milli360
2004-Mar-17, 12:10 AM
I still fancy the idea of defining a planet in this solar system as one that is the significantly dominant mass in a low eccentricity, low inclination orbit that follows Titius-Bode sequence of planetary orbits.
How low eccentricity? Would you accept a planet whose minor axis was 1% less than its major axis? 3%? 5%? 10%?

Manchurian Taikonaut
2004-Mar-17, 12:22 AM
Venus, Mars and Earth are inferior-Planets...maybe the Earth-Moon is a double planet system?

Jupiter, Neptune, Saturn, Uranus are superior-Planets

But what are...... Mercury? Titan? Ganymede? Pluto? Europa? Sedna? Triton?

Ut
2004-Mar-17, 12:31 AM
But what are...... Mercury? Titan? Ganymede? Pluto? Europa? Sedna? Triton?

Planet, moon, moon, disputed, disputed, moon.
The one thing that's pretty universal in the definition of a planet is that it must orbit the/a sun. Orbiting a planet makes it a moon.

I agree with KK & Swift in the Pluto thread. Pluto's a planet under a grandfather clause. Sedna, however, is inclined on two axis to the ecliptic. Maybe I'm a planetary biggot, but that bothers me.

Manchurian Taikonaut
2004-Mar-17, 12:42 AM
Yes, I think pluto should remain our ninth planet!


but some have said Pluto, Mercury and Sedna could be classed the same as Ceres and Vesta

Kaptain K
2004-Mar-17, 12:43 AM
...Earth isn't a planet. I never saw it wandering in the skies...
You've never used psychodelics, have you? :oops: :wink: 8)

Wiley
2004-Mar-17, 12:47 AM
I had to vote for option 3. In fact, this whole thread, and any thread on this alleged Earth, should be moved to "Against the Mainstream".

The Watcher
2004-Mar-17, 12:55 AM
Well I can't believe I'm the first one to mention this.

Perhaps we can use the method they use on a little known TV show called 'Star Trek'.
As I'm sure you all know they called planets by the number of that planet out from the star it's orbiting. For example. "Thie signals coming from Diniva 4 Captain" or "It looks like our final resting place will be Kerfuffle 2, unless ...Data?"

Therefore earth should be renamed SOL 3

And likewise Mars becomes SOL 4 and Satrurn SOL 6.

"My God captain, there are remains of intelligent life on a moon orbiting SOL 3."
"What about the SOL 3 itself?"
"Nope, just bunch crazy beings typing into there electroninc consols all day"
"Okay, lets leave them to it for another 1000 of there SOL 3 years..."

Brady Yoon
2004-Mar-17, 04:30 AM
I don't think calling anything a planet is valid. Then we would have to call all objects even space dust, planets...

mario
2004-Mar-17, 08:07 AM
I had to vote for option 3. In fact, this whole thread, and any thread on this alleged Earth, should be moved to "Against the Mainstream".

Anyone seen the latest Earth rover photos?

http://www.woodsonginc.com/concerts/images/Festival2001/Bunnies.jpg

Hoagland's gonna have a field day with this one.

Chip
2004-Mar-17, 08:38 AM
...Anyone seen the latest Earth rover photos?

I see three pieces torn off from the airbags of the Martian Space Agency's lander when it bounced in. They kind of resemble the Martian bunnies, but they’re too big. Earth sure is a strange place. :wink:

Swift
2004-Mar-17, 01:56 PM
Venus, Mars and Earth are inferior-Planets...maybe the Earth-Moon is a double planet system?

Jupiter, Neptune, Saturn, Uranus are superior-Planets

But what are...... Mercury? Titan? Ganymede? Pluto? Europa? Sedna? Triton?
Hey, you don't have go judging which planets are better than the others! Just because the first four are small you don't have to go calling them inferior. [-X They are not inferior, they are just differently enabled planets!

Amadeus
2004-Mar-18, 12:03 AM
I had to vote for option 3. In fact, this whole thread, and any thread on this alleged Earth, should be moved to "Against the Mainstream".

Anyone seen the latest Earth rover photos?

http://www.woodsonginc.com/concerts/images/Festival2001/Bunnies.jpg

Hoagland's gonna have a field day with this one.

There are any maner of problems with this photo. First off it's not true colour and this just is a bit of disinfo. Whilst the "bunnies" look raised there are in fact holes in the ground. this is caused by seeing light come from the bottom of the photo. Lastly everybody knows that there is too much oxygen in Earths atmosphere for complex life to exist.

:D

All hail Mr.Bunny! Ruler of Mars.

tracer
2004-Mar-18, 06:30 AM
Re: Earth: Planet or Not?

Of course not. Earth is just a Kuiper belt object.

umop ap!sdn
2004-Mar-18, 06:57 AM
I still fancy the idea of defining a planet in this solar system as one that is the significantly dominant mass in a low eccentricity, low inclination orbit that follows Titius-Bode sequence of planetary orbits.

But then you'd have to exclude Neptune because its semi-major axis breaks the pattern. Pluto is where Neptune should be and therefore it ironically would be a planet. :-?

tracer
2004-Mar-18, 07:10 AM
(Except for the whole "low eccentricity, low inclination orbit" thing.)