Solar system getting larger

[Ken King]

Wow the 10th planet, Sedna. How much will that cost to correct all the science books? http://www.cnn.com/2004/TECH/space/03/14/planet.discovery/

 

[Sharon]

I was reading about Sedna last night.

Here...
http://science.nasa.gov/headlines/y2004/16mar_sedna.htm

But a better link with more info is here...
http://www.gps.caltech.edu/~mbrown/sedna/

 

[Kain99]

I remember back when I home schooled the kids... We studied Planet X. Is this the same thing?

 

[huntr1]

Originally posted by Ken King
Wow the 10th planet, Sedna. How much will that cost to correct all the science books? http://www.cnn.com/2004/TECH/space/03/14/planet.discovery/

Originally posted by Sharon
I was reading about Sedna last night.

Here...
http://science.nasa.gov/headlines/y2004/16mar_sedna.htm

But a better link with more info is here...
http://www.gps.caltech.edu/~mbrown/sedna/

In other words, sharon just called you slow. Here's your .

 

[sleuth]

I noticed that one of the articles mentioned that it was still debatable as to what is considered a planet. So why wouldn't Quaour and Sedna be considered planets?

To me, if it is in the shape of an ellipsoid or spheroid, and it orbits a sun while not orbiting another planet, it ought to be considered a planet.

Anyone know what the current scientific definition of a planet is and why these two should or shouldn't qualify?

 

[Kain99]

I think the qualification issue is size. They have yet to determine a definitive set of standards.

 

[Toxick]

Originally posted by sleuth14
To me, if it is in the shape of an ellipsoid or spheroid, and it orbits a sun while not orbiting another planet, it ought to be considered a planet.

Well that covers comets, asteroids, and other assorted space debris and rocks.

Originally posted by sleuth14
Anyone know what the current scientific definition of a planet is and why these two should or shouldn't qualify?

I'm not sure, exactly, but I think that size is one of the determining factors (along with orbit eccentricity and maybe spheriod shape) and I know that Pluto just qualfiies as being a planet. In fact, there is much debate on whether Pluto is a planet or a body that escaped the Kuiper belt, but I think the scientific community gives it the nod, because it has its own satellite.

But since Pluto's status is questionable, based on size, then Quaour and Sedna - which are much smaller - should not even be on the debate table. Unless there are more criteria that I'm not aware of - which may well be the case.

 

[sleuth]

Originally posted by Toxick
Well that covers comets, asteroids, and other assorted space debris and rocks.

I thought comets were just irregularly shaped chunks of rock, as are astroids, space debris, and rocks.

Why hasn't some big fancy conference been held which says: "This is the definition of a planet: it has to be x feet in diameter, which an spheroidal or elliptoidal shape, orbiting a sun, have its own satellite, etc."

I wouldn't think it'd be that hard :shrug: Anything that meets the criteria is a planet. Anything that doesn't, isn't.

 

[Pete]

Originally posted by sleuth14
I thought comets were just irregularly shaped chunks of rock, as are astroids, space debris, and rocks.

Why hasn't some big fancy conference been held which says: "This is the definition of a planet: it has to be x feet in diameter, which an spheroidal or elliptoidal shape, orbiting a sun, have its own satellite, etc."

I wouldn't think it'd be that hard :shrug: Anything that meets the criteria is a planet. Anything that doesn't, isn't.

They are trying but the Uranusites and the Martians have permanent seats on the Planetary Counsel and have veto power. They keep vetoing the creation of a definition unless the FCC lets Howard Stern start farting on the air again.



I managed to lampoon Hward Stern and the UN in one post.......that is skill.

 

[Tonio]

Originally posted by Toxick
Well that covers comets, asteroids, and other assorted space debris and rocks.



I'm not sure, exactly, but I think that size is one of the determining factors (along with orbit eccentricity and maybe spheriod shape) and I know that Pluto just qualfiies as being a planet. In fact, there is much debate on whether Pluto is a planet or a body that escaped the Kuiper belt, but I think the scientific community gives it the nod, because it has its own satellite.

But since Pluto's status is questionable, based on size, then Quaour and Sedna - which are much smaller - should not even be on the debate table. Unless there are more criteria that I'm not aware of - which may well be the case.

I think you're right. Some astronomers believe that Pluto was originally a satellite of Neptune. Pluto's orbit isn't in the same plane as the others, meaning that the crew at Palomar doesn't look for it in the Zodiac constellations. I wonder how Pluto qualifies.

 

[SamSpade]

What's undecided is if it is a planet. There are many rocks out there orbiting the sun that are just big chunks of rock, and some of them have odd elliptical orbits that cross our own. Unlike the inner planets, Pluto and trans-Pluto discoveries appear to be captured rocks rather than planets which cooled and coalesced early in the formation of the solar system. There've been other discoveries of trans-Pluto type bodies, but no one has called them planets yet.