Could the Nemesis and/or Planet X hypotheses be correct?

[Hypercube]

I was reading about the theories of a tenth planet or even a companion star for the Sun existing somewhere out in the Oort Cloud. And I was just wondering whether or not they could actually exist. I mean I guess that a tenth planet isn't so farfetched (or at least not impossible) when you consider that there are supposed to be trillions of objects in the Kuiper Belt and Oort Cloud.

[Fanghur]

Well, I suppose it's not impossible that there could be a tenth planet somewhere beyond the orbit of Pluto, since as Hypercube said, there is certainly enough material out there for a planet to form. As for the Nemesis theory, I think it's highly unlikely, although I suppose that if the companion star was small and dim enough it's possible that it would be hidden by the Oort cloud. Neither theory is impossible, but the Nemesis theory is very improbable.

[iNow]

Don't we only have 8 planets now anyway (+1`planetessimal)?

[Fanghur]

iNow as far as I'm concerned, Pluto will always be the ninth planet.

[Hypercube]

I agree, I think it was stupid to demote Pluto, but I did not start this thread to debate NASA's stupidity.

[antimatter]

I haven't heard much about either of these theories, but there's no real way of knowing, unless we send out some sort of probe to check it out. Although I'm sure Ironman could do the job.

 

Thanks to the geniuses at NASA, all the models and posters and videos in science classes have to be trashed.

Way to go, NASA!

[Klaynos]

There are larger objects further out than pluto in similar orbits to pluto, they're hard to see, we're likely to see more, which is one of the main reasons why pluto is no longer considered a planet.

 

As for another star, no it'd be VERY bright...

[Joegocal]

I agree, I think it was stupid to demote Pluto, but I did not start this thread to debate NASA's stupidity.

 

NASA didnt actualy do that was the IUA but thats besides the point. in order to not have to classify Ceres and Eris the dwarf planets as acctual planets. the IUA decided to redefine planet and in doing so had to kick pluto out. imagine what an uproar it would have been to have to more plantets instead of just losing one.

[Hypercube]

I'm not debating that Pluto might be too small to be considered an actual planet, what makes it stupid to demote Pluto is the fact that every astronomy book ever written calls Pluto the ninth planet, not to mention the fact that everyone has heard of Pluto, whereas Ceres and Eris are virtually unknown to most people. Besides, Pluto has a moon, and a very thin atmosphere (at least I think it does). The point is that Pluto has always been known as the ninth planet, and I think it should still be, if for no other reason than to keep all of the books accurate.

[Fanghur]

I agree with Hypercube, size isn't everything. I've often wondered if it might be possible to consider Titan as a kind of planet orbiting a planet. After all, it is larger than Mercury, has a very thick atmosphere, oceans on its surface (albeit ones you wouldn't want to go swimming in, although there must be some pretty big waves considering Saturn's gravity), it's rich in organic materials, and hey who knows, maybe it even has some kind of ammonia based lifeforms (I'm just saying, who knows?). Maybe Titan was a planet at some point but got captured by Saturn's gravity, since there is no question that if Titan were orbiting the Sun rather than Saturn, it would certainly be considered a planet.

[gonelli]

The point is that Pluto has always been known as the ninth planet, and I think it should still be, if for no other reason than to keep all of the books accurate.

 

If you wanted to keep books of science accurate, then we should all be still believing that the world is flat.

[Hypercube]

If you wanted to keep books of science accurate, then we should all be still believing that the world is flat.

 

No offense Gonelli, but that statement is one of the most ridiculous analogies I've ever heard in my life. It's a huge leap to compare people thinking the earth is flat a few thousand years ago, which we now know has absolutely no scientific credence whatsoever, to calling pluto a planet. Especially since unlike the "flat-earth" hypothesis, pluto fits the definition of a planet almost perfectly; it orbits the Sun, it has a moon, it has an atmosphere (albeit a very thin one), it is sufficiently large to allow gravity to mold it into a sphere, etc.

 

I understand that since they have found objects larger than pluto out in the kuiper Belt that it was probably inevitable that pluto would eventually be demoted, but I still think that it was a stupid to do.

[iNow]

Especially since unlike the "flat-earth" hypothesis, pluto fits the definition of a planet almost perfectly;

But actually, it doesn't, which is precisely why it was demoted.

[Klaynos]

I don't think it really matters much if you call Pluto a planet or not...

 

But for note, Eris also has a moon, it's bigger than pluto, so probably a thicker atmosphere, and orbits the sun...

 

Ceres is ALOT closer to the sun...

 

There is fundemental formation difference between a planet and a dwarf planet and that is the ability to clear the region of planetesimals... without that having been achieve it's not a planet...

[BumFluff]

I'm not debating that Pluto might be too small to be considered an actual planet, what makes it stupid to demote Pluto is the fact that every astronomy book ever written calls Pluto the ninth planet, not to mention the fact that everyone has heard of Pluto, whereas Ceres and Eris are virtually unknown to most people. Besides, Pluto has a moon, and a very thin atmosphere (at least I think it does). The point is that Pluto has always been known as the ninth planet, and I think it should still be, if for no other reason than to keep all of the books accurate.

 

Ceres was once known as a planet before they discovered that there was an asteroid belt. If we go by what you say Pluto should actually be the tenth planet and whatever planet this thread mentions should be the twelfth planet. Or maybe the thirteenth or fourteenth.

[Kiddy]

Well, as far as we go, Pluto is no longer a planet or a dwarf planet, today is a plutoid, which is an dwarf icy planet beyod the orbit of Neptune. That will make Eris a plutoid as well, but I´m not sure if Eris is icy as well. So, seems we don´t have something that we could call a tenth planet...

Anyway, I would not be thinking about printing new astronomy books for the next five years at least.