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New Tenth Planet Has a Moon
starexplorer writes "SPACE.com is reporting that the recently discovered 10th planet of our solar system has a neighbor - a moon. The discovery team also have nicknamed the planet 'Xena' and the moon 'Gabrielle'. Many scientists are objecting to whether the new planet really is a new planet - so what do you call a moon with no planet?"
Artificial satellites are not usually described as "bodies," now, are they?
Probably, we need to have a lot more terminology to describe satellites orbiting other objects. The terms "irregular moon", "regular moon" and "outcast moon" already exist. There are satellites of moons and also binary systems where objects sort of orbit each other. It will probably be another decade before concensus develops on all this.
Or a captured asteroid.
Tequila: It's not just for breakfast anymore!
Since we already classify the rocky planets and the gas giants together, there is absolutely no reason not to combine the third group of large (read gravitationally spherical) objects. For those of you who insist on a degree of perfectness, show it to a kid. If he says it's a round ball, then quit griping about it.
Incedentally, moons should be gravitationally spherical, too. I hate the way scientist are still discovering rocks the size of my house and calling them moons of Jupiter or Saturn. Yes, this would reclassify Phobos and Diemos to mere satellites. Alternatively, a moon could be an object that doesn't look like a star from the surface of the host planet. Kinda hard to nail that down for the gas giants, though.
Just out of curiousity, someone up the thread mentioned moons with moons of their own. Can you post a reference on that?
Always going forward, 'cause we can't find reverse.
"Moon" means the same as "satellite," which both mean "object that orbits a planet." That waning crescent in the sky is a natural satellite. Hubble is an artificial moon.
Something that doesn't orbit a planet is neither a moon nor a satellite. If it orbits the sun and is of reasonable size, you can call it a "planet," or maybe "planetoid."
We don't call Voyager or Pioneer "satellites" for a reason.
A contributor to Wikipedia, by the way, has amusingly recognised this and posted the following definition (and no, it wasn't me, my Latin is not nearly good enough)
Satelles dicitur corpus caeleste naturale quod circum planetam vel asteroidam revolvitur et ipsum non lucet
(S?)he defines it as a natural body which revolves around a planet or an asteroid. I disagree with the "natural", but at least I'm not alone in the world on this!
Panurge has posted for the last time. Thanks for the positive moderations.
Michael Brown, one of the scientists on the team that discovered the planet and now its moon, has an excellent website about 2003UB313 and has been keeping it current. I've been checking it out to see if there are any interesting developments about the team that apparently claimed the discovery of 2003UB313 without mentioning the fact that they at least visited the logs of the telescope Brown's team was using, if not outright deducing its existence from those logs. It's great to see this kind of rapid dissemination from the principals. By the way, he also has an extensive website about his newborn daughter's sleep patterns which is pretty impressive too...
It's psychosomatic. You need a lobotomy. I'll get a saw.
I think Herman Melville gets to claim priority even over Battlestar Galactica, let alone the burnt coffee chain. He used Starbuck as a character in a book (Moby Dick) over 150 years ago.
-- Alastair
Ida And Dactyl
Ida Is an Asteroid. Dactyl is another asteroid which is a moon of Ida. I dont see anyone calling Ida a planet just because it has a moon.
All misspellings and grammatical errors in the above post are intentional and part of my artistic expression.
I thought they had already found the "10th" planet. Wasn't it called Sedna? And what ever happened to that other object that had a moon they found called EL61? Here is a reference to the story: http://www.msnbc.msn.com/id/8756128/
How many tenth planets does our system have? I thought that in 2003, it was already named Sedna. (http://www.gps.caltech.edu/~mbrown/sedna/)
They can't BOTH be the tenth planet, can they?
"So, you have stars, and they're easy to identify because there's this whole fusion reaction that gives off a lot of radiated energy. Everything that is too small to start the reaction is just in a different category - "not a star"."
White dwarfs and neutron stars don't have fusion...
I rarely criticize things I don't care about.
By definition, a moon/satellite doesn't have to be orbiting a planet. Check out Ida and Dactyl, an asteroid/moon combination. Anything out there that's massive can have a moon, it doesn't need to be a planet or even the size of a planet. Ida is only 31 km in diameter (on average), and its moon is only 0.7 km in diameter. By 2002, there were over 30 discovered asteroid/moon systems. As far as I'm concerned, the fact that it has a moon shouldn't have any bearing on whether or not it's a planet. We have planets (Mercury and Venus) which have no moons at all, and we have non-planets which do have moons.
The best way to predict the future is to invent it.
There could even be a companion brown dwarf that we haven't detected so far.
A name has been proposed for just such a sister star: Nemesis. First time I read about it was in Carl Sagan's book "Comet", and Mr. Sagan expounds a theory that would explain the cyclical mass extintions Earth seems to be prone to. In a nutshell, Nemesis swings close by once every 22 million years or so, close enough to penetrate the Oort Cloud, hurtling countless comets towards the inner solar system, and at least one of those is bound to smash into the Earth. The moment I suddenly see fifty comets all at once in the sky is the moment I head towards the hills, although I doubt that would do much good.
Lil' Thindime, lilting a lacrimose lament, krashes the kwaint konfines of Kokonino Kounty