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Argos
2006-Jun-06, 03:36 PM
http://space.com/scienceastronomy/060605_planemos.html


Planet-like objects floating alone through space harbor disks of material that could make other planets or moons, something like miniature versions of our solar system, astronomers said today.

I think itīs time to have a thread on planet definition...:razz:

antoniseb
2006-Jun-06, 03:41 PM
I seem to remember more threads than I can count on the subject of planet definition. I haven't grown attached to the word "planemo" yet, but I'm glad to have a word to describe something smaller than a brown dwarf that isn't orbiting a star.

parallaxicality
2006-Jun-06, 04:43 PM
To me, the word is just a semantic fudge. I weigh roughly 200 pounds. My bookshelf probably weighs about the same. I am therefore a "bookshelf-mass object", but that doesn't make me a bookshelf. Gibor Basri's ideas are good at keeping the universe nice and tidy, but ultimately they don't really answer any questions.

Argos
2006-Jun-06, 04:53 PM
Language is a virus from outer space... ;)

HenrikOlsen
2006-Jun-06, 05:21 PM
To me it sounds like one of those words that makes people ask the wrong questions about the object.

Eckelston
2006-Jun-06, 06:47 PM
To me, the word is just a semantic fudge. I weigh roughly 200 pounds. My bookshelf probably weighs about the same. I am therefore a "bookshelf-mass object", but that doesn't make me a bookshelf. Gibor Basri's ideas are good at keeping the universe nice and tidy, but ultimately they don't really answer any questions.

But what if you really did look like a bookshelf only you went to work every morning, spent the evening in the bar with friends, played baseball with the kids (who looked like really small bookshelves) in the weekendl etc. Would that make you a bookshelf? ;)

Seriously I prefer the term rogue planet. I know some people will say that it implies it was ejected from a solar system but at least it doesn't have this What the heck? effect.

Argos
2006-Jun-06, 06:58 PM
To me it sounds like one of those words that makes people ask the wrong questions about the object.

Like QUASAR, MACHO? :)

NEOWatcher
2006-Jun-06, 07:22 PM
My bookshelf probably weighs about the same. I am therefore a "bookshelf-mass object", but that doesn't make me a bookshelf.
But it does make you "shelf-ish" :D

loglo
2006-Jun-06, 07:42 PM
To me it sounds like one of those words that makes people ask the wrong questions about the object.

Why not just call them "planetos"? Then call minor planets "planetis". At least that way people would have a rough idea what astronomers are talking about. Planemos sounds like a medical condition to me. :D

Ara Pacis
2006-Jun-06, 09:44 PM
http://space.com/scienceastronomy/060605_planemos.html



I think itīs time to have a thread on planet definition...:razz:

Been there, done that.

So when will astronomers discover the Tickle-Me Planemo?

parallaxicality
2006-Jun-06, 09:46 PM
But it does make you "shelf-ish" :D


Maybe; I can be quite dangerous when undercooked.

furtim
2006-Jun-07, 08:13 AM
The term "planetary mass object" seems a bit silly to me, although the term "planemo" is undoubtedly even sillier. It just sounds bad to the ear. But "planetary mass object" inspires the question, "What's planetary mass?" I don't think there's really a consensus on what the mass of a planet is, which is of course a large part of the debate involving Pluto's status.

Furthermore, I'm not sure the term is strictly necessary. There's one quote from Kevin Luhman in the Space.com article that's rather telling: "I don't use the term planetary mass object. They are really just brown dwarfs." Later in the article, Ray Jayawardhana is quoted saying, "The reason we describe [them] as mini-solar systems is because the central objects probably formed more like stars than like planets." That just reinforces the idea that these "planemos" are actually brown dwarves! Perhaps they're smaller than other identified brown dwarves, but nothing other than that seems to require the definition of a completely new term. (And a somewhat useless term, as there's no consensus on what "planetary mass" is, as I mentioned above.)

Ara Pacis
2006-Jun-07, 09:03 AM
Maybe brown dwarfs should be called lucifers... ya know, an entity that almost made it into the light but somehow ended up in darkness instead. :D

Argos
2006-Jun-07, 12:32 PM
In science, a single word is always better than two. Thatīs why I like 'planemo'. Itīs not stranger than many others in the astronomy field. As for the public understanding, well, the public is dumb by default. Donīt expect any understanding of anything.

NEOWatcher
2006-Jun-07, 12:44 PM
In science, a single word is always better than two.
I'm curious to know why that is (from a scientific view)

As for the public understanding, well, the public is dumb by default. Donīt expect any understanding of anything.
I think this is where a single word is more valuable. Start with a public that really doesn't understand, and add in a media who will invariably drop one of the adjectives, you get sensationalism.
On the other hand, give the public a strange word. They will create thier own definition.

Argos
2006-Jun-07, 12:58 PM
I'm curious to know why that is (from a scientific view)


And so am I as to why it shouldnīt be. Well, my Science Method professors have always taught me to be economic on the scientific discourse. "Use simple words instead of the difficult; Use short words instead of the long ones; Donīt be pompous; Donīt be pedantic; Keep it simple". But of course they could be wrong.

NEOWatcher
2006-Jun-07, 01:02 PM
And so am I as to why it shouldnīt be. Well, my Science Method professors have always taught me to be economic on the scientific discourse. "Use simple words instead of the difficult; Use short words instead of the long ones; Donīt be pompous; Donīt be pedantic; Keep it simple". But of course they could be wrong.
Which is why I'm wondering. I have been taught the same thing, but I interpret that explaination as more, descriptive, simple words, not long strange words.

Argos
2006-Jun-07, 01:12 PM
It is strange because it is new.

M.A.C.H.O., QUAS.AR, GRAVASTAR, MAGNETAR, are all difficult words, at first glance. However, we wouldnīt be better off with Massive Compact Halo Object, Quasi-stellar object, and so on.

I think itīs far better than "rogue" planet, which is an imprecise (and a somewhat humanizing) expression to use in defining an object.

Ara Pacis
2006-Jun-07, 08:12 PM
You want to keep it simple but not too simple. The general american public can understand multiple word combinations fairly well. I think a good limit might be three for compactness while keeping accuracy but one word is not enough to convey a specific meaning unless the word has an unambiguous meaning. I think two would be optimal. People commonly use modifiers like adjectives and adverbs in every discussion and people are used to using two names to describe an individual. Public scientific discussions of biology routinely use two specialized words (genus and species), unless those words are difficult to pronounce. The public is not confused if you talk about Homo Sapiens, but if you cut it to just Sapiens or to just Homo you might get some blank stares.

People will expect scientists to use a modifier to change the meaning of an object that only varies from another object in single or minor ways that is easily conveyed by a common modifier. If you go on TV and talk about a Planemo most people will assume a two word combination and ask themselves "Does that come after Plan Beta?"

The public is not stupid but it is ignorant of jargon and complex astronomy. If astronomers want to continue to receive public funding they should be able to communicate to the people paying the bills. Those astronomers who are also good communicators will tell you that they like to see the wonder in the eyes of the people they talk to. Wonderment can mean awe-inspiring or it can mean bewilderment. Be careful which one your audience will feel at your words.

Argos
2006-Jun-07, 11:33 PM
I know where you come from [and I agree in part], but If the flow of funds for science depended on the public understanding of jargon, or needed fancy words, weīd already be back to the cavern. Think of all the things the public pay for, without ever knowing about. A single-word definition may be too complex for the public, but itīs perfect in the classrooms, labs and observatories, imo.

I even think the term has a certain Greek mistique that can be interesting to the public. Now, if one is using the term to "avoid the debate" as the linked article states, thatīs another story...

TwAgIssmuDe
2006-Jun-07, 11:45 PM
I have to say that a definition of the word 'planet' has to come up soon, because things are getting stranger in the world of astronomy.

Blob
2006-Jun-08, 01:48 AM
Hum,
see also the thread about the exoplanet 2M1207b (http://www.bautforum.com/showthread.php?t=13270&page=2&highlight=2M1207b)

furtim
2006-Jun-09, 02:20 AM
I think what's worse than having an obscure name is having two names for the same thing. In this case, it really does seem that these "planemos" are simply brown dwarves that have planetary systems around them. I don't see how this justifies a new name. When we talk about stars that have exoplanets, we simply call them "stars". We don't have to call them "solemos" for "solar mass object" or anything like that.

Ronald Brak
2006-Jun-09, 03:38 AM
I think science fictions writers will probably determine whatever term becomes popular. Since brown dwarf already has some popularity that is what will probably stick and they will refer to the satelites around them as planets whether learned people think that is technically accurate or not.

DARTH VADER: The rebel base is located on the fourth planet orbiting the brown dwarf.

HENCHMAN: Actually Lord Vader, it's the fourth satelite of the planemo. Erk! Something choking me! Can't breath...

Romanus
2006-Jun-09, 04:40 AM
I prefer to keep it simple; without getting into the hairier area of planet and asteroid/whatever distinctions, I'd separate planets and stars according to mass, and if a "planet" is unattached to any star, just call it a rogue planet.

My two bits.

Ara Pacis
2006-Jun-09, 06:47 AM
The term Rogue Planet seems straightforward enough. It's an object that is in all detectable ways similar to what is popularly called a planet except location. Even rogue planets probably form as solar planets that simply leave that orbit. Call it a Rogue, Exo-planet, wandering planet (hows that for redundancy?) or some other type of prefixed-planet.

parallaxicality
2006-Jun-09, 07:13 AM
I just realised how ludicrous the idea of a planemo is.

A planemo is a "planetary mass object", hence, it is an object the size of a planet.

A planet is a planemo in orbit around a fusor.

Therefore a planet is an object the size of a planet in orbit around a fusor.

Which means it is an object the size of an object the size of an object the size of an object.... in orbit around a fusor.

Argos
2006-Jun-09, 01:06 PM
What an ingratitude... A guy generously coins a cool term trying to put some order in a fuzzy subject, only be slammed planetwide [or planemo-wide? :shifty:].

:)

Ara Pacis
2006-Jun-09, 07:28 PM
Maybe we should stop calling human space travelors astronauts or even cosmonauts and start calling them anthropemos (Anthropic massive objects)

Argos
2006-Jun-09, 09:58 PM
That would be cool. :)