And I tell people that, when the subject of the Fomalhaut discovery comes up, and they just glaze over. The number of people that are actually fascinated by these discoveries seems to be somewhat low.. or interested, even.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin
"Ignorance convinces" -- slang's dad
"Your right to hold an opinion is not being contested. Your expectation that it be taken seriously is." -- Jason Thompson

Don't know how you came to this conclusion.

But let me try and work this out:

1. Brown dwarves = greater than 13 Jupiter masses by definition, and burn deuterium - hence, Brown dwarves are stars, not planets
2. An object orbiting a brown dwarf which is less than 13 Jupiter masses and does not burn deuterium is a planet.

An object fitting #3's description has indeed been discovered orbiting an object matching #1's description, so yes:

At least one planet has indeed been discovered orbiting a brown dwarf, which * is * a star according to the IAU definition. It defines an object 13 Jupiter masses or more, deuterium burning, as fitting the description of a star - as that is exactly what a brown dwarf is: between 13 mJ and Red Dwarf in mass, and burning deuterium but not hydrogen and helium.

They are not main-sequence stars but they are indeed stars, IMO and according to the IAU definition you laid out.

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Do you have a reference for that claim? It contradicts the IAU working definition.

Here's one. It's an Internet encyclopedia, but I've seen the same conclusions in many other places on the Internet.

http://www.daviddarling.info/encyclo...rowndwarf.html

A brown dwarf masses between 13 Jupiter masses and 84 Jupiter masses.

Here's a few links on a few brown dwarfs that fit within that mass range.

Kelu 1 is no more than 75 Jupiter masses

http://www.eso.org/public/outreach/p.../pr-07-97.html

Gliese 229 b is between 25 and 65 Jupiter masses

http://www.solstation.com/stars/gl229.htm

And here's a link on an abstract suggesting that the deuterium burning limit may be used to distinguish brown dwarfs from stars.

http://gpd.jhuapl.edu/abstracts/abst...d_abstract.pdf

I'm afraid you're reading it incorrectly - it is not an exhaustive definition for extrasolar planets. It says that planetary-mass objects orbiting stars are planets, but does not say that only such objects are planets.

As the WGESP position statement says: "Rather than try to construct a detailed definition of a planet which is designed to cover all future possibilities, the WGESP has agreed to restrict itself to developing a working definition applicable to the cases where there already are claimed detections, e.g., the radial velocity surveys of companions to (mostly) solar-type stars, and the imaging surveys for free-floating objects in young star clusters. As new claims are made in the future, the WGESP will weigh their individual merits and circumstances, and will try to fit the new objects into the WGESP definition of a 'planet', revising this definition as necessary."

I assume frank discussion are now taking place!

This seems to be the case. I believe there is much more opportunity here to make this a big story, but it's not happening. Perhaps this is another frog in the pot analogy. Over the last decade there have been over 300 discoveries of exoplanets. Fomalhaut b is not the first to be imaged, either, and when it was announced, along came the announcment of three planets imaged, as we know. All of these points has kept the frog leaping up and getting everyone's attention.

I suspect something extra has to get the frog out of the pot. In my amateur opinion, I believe Fomalhaut b should be lifted to the proverbial pedestal since it is the first visible exoplanet imaged. This distinction isn't to minimalize the great efforts by others in imaging and infering the others, but I think Fomalhaut b should be given exceptional recognition for the good it should do for astronomy as a whole.

However, it wouldn't shock me if I am missing some points here. Y'all's views are important. I would like to be a part of something special in recognizing this discovery, even if it's just sending flowers or gift certificates to the Fb team.

If this idea has merit in your opinion, we might want to do a thread on what we as supporters can do to help in recognizing such an event.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

<Cynic mode on>
I think you may be overestimating the general population. Remember Solid Bismuth's thread? Sadly, most people don't care, and probably won't care until the day a Vulcan drops in to dinner.
<Cynic mode off>

I like your idea of doing something to recognise this achievement George.

Hey, please keep "what is a planet" stuff out of this thread, this is about extrasolar planet discoveries.

PS. It's "dwarfs", not "dwarves". The latter can be found in Tolkien's books.

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Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

What does that mean?

I don't see the relevance of anything you have posted above to the question of whether objects orbiting brown dwarves are planets.

Agreed, and their apothy is apparent. But, I am not talking of them so much as us -- the ones that really respect what astronomers accomplish. What can we do to express honor?

But, first I want to know if I'm off base on my thinking. From a landmark case perspective, Fomalhaut b may be the most interesting exoplanet to date simply because of the visible imaging (no so much the planet itself).

Either I'm right or wrong, what say thee?

[If I'm right, we can start a new thread. If nothing else, we can send a copy of a congrats thread of all our comments, but I'd love to see something more grand and commencerate to their milestone accomplishment. ]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Sorry, I misunderstood. I thought you were saying that the definition said that anything over 13 Jupiter masses and burning deuterium was classified, by the definition as being a star. In my own defence, I was suffering from lack of sleep at the time I posted all those links.

And, that's the last thing I'll post about the definition of stars, since we were politely asked to knock if off.

I still disagree, though, with the definition of planets. I think it's more relevant the way an object was formed than what it orbits around. It's silly that you might have two gas giants, formed in exactly the same way, with almost exactly the same composition, with one being classed as a planet (because it orbits, say, a red dwarf) and the other not (because it orbits a brown dwarf). Would Earth suddenly stop being a planet if it were transported to an orbit around a brown dwarf? Would an object around a brown dwarf suddenly become a planet if it were captured a star?

You're not wrong George.
I am a little perplexed though. Is there a reason why everyone is more excited about Fomalhaut b than the three planets around HR8799? Because I thought those images were fantastic. Is it the infrared/visible divide? Becuase that seems like wavelength elitism to me.

My guess is partly due to the fame of the star in question and partly because of the distance. Fomalhaut is much better known, and it has a proper name and not a bunch of letters and numbers. I imagine a lot of people hadn't even heard of HR 8799 before this news broke and it has a designation virtually identical to a lot of other stars out there. Fomalhaut is also much closer, being only 25 light years away, as opposed to Hr 8799's 129 light years.

It's sort of like suddenly finding out something cool about two people, one an acquaintance, someone you've been sort of aware of for some time, who has a unique name, and who lives close by, and one a virtual stranger who lives a fair distance away and who's name is Bob Jones. It's just easier to be interested in the acquaintance.

Ah. Fair enough.

I'm not sure why you are objecting.

One of the most exciting things about the area of extrasolar planet research is that these objects throw our definitions of planet vs. star vs. brown dwarf into question.

Trying to find the best possible defintion of what each of those things actually is seems entirely relevant to the discussion of interesting extrasolar planet discoveries.

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It probably does boil down to comparing HR8799's to Fomalhaut's exoplanet.

Pros for Fomalhaut b
1) It is the first confirmed directly imaged exoplanet in visible light. [Is it the first direct imaged exoplanet if we go back, since it was imaged in 2004 and I assume even then it was in visible light, right?] This first is unique from the rest and its too late to crank-up the band, I think, for an IR imaged exoplanet.

2) Warmer fuzzies with name familiarity vs. a number designation (as t@nn stated).

2b) "Fomalhaut" is kinda fun to say. [My 3 yr. old niece thought bread pudding made no sense as why make pudding from just bread. Then she said "bread pudding", smiled and said, "That's fun to say!".]

3) The host star is bright and easily visible to the naked eye with mag. of about 1. [HR8799 is not really visible to most naked eyes with its mag. of about 6.]

4) The actual image from Hubble is stunning. Though impressive, the HR8799 image looks like something out of CERN instead of from Keck, at least the few images I've seen.

I still pose the question, repharasing... "Should we wake-up the slumbering cheerleaders and get them to celebrate one of these discoveries, or must we wait till we discover a stargate or something?"

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.