Re: [meteorite-list] OT: HOW MANY PLANETS?
Hi, Darren, Doug, OK, I didn't do the math, and you can forget that, as it's a complex simulation that's required; the number of factors is staggering. I did do the research, though, reading a few (hundred) pages on the theoretical models of icy rocky and gassy only bodies. First, the existence of sub-Jovian, Jovian, and super-Jovian bodies in close orbits at high temperatures around other stars convinces me that a hot gas giant is a possibility, since they obviously exist! John S. Lewis, who developed many of the early theoretical models of structure for such bodies back in the when, wrote a book on the new extra-solar worlds, Worlds Without End, and he discusses the hot giants. These's no theoretical problem; they're keepers. Second, it is really difficult to boil away a planet like Darren first suggested in his orbit swapping example. Even a Plutonian sized body would merely evolve over many millions of years, not evaporate. Third, these Plutonians I have been talking about are not all volatiles, like so many who dislike them suggest, not giant comets. What I probably didn't make clear writing about them is that they are made from primordial planetesimals, the equivalent of condensing them directly from the solar nebula without any extensive thermal modification. In other words, they accreted out where the nebula was cool, about 160 K and below. The solar nebula is, er, was 60% volatiles and 40% rock. The rock has already formed out at 160 K. as grains, dust, pebbles, chunks, etc. In low vapor pressure space, the water (and uranium oxides, oddly enough) condense and accumulate at 160's K. There is some accretional heating and about 20% of the volatiles were driven off as the bodies formed. The resulting planets are therefore about 50%/50% volatiles and rock. This is easy to determine when you can get a density for these bodies where possible and probably applies equally well to all or most of them. The larger Plutonian bodies are certain to differentiate, leaving a rocky core and a volatiles crust and mantle. The use of the word volatiles is very mis-leading here. At these temperatures and pressures, they should be regarded as cryogenic minerals, with a substantial fraction of the strength of the silicate minerals of rock. A Plutonian body like 2003UB313 will achieve central pressures of 100,000 bar, or 1,500,000 lb/in^2. Ices have crystal structures that collapse nicely into each other at far lesser pressures and produce a resultant crystal that is very strong, rigid, tightly bonded, nearly metallic in some cases. Their phase diagrams are highly complex, not as simple as a mere rock's. (I sneer at petrologists here.) The interaction of the variety of these volatiles is even more complex. The eutectic melting of ammonia and water mixtures will drive you crazy if you study it long enough, believe me. In other words, there is kind of weather possible on a Plutonian body as close in Jupiter's orbit, and obviously Titan is a place where you need an umbrella AND a warm coat and are encouraged not to jump in the methane puddles (too cool for ammonia/water weather). The Jovian moons are the model of what a Plutonian world would be like. Pluto is just Ganymede (bigger than Mercury) cooled down to 109 K. Next is a really obvious point seems to elude a lot of heavy thinkers. Jupiter and the other gas giants did not capture every Plutonian world; some, probably most, escaped, ejected into the outer system. Now, which ones got away: the little ones or the big ones? Doh. Yes, even the biggest gravitational fisherman of all, Jupiter, had the big one(s) that got away! That's BIGGER than Ganymede, Europa, Callisto, Io. Maybe the Jovian satellites formed in place; maybe not. I say not. All the other gas giant moons look like captures -- them too, sez I. This is not say that the Plutonian bodies accreted at 5 AU, only that that's the minimum distance. They could (and presumably did) accrete anywhere out from there, although exactly where is a mystery for a while. This why one could be (and still can be) confident of finding large outer system bodies like 2003UB313 and its undiscovered and still larger companion planets. I said planets, IAU. It should not have been a surprise! It probably was not to the successful searchers, but a certain number of minds seem to be struggling with reality here. Hey, wait, you say, Jupiter's moon IO is not Plutonian! Ah, but it is. You take a 50/50 ice/rock Plutonian body, tidally heat it for billions of years, drive off the water and other volatiles slowly. The hot water reacts with the abundant sulfides in the solar mix which are converted to sulfur and sulfur oxides, too heavy to escape. You are left with the rocky core (80% of the original diameter) covered with bubbling sulfur circuses! THIS is the answer to Darren's original question: what would happen if you took Pluto
Re: [meteorite-list] OT: HOW MANY PLANETS?
As always, simplifying a tangled web. Informative AND entertaining. I'm glad I'm not the only audience enthralled by this interchange between yourself, Darren, Doug et al. Thanks to all. The Meteorite List LIVES!!! It is a living entity breaching the ceiling of the heavens, gulping the ether and beching organic plasma. It incites thought, passion and a zest for living. It helps remind one of the wonderous fabric woven so adroitly still beyond our complete understanding. But we strive, we strive, we strive. What exciting times!!! Space Exploration and Earth based Astronomy take us to new heights making our star rocks ever more precious to each of us! - Original Message - From: Sterling K. Webb [EMAIL PROTECTED] To: [EMAIL PROTECTED]; [EMAIL PROTECTED]; meteorite-list@meteoritecentral.com Sent: Thursday, August 04, 2005 6:53 PM Subject: Re: [meteorite-list] OT: HOW MANY PLANETS? Hi, Darren, Doug, OK, I didn't do the math, and you can forget that, as it's a complex simulation that's required; the number of factors is staggering. I did do the research, though, reading a few (hundred) pages on the theoretical models of icy rocky and gassy only bodies. First, the existence of sub-Jovian, Jovian, and super-Jovian bodies in close orbits at high temperatures around other stars convinces me that a hot gas giant is a possibility, since they obviously exist! John S. Lewis, who developed many of the early theoretical models of structure for such bodies back in the when, wrote a book on the new extra-solar worlds, Worlds Without End, and he discusses the hot giants. These's no theoretical problem; they're keepers. Second, it is really difficult to boil away a planet like Darren first suggested in his orbit swapping example. Even a Plutonian sized body would merely evolve over many millions of years, not evaporate. Third, these Plutonians I have been talking about are not all volatiles, like so many who dislike them suggest, not giant comets. What I probably didn't make clear writing about them is that they are made from primordial planetesimals, the equivalent of condensing them directly from the solar nebula without any extensive thermal modification. In other words, they accreted out where the nebula was cool, about 160 K and below. The solar nebula is, er, was 60% volatiles and 40% rock. The rock has already formed out at 160 K. as grains, dust, pebbles, chunks, etc. In low vapor pressure space, the water (and uranium oxides, oddly enough) condense and accumulate at 160's K. There is some accretional heating and about 20% of the volatiles were driven off as the bodies formed. The resulting planets are therefore about 50%/50% volatiles and rock. This is easy to determine when you can get a density for these bodies where possible and probably applies equally well to all or most of them. The larger Plutonian bodies are certain to differentiate, leaving a rocky core and a volatiles crust and mantle. The use of the word volatiles is very mis-leading here. At these temperatures and pressures, they should be regarded as cryogenic minerals, with a substantial fraction of the strength of the silicate minerals of rock. A Plutonian body like 2003UB313 will achieve central pressures of 100,000 bar, or 1,500,000 lb/in^2. Ices have crystal structures that collapse nicely into each other at far lesser pressures and produce a resultant crystal that is very strong, rigid, tightly bonded, nearly metallic in some cases. Their phase diagrams are highly complex, not as simple as a mere rock's. (I sneer at petrologists here.) The interaction of the variety of these volatiles is even more complex. The eutectic melting of ammonia and water mixtures will drive you crazy if you study it long enough, believe me. In other words, there is kind of weather possible on a Plutonian body as close in Jupiter's orbit, and obviously Titan is a place where you need an umbrella AND a warm coat and are encouraged not to jump in the methane puddles (too cool for ammonia/water weather). The Jovian moons are the model of what a Plutonian world would be like. Pluto is just Ganymede (bigger than Mercury) cooled down to 109 K. Next is a really obvious point seems to elude a lot of heavy thinkers. Jupiter and the other gas giants did not capture every Plutonian world; some, probably most, escaped, ejected into the outer system. Now, which ones got away: the little ones or the big ones? Doh. Yes, even the biggest gravitational fisherman of all, Jupiter, had the big one(s) that got away! That's BIGGER than Ganymede, Europa, Callisto, Io. Maybe the Jovian satellites formed in place; maybe not. I say not. All the other gas giant moons look like captures -- them too, sez I. This is not say that the Plutonian bodies accreted at 5 AU, only that that's the minimum distance. They could (and presumably did) accrete anywhere out from there, although exactly
[meteorite-list] OT: HOW MANY PLANETS?
Hi, All, Brian Marsden, in the article below: http://www.space.com/scienceastronomy/050802_planet_definition.html is quoted as saying if the Stern definition of a planet were used (everything spherical that goes 'round its star and doesn't fusion inside), we'd have 24 planets. Marsden himself says, The only sensible solution is to accept that the solar system contains the eight planets known a century or so ago, Marsden said via email, and to add new members only if they are larger than, say, Mars -- or maybe even the Earth. Of course, this way, Marsden, who's is charge of Minor Planets gets to keep'em and add Pluto to his collection. Stern says of the Kuiper Belt, It's really a revolution, says Alan Stern of the Southwest Research Institute. We are finding out just how quaint our view of the solar system was. My definition (everything spherical and bigger than Ceres that goes around the sun), by excluding the four large minor planets, would give us 20 planets. As for students and degree of difficulty, what makes you think high school students learn ANYTHING anyway? Stern is on that IAU committee defining a planet, BTW. The IAU and astronomy generally have a dilemma, though. How can you say that the massive 2003UB313 is NOT a planet when the smaller Pluto IS? However, we've got time. It will be a while before we get out there and have to found the Chamber of Commerce and name the MacDonalds on SEDNA or QUOAOR... A little bar down by the spaceport, The Inn of the 37 Planets, or call a subdivision 10th Planet Estates! What if nobody wants to LIVE on the 13th Planet? A lot of old office buildings DON'T HAVE a 13th floor... 11, 12, 14, 15, 16... Sterling Webb __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
Brian Marsden, in the article below: http://www.space.com/scienceastronomy/050802_planet_definition.html is quoted as saying if the Stern definition of a planet were used (everything spherical that goes 'round its star and doesn't fusion inside), we'd have 24 planets. Marsden himself says, The only sensible solution is to accept that the solar system contains the eight planets known a century or so ago, Marsden said via email, and to add new members only if they are larger than, say, Mars -- or maybe even the Earth. It will be interesting to see what the IAU finally decides upon. I personally think the definition should take into account the size and orbit, and the object should be relatively unique. My definition (everything spherical and bigger than Ceres that goes around the sun), by excluding the four large minor planets, would give us 20 planets. My personal opinion is that the asteroids in the main asteroid belt are not major planets. They can be easily excluded with a minimum size specification. The IAU and astronomy generally have a dilemma, though. How can you say that the massive 2003UB313 is NOT a planet when the smaller Pluto IS? I can think of two ways. I think the object orbit's should be a factor in defining a planet. 2003 UB313 is inclined at 44 degrees, so if you exclude object above 20 degrees inclination, then Pluto would be in and 2003 UB313 is out. Another way is just make Pluto an exception to the rule, and have it retain its planetary status. We have precedences for this. A platypus lays eggs, but is still considered a mammal. Europa and Asia are considered separate continents even though they are a single combined land mass. Incidently, if you demote Pluto from being a planet, then the definition for a planet becomes much easier. If you include Pluto as a planet, then the definition is going to get more complicated. Ron Baalke __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
Ron B. wrote: Incidently, if you demote Pluto from being a planet, then the definition for a planet becomes much easier. If you include Pluto as a planet, then the definition is going to get more complicated. Complicated it can be, not dumbed down, with or without Pluto. Arbitrary numerical criteria are useless to science in the long run whether they be 9 units, 20 degrees or 3025 miles. They are more like taxing authorities saying...if you own more than 20% of the company's stock, you must make special declarations. That is a foolish angle for the IAU to put itself in, and more typical of the thinking of mediocre government employees or bureacrats looking to reduce their workloads (not that we aren't all guilty at times). My personal thoughts of a planet rely on a permanent atmosphere or proven or potential geological process (major igneous activity, liberally considered) basis and prime orbit about the Sun. If Earth suddenly was catapulted into a 25 degree inclination ...would it cease being a planet? Perhaps my definition even excludes Pluto by not for a senseless inclination cutoff, especially after its hypothetical encounter with Neptune sent it there, or perhaps not. Vesta is always as bright or brighter than Neptune, and occasionally trumps Uranus, so something is out of wack here...the ancients would have called Vesta a wanderer if they didn't carelessly overlook documenting it. (It owes that brightness to 'geo'logical processes, namely the reflectivity of eucrite.) If Earth were catapulted into the Kuiper Belt would it cease being a planet? Wait until an Earth sized ball is found out there...How about Differentiated Planets, Gaseous Planets, and Frozen Planets to replace the inner and outer planets? Remember - for minor planets, a comet for all practical purposes becomes an asteroid - but it is still a minor planet, under current use... Kids can still memorize the Inner, Gaseous and Pluto (because Pluto is sometimes closer than Neptune, a very very important criterion from an earthly viewpoint of numbering successively the billiard balls starting with the bright white cue, and all you have to do is say the first 9 planets out..) Saludos, Doug __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
And one other way... they can simply refuse to define planet at all, since there is no need to do so. But that would be too simple. Chris * Chris L Peterson Cloudbait Observatory http://www.cloudbait.com - Original Message - From: Ron Baalke [EMAIL PROTECTED] To: Meteorite Mailing List meteorite-list@meteoritecentral.com Sent: Wednesday, August 03, 2005 4:28 PM Subject: Re: [meteorite-list] OT: HOW MANY PLANETS? The IAU and astronomy generally have a dilemma, though. How can you say that the massive 2003UB313 is NOT a planet when the smaller Pluto IS? I can think of two ways. I think the object orbit's should be a factor in defining a planet. 2003 UB313 is inclined at 44 degrees, so if you exclude object above 20 degrees inclination, then Pluto would be in and 2003 UB313 is out. Another way is just make Pluto an exception to the rule, and have it retain its planetary status. We have precedences for this. A platypus lays eggs, but is still considered a mammal. Europa and Asia are considered separate continents even though they are a single combined land mass. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
Any classification scheme can be revised - and in fact, should be allowed to be revised when new data presents itself. If Earth suddenly was catapulted into a 25 degree inclination ...would it cease being a planet? No. The classification scheme will be revised to accomodate any new data. If Earth were catapulted into the Kuiper Belt would it cease being a planet? If that were to happen, then quite frankly, it really wouldn't matter at that point, would it? :-) Ron Baalke __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
On Wed, 3 Aug 2005 19:14:22 EDT, [EMAIL PROTECTED] wrote: If Earth were catapulted into the Kuiper Belt would it cease being a planet? An even better question (IMHO) is-- if a KBO were to be brought in to 1 AU, would it still be concidered a planet? What about a few years later when half (give or take) of it had sublimated away and left nothing but a ring of rubble? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
Doug, Sterling, and all you other amazing brains, (Deity or planetary name of your choice), it's good to to listen to you guys with IQs in the clouds. Some people do word-searches or crosswords to exercize their brains. For some of us, it's the MetList. Thanks (and Garcias to you, Doug---) Norm http://tektitesource.com --- [EMAIL PROTECTED] wrote: Ron B. wrote: Incidently, if you demote Pluto from being a planet, then the definition for a planet becomes much easier. If you include Pluto as a planet, then the definition is going to get more complicated. Complicated it can be, not dumbed down, with or without Pluto. Arbitrary numerical criteria are useless to science in the long run whether they be 9 units, 20 degrees or 3025 miles. They are more like taxing authorities saying...if you own more than 20% of the company's stock, you must make special declarations. That is a foolish angle for the IAU to put itself in, and more typical of the thinking of mediocre government employees or bureacrats looking to reduce their workloads (not that we aren't all guilty at times). My personal thoughts of a planet rely on a permanent atmosphere or proven or potential geological process (major igneous activity, liberally considered) basis and prime orbit about the Sun. If Earth suddenly was catapulted into a 25 degree inclination ...would it cease being a planet? Perhaps my definition even excludes Pluto by not for a senseless inclination cutoff, especially after its hypothetical encounter with Neptune sent it there, or perhaps not. Vesta is always as bright or brighter than Neptune, and occasionally trumps Uranus, so something is out of wack here...the ancients would have called Vesta a wanderer if they didn't carelessly overlook documenting it. (It owes that brightness to 'geo'logical processes, namely the reflectivity of eucrite.) If Earth were catapulted into the Kuiper Belt would it cease being a planet? Wait until an Earth sized ball is found out there...How about Differentiated Planets, Gaseous Planets, and Frozen Planets to replace the inner and outer planets? Remember - for minor planets, a comet for all practical purposes becomes an asteroid - but it is still a minor planet, under current use... Kids can still memorize the Inner, Gaseous and Pluto (because Pluto is sometimes closer than Neptune, a very very important criterion from an earthly viewpoint of numbering successively the billiard balls starting with the bright white cue, and all you have to do is say the first 9 planets out..) Saludos, Doug __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
Darren G. wrote: if a KBO were to be brought in to 1 AU, would it still be concidered a planet? What about a few years later when half (give or take) of it had sublimated away and left nothing but a ring of rubble? Great balls of Fire! Meteorite heaven and a lot of new iridium stratigraphy to work out, though Ron might not be as upbeat about the whole proposition worrying about finding some high ground to store his meteorites just before the potential for another great terrestrial deluge:) Darren, if we swapped Uranus with Earth something similar to what you envision might happen to Uranus at 1 AU as well...though your point is a good one to mull over... PS I got a private message complaining that having an atmosphere was too subjective a criterion to define a planet. I agree, bad choice. The revised definition is or its atmosphere gives rise to visible meteors when colliding with cometary dust. I.e., there is something for meteor observers and meteorite hunters to do. Saludos, Doug __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
On Wed, 3 Aug 2005 20:12:01 EDT, [EMAIL PROTECTED] wrote: Darren, if we swapped Uranus with Earth something similar to what you envision might happen to Uranus at 1 AU as well...though your point is a good one to mull over... I haven't done the math on it (and to be honest, would have to do a bit of brushing up before I COULD do the math) but I was thinking that the Jovans had enough gravity to hold their atmospheres even at 1 AU temperatures. Think about all of those hot Jupiters discovered over the past few years. Anyone know the mass limit for a Jovan to keep it's volitiles? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
What if nobody wants to live on the 13th planet Who write your stand up stuff? Man you're a riot - Original Message - From: Sterling K. Webb [EMAIL PROTECTED] To: Meteorite List meteorite-list@meteoritecentral.com Sent: Wednesday, August 03, 2005 6:13 PM Subject: [meteorite-list] OT: HOW MANY PLANETS? Hi, All, Brian Marsden, in the article below: http://www.space.com/scienceastronomy/050802_planet_definition.html is quoted as saying if the Stern definition of a planet were used (everything spherical that goes 'round its star and doesn't fusion inside), we'd have 24 planets. Marsden himself says, The only sensible solution is to accept that the solar system contains the eight planets known a century or so ago, Marsden said via email, and to add new members only if they are larger than, say, Mars -- or maybe even the Earth. Of course, this way, Marsden, who's is charge of Minor Planets gets to keep'em and add Pluto to his collection. Stern says of the Kuiper Belt, It's really a revolution, says Alan Stern of the Southwest Research Institute. We are finding out just how quaint our view of the solar system was. My definition (everything spherical and bigger than Ceres that goes around the sun), by excluding the four large minor planets, would give us 20 planets. As for students and degree of difficulty, what makes you think high school students learn ANYTHING anyway? Stern is on that IAU committee defining a planet, BTW. The IAU and astronomy generally have a dilemma, though. How can you say that the massive 2003UB313 is NOT a planet when the smaller Pluto IS? However, we've got time. It will be a while before we get out there and have to found the Chamber of Commerce and name the MacDonalds on SEDNA or QUOAOR... A little bar down by the spaceport, The Inn of the 37 Planets, or call a subdivision 10th Planet Estates! What if nobody wants to LIVE on the 13th Planet? A lot of old office buildings DON'T HAVE a 13th floor... 11, 12, 14, 15, 16... Sterling Webb __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] OT: HOW MANY PLANETS?
If Earth suddenly was catapulted into a 25 degree inclination ...would it cease being a planet? Not necessarily, but there wouldn't be any controversy cause there'd be no one left the testify to anything!!! Jerry - Original Message - From: [EMAIL PROTECTED] To: [EMAIL PROTECTED]; meteorite-list@meteoritecentral.com Sent: Wednesday, August 03, 2005 7:14 PM Subject: Re: [meteorite-list] OT: HOW MANY PLANETS? Ron B. wrote: Incidently, if you demote Pluto from being a planet, then the definition for a planet becomes much easier. If you include Pluto as a planet, then the definition is going to get more complicated. Complicated it can be, not dumbed down, with or without Pluto. Arbitrary numerical criteria are useless to science in the long run whether they be 9 units, 20 degrees or 3025 miles. They are more like taxing authorities saying...if you own more than 20% of the company's stock, you must make special declarations. That is a foolish angle for the IAU to put itself in, and more typical of the thinking of mediocre government employees or bureacrats looking to reduce their workloads (not that we aren't all guilty at times). My personal thoughts of a planet rely on a permanent atmosphere or proven or potential geological process (major igneous activity, liberally considered) basis and prime orbit about the Sun. If Earth suddenly was catapulted into a 25 degree inclination ...would it cease being a planet? Perhaps my definition even excludes Pluto by not for a senseless inclination cutoff, especially after its hypothetical encounter with Neptune sent it there, or perhaps not. Vesta is always as bright or brighter than Neptune, and occasionally trumps Uranus, so something is out of wack here...the ancients would have called Vesta a wanderer if they didn't carelessly overlook documenting it. (It owes that brightness to 'geo'logical processes, namely the reflectivity of eucrite.) If Earth were catapulted into the Kuiper Belt would it cease being a planet? Wait until an Earth sized ball is found out there...How about Differentiated Planets, Gaseous Planets, and Frozen Planets to replace the inner and outer planets? Remember - for minor planets, a comet for all practical purposes becomes an asteroid - but it is still a minor planet, under current use... Kids can still memorize the Inner, Gaseous and Pluto (because Pluto is sometimes closer than Neptune, a very very important criterion from an earthly viewpoint of numbering successively the billiard balls starting with the bright white cue, and all you have to do is say the first 9 planets out..) Saludos, Doug __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
