Re: [meteorite-list] Mercury data
Hi Sterling - It would ironic (at the least) if we were to go from Moon volcanoes that are really impacts all the way to Mercury impacts that are really volcanoes! http://www.nytimes.com/2011/06/17/science/space/17mercury.html Not to Hermann Burchard. To paraphrase: Many Earth impacts resulted in hotspots. Any guesses when the accretion (impact) data will actually be recovered from the planetary data sets? I think it will occur shortly after Ed Weiler is fired. E.P. __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Mercury data
Carl., Thank you so much for this very good information. So, If as you say the FeO is such a big deal. Why then would they have neglected to mention it if they found it? Is it possible Mercury is extremely depleted in FeO? I mean how could they miss it if it's there? And if it's not there. What kind of basalt would that match? Thank you. Carl -- Democracy is two wolves and a lamb voting on what to have for dinner. Liberty is a well-armed lamb contesting the vote. Carl Agee a...@unm.edu wrote: Of course it's still early days on understanding the Mercury data coming back from Messenger, but I think there are a few simple things that can be said about the two geochemical graphs that were part of the press release. The major element graph of Al/Si versus Mg/Si clearly shows that the measured Mercurian surface is similar to basaltic and mantle rocks from the Earth. They plot along the Earth array and look to be a bit more olivine-rich than mid-ocean ridge basalts, but not as olivinerich as mantle peridotites, perhaps more like Archean Earth komatiites. The measured Mercurian surface is NOT delpleted in aluminum, like Martian basalts or Angrites. Also, Messenger is clearly not measuring rocks like the lunar anorthositic highlands. The major element that is still missing from this puzzle is iron. The data do not say anything about the FeO content of the Mercurian surface -- this is a pretty big deal, and until that is known it will difficult to know exactly what we are looking at -- let alone if there is a match for any known meteorite type. The potassium/thorium plot shows that Mercury is a lot like the other terrestrial planets in terms of volatile element content. It seems to be closest to the K/Th of Mars which is quite surprising, since Mars is thought to be the most volatile rich of the rocky planets. This runs counter to the idea that the inner solar system is chemically zoned with volatile elements concentrated out at Mars and lower in towards the Sun. But who knows? Maybe Mercury formed farther from the Sun and migrated inwards. There was a brief mention of substantial amounts of sulfur, but no data in the multimedia press release, so it would be interesting to know what they mean by substantial amounts. Also, why do they think it is in the form of sulfide and not sulfate? See how important these missions of planetary exploration are and how fragmentary our understanding is? Just my opinion Carl Agee -- Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: a...@unm.edu http://epswww.unm.edu/iom/pers/agee.html __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Mercury data
Carl: My guess is that the FeO data are not ready for primetime. As I understand it the XPS and the GRS on Messenger both will produce data on FeO. So I guess we will just have to wait until more information trickles out through press releases. The good stuff will probably be presented in a special session at some high profile meeting like AGU or LPSC, which are months away – perhaps a Science or Nature issue will be coming out earlier. I think most people will not be surprised if the Mercurian surface is low in FeO. That’s what reflectance spectroscopy is already suggesting. I can think of a very low FeO achondrite that is sitting in our museum – about a ton of it! But seriously, I think that Mercury should also have ages that are not all ~4.5 Ga, more like the range in lunar basalts, so that’s an important thing to consider. A word of caution about the global datasets taken from orbit: remember that so far no shergottite basalts have been seen with Mars orbital remote sensing, the global compositions are summations of very large areas and are not like looking at a geologists outcrop, let alone a nice martian meteorite hand sample. Carl Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: a...@unm.edu http://epswww.unm.edu/iom/pers/agee.html On Mon, Jun 20, 2011 at 5:33 PM, cdtuc...@cox.net wrote: Carl., Thank you so much for this very good information. So, If as you say the FeO is such a big deal. Why then would they have neglected to mention it if they found it? Is it possible Mercury is extremely depleted in FeO? I mean how could they miss it if it's there? And if it's not there. What kind of basalt would that match? Thank you. Carl -- Democracy is two wolves and a lamb voting on what to have for dinner. Liberty is a well-armed lamb contesting the vote. Carl Agee a...@unm.edu wrote: Of course it's still early days on understanding the Mercury data coming back from Messenger, but I think there are a few simple things that can be said about the two geochemical graphs that were part of the press release. The major element graph of Al/Si versus Mg/Si clearly shows that the measured Mercurian surface is similar to basaltic and mantle rocks from the Earth. They plot along the Earth array and look to be a bit more olivine-rich than mid-ocean ridge basalts, but not as olivinerich as mantle peridotites, perhaps more like Archean Earth komatiites. The measured Mercurian surface is NOT delpleted in aluminum, like Martian basalts or Angrites. Also, Messenger is clearly not measuring rocks like the lunar anorthositic highlands. The major element that is still missing from this puzzle is iron. The data do not say anything about the FeO content of the Mercurian surface -- this is a pretty big deal, and until that is known it will difficult to know exactly what we are looking at -- let alone if there is a match for any known meteorite type. The potassium/thorium plot shows that Mercury is a lot like the other terrestrial planets in terms of volatile element content. It seems to be closest to the K/Th of Mars which is quite surprising, since Mars is thought to be the most volatile rich of the rocky planets. This runs counter to the idea that the inner solar system is chemically zoned with volatile elements concentrated out at Mars and lower in towards the Sun. But who knows? Maybe Mercury formed farther from the Sun and migrated inwards. There was a brief mention of substantial amounts of sulfur, but no data in the multimedia press release, so it would be interesting to know what they mean by substantial amounts. Also, why do they think it is in the form of sulfide and not sulfate? See how important these missions of planetary exploration are and how fragmentary our understanding is? Just my opinion Carl Agee -- Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: a...@unm.edu http://epswww.unm.edu/iom/pers/agee.html __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Mercury data
Thanks, Carl. That's was what I was hoping for. There are two Theories of Mercury --- the old one, that Mercury formed from inner disk materials, all iron and refractories, and the new one, that Mercury suffered a Giant Impact' which added its iron to the Mercurian core but blasted Mercury's crust off to be lost. Sometimes the Giant Impact Theory is interpreted as a much-larger Mercury that lost much of its crust to a series of Pretty Dam Big Impacts that contributed no iron but blasted Mercury's crust off to be lost just the same. The old All Iron And Refractories theory seems, at first glance, to be dead, but wait! there's still a heart beat. The Crust is not The Planet. If Mercury has been pasted through the ages by errant asteroids and comets from Out-System that have been tossed down into high eccentricity orbits, that crust of volatiles could be the accretion of 4 billion years of Jupiter's trash toss-out. There's a lot wrong with this idea. It's hard to deliver material to Mercury without splashing it right off into the grip of the Sun's powerful gravity, and it would take a lot of material to pave a planet miles deep. Perhaps the anomalous crust was delivered by the Late Bombardment? Sulfur, visible as yellow swirls, streaks and patches surrounding the pits that burped it, got up and screamed Volatiles! even before those scans were released. It's just like Io, but a lot hotter. It can't accumulate like it does on Io Still, if Mercury is still boiling out sulfur after billions and billions of years, it must have started with a LOT of volatiles. Recent images of Mercury can be found at: http://www.nasa.gov/mission_pages/messenger/multimedia/mercury_images_coll_archive_1.html Maybe Mercury formed farther from the Sun and migrated inwards... It's a whole new solar system. Jumpin' Jupiter wandering back and forth . Now, we have Migrating Mercury. The problem is migrated from where? Where do huge-iron-cored terrestrial planets with scads of volatiles form? It's really hard to think of any spot that provides vast amounts of both. Sterling K. Webb --- - Original Message - From: Carl Agee a...@unm.edu To: meteorite-list@meteoritecentral.com Sent: Sunday, June 19, 2011 11:16 AM Subject: [meteorite-list] Mercury data Of course it's still early days on understanding the Mercury data coming back from Messenger, but I think there are a few simple things that can be said about the two geochemical graphs that were part of the press release. The major element graph of Al/Si versus Mg/Si clearly shows that the measured Mercurian surface is similar to basaltic and mantle rocks from the Earth. They plot along the Earth array and look to be a bit more olivine-rich than mid-ocean ridge basalts, but not as olivinerich as mantle peridotites, perhaps more like Archean Earth komatiites. The measured Mercurian surface is NOT delpleted in aluminum, like Martian basalts or Angrites. Also, Messenger is clearly not measuring rocks like the lunar anorthositic highlands. The major element that is still missing from this puzzle is iron. The data do not say anything about the FeO content of the Mercurian surface -- this is a pretty big deal, and until that is known it will difficult to know exactly what we are looking at -- let alone if there is a match for any known meteorite type. The potassium/thorium plot shows that Mercury is a lot like the other terrestrial planets in terms of volatile element content. It seems to be closest to the K/Th of Mars which is quite surprising, since Mars is thought to be the most volatile rich of the rocky planets. This runs counter to the idea that the inner solar system is chemically zoned with volatile elements concentrated out at Mars and lower in towards the Sun. But who knows? Maybe Mercury formed farther from the Sun and migrated inwards. There was a brief mention of substantial amounts of sulfur, but no data in the multimedia press release, so it would be interesting to know what they mean by substantial amounts. Also, why do they think it is in the form of sulfide and not sulfate? See how important these missions of planetary exploration are and how fragmentary our understanding is? Just my opinion Carl Agee -- Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: a...@unm.edu http://epswww.unm.edu/iom/pers/agee.html __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list
Re: [meteorite-list] Mercury data
Mercury or not, whatever the Angrite parent body is/was is sure to be interesting once it is figured out. The oxygen isotope analysis sure points to a large, differentiated parent body. It makes me wonder about the moons in the Jovian system. Ganymede, for example, is larger than Mercury (currently) is; I wonder if we have any Ganymeteorites in our collections waiting to be discovered? Food for thought, -Michael in so. Cal. On Sun, Jun 19, 2011 at 3:59 PM, Sterling K. Webb sterling_k_w...@sbcglobal.net wrote: Thanks, Carl. That's was what I was hoping for. There are two Theories of Mercury --- the old one, that Mercury formed from inner disk materials, all iron and refractories, and the new one, that Mercury suffered a Giant Impact' which added its iron to the Mercurian core but blasted Mercury's crust off to be lost. Sometimes the Giant Impact Theory is interpreted as a much-larger Mercury that lost much of its crust to a series of Pretty Dam Big Impacts that contributed no iron but blasted Mercury's crust off to be lost just the same. The old All Iron And Refractories theory seems, at first glance, to be dead, but wait! there's still a heart beat. The Crust is not The Planet. If Mercury has been pasted through the ages by errant asteroids and comets from Out-System that have been tossed down into high eccentricity orbits, that crust of volatiles could be the accretion of 4 billion years of Jupiter's trash toss-out. There's a lot wrong with this idea. It's hard to deliver material to Mercury without splashing it right off into the grip of the Sun's powerful gravity, and it would take a lot of material to pave a planet miles deep. Perhaps the anomalous crust was delivered by the Late Bombardment? Sulfur, visible as yellow swirls, streaks and patches surrounding the pits that burped it, got up and screamed Volatiles! even before those scans were released. It's just like Io, but a lot hotter. It can't accumulate like it does on Io Still, if Mercury is still boiling out sulfur after billions and billions of years, it must have started with a LOT of volatiles. Recent images of Mercury can be found at: http://www.nasa.gov/mission_pages/messenger/multimedia/mercury_images_coll_archive_1.html Maybe Mercury formed farther from the Sun and migrated inwards... It's a whole new solar system. Jumpin' Jupiter wandering back and forth . Now, we have Migrating Mercury. The problem is migrated from where? Where do huge-iron-cored terrestrial planets with scads of volatiles form? It's really hard to think of any spot that provides vast amounts of both. Sterling K. Webb --- - Original Message - From: Carl Agee a...@unm.edu To: meteorite-list@meteoritecentral.com Sent: Sunday, June 19, 2011 11:16 AM Subject: [meteorite-list] Mercury data Of course it's still early days on understanding the Mercury data coming back from Messenger, but I think there are a few simple things that can be said about the two geochemical graphs that were part of the press release. The major element graph of Al/Si versus Mg/Si clearly shows that the measured Mercurian surface is similar to basaltic and mantle rocks from the Earth. They plot along the Earth array and look to be a bit more olivine-rich than mid-ocean ridge basalts, but not as olivinerich as mantle peridotites, perhaps more like Archean Earth komatiites. The measured Mercurian surface is NOT delpleted in aluminum, like Martian basalts or Angrites. Also, Messenger is clearly not measuring rocks like the lunar anorthositic highlands. The major element that is still missing from this puzzle is iron. The data do not say anything about the FeO content of the Mercurian surface -- this is a pretty big deal, and until that is known it will difficult to know exactly what we are looking at -- let alone if there is a match for any known meteorite type. The potassium/thorium plot shows that Mercury is a lot like the other terrestrial planets in terms of volatile element content. It seems to be closest to the K/Th of Mars which is quite surprising, since Mars is thought to be the most volatile rich of the rocky planets. This runs counter to the idea that the inner solar system is chemically zoned with volatile elements concentrated out at Mars and lower in towards the Sun. But who knows? Maybe Mercury formed farther from the Sun and migrated inwards. There was a brief mention of substantial amounts of sulfur, but no data in the multimedia press release, so it would be interesting to know what they mean by substantial amounts. Also, why do they think it is in the form of sulfide and not sulfate? See how important these missions of planetary exploration are and how fragmentary our understanding is? Just my opinion Carl Agee -- Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary
Re: [meteorite-list] Mercury data
Hi, Sterling and All, Here's an interesting little article I came across in Nature: http://www.nature.com/nature/journal/v473/n7347/full/nature10092.html http://www.nature.com/nature/journal/v473/n7347/full/nature10092.html Unbound or distant planetary mass population detected by gravitational microlensing I know they've suspected wandering stars in the past, but now planets! If there's these big ones, what's to say there aren't smaller ones? Best, Pete From: sterling_k_w...@sbcglobal.net To: a...@unm.edu; meteorite-list@meteoritecentral.com Date: Sun, 19 Jun 2011 17:59:52 -0500 Subject: Re: [meteorite-list] Mercury data Thanks, Carl. That's was what I was hoping for. There are two Theories of Mercury --- the old one, that Mercury formed from inner disk materials, all iron and refractories, and the new one, that Mercury suffered a Giant Impact' which added its iron to the Mercurian core but blasted Mercury's crust off to be lost. Sometimes the Giant Impact Theory is interpreted as a much-larger Mercury that lost much of its crust to a series of Pretty Dam Big Impacts that contributed no iron but blasted Mercury's crust off to be lost just the same. The old All Iron And Refractories theory seems, at first glance, to be dead, but wait! there's still a heart beat. The Crust is not The Planet. If Mercury has been pasted through the ages by errant asteroids and comets from Out-System that have been tossed down into high eccentricity orbits, that crust of volatiles could be the accretion of 4 billion years of Jupiter's trash toss-out. There's a lot wrong with this idea. It's hard to deliver material to Mercury without splashing it right off into the grip of the Sun's powerful gravity, and it would take a lot of material to pave a planet miles deep. Perhaps the anomalous crust was delivered by the Late Bombardment? Sulfur, visible as yellow swirls, streaks and patches surrounding the pits that burped it, got up and screamed Volatiles! even before those scans were released. It's just like Io, but a lot hotter. It can't accumulate like it does on Io Still, if Mercury is still boiling out sulfur after billions and billions of years, it must have started with a LOT of volatiles. Recent images of Mercury can be found at: http://www.nasa.gov/mission_pages/messenger/multimedia/mercury_images_coll_archive_1.html Maybe Mercury formed farther from the Sun and migrated inwards... It's a whole new solar system. Jumpin' Jupiter wandering back and forth . Now, we have Migrating Mercury. The problem is migrated from where? Where do huge-iron-cored terrestrial planets with scads of volatiles form? It's really hard to think of any spot that provides vast amounts of both. Sterling K. Webb --- - Original Message - From: Carl Agee a...@unm.edu To: meteorite-list@meteoritecentral.com Sent: Sunday, June 19, 2011 11:16 AM Subject: [meteorite-list] Mercury data Of course it's still early days on understanding the Mercury data coming back from Messenger, but I think there are a few simple things that can be said about the two geochemical graphs that were part of the press release. The major element graph of Al/Si versus Mg/Si clearly shows that the measured Mercurian surface is similar to basaltic and mantle rocks from the Earth. They plot along the Earth array and look to be a bit more olivine-rich than mid-ocean ridge basalts, but not as olivinerich as mantle peridotites, perhaps more like Archean Earth komatiites. The measured Mercurian surface is NOT delpleted in aluminum, like Martian basalts or Angrites. Also, Messenger is clearly not measuring rocks like the lunar anorthositic highlands. The major element that is still missing from this puzzle is iron. The data do not say anything about the FeO content of the Mercurian surface -- this is a pretty big deal, and until that is known it will difficult to know exactly what we are looking at -- let alone if there is a match for any known meteorite type. The potassium/thorium plot shows that Mercury is a lot like the other terrestrial planets in terms of volatile element content. It seems to be closest to the K/Th of Mars which is quite surprising, since Mars is thought to be the most volatile rich of the rocky planets. This runs counter to the idea that the inner solar system is chemically zoned with volatile elements concentrated out at Mars and lower in towards the Sun. But who knows? Maybe Mercury formed farther from the Sun and migrated inwards. There was a brief mention of substantial amounts of sulfur, but no data in the multimedia press release, so it would be interesting to know what they mean by substantial amounts. Also, why do they think it is in the form of sulfide and not sulfate
Re: [meteorite-list] Mercury data
What they say about it: As to what to call these newfound objects, Wambsganss favors brevity. I think the most intuitive name is 'free-floating planets,' but if we decide to adopt that name then we have to give up one of our definitions of a planet, he says. A free-floating planet is a contradiction, because a planet is by definition bound in an orbit around a star. That contradiction will no doubt fuel controversy-McCaughrean calls free-floating planets, a term that appears once in the new study, a red rag to a bull. Even the more conservative free-floating planetary-mass objects can be misleading, McCaughrean says. To me, that's somewhat still equivalent to calling a Chihuahua a 'cat-massed object,' he says. http://www.scientificamerican.com/article.cfm?id=free-floating-planets-microlensing Please, somebody give their Chihuahua the name CMO... What is more, no stars were observed within 10 astronomical units of the lensing objects - one astronomical unit is the distance between the Sun and the Earth and Saturn orbits at about 9 astronomical units. http://physicsworld.com/cws/article/news/46022 Why assume they have no stars? Saturn is at 9.585 AU, BTW, not 9 AU. Couldn't we have a Jupiter at Uranus distance (20 AU)? Just because we have trouble finding Jupiters at 10 AU in distant solar systems doesn't mean they aren't there. The gravitational tug-and-wobble of a Jupiter at 10 AU is small indeed. Have we got one? http://www.popularmechanics.com/science/space/deep/our-galaxy-is-littered-with-orphan-planets-5766646 A TRILLION free planets in our Galaxy? http://www.skyandtelescope.com/news/home/122278839.html How micro-lensing works (an animation): http://planetquest.jpl.nasa.gov/news/freePlanetAnim.cfm We should remember that the orphan planets cannot be seen by the telescope, only be detected by their micro-lensing flash and if they do have stars close to them those stars would be too faint to be seen with any telescope now in operation. I have seen the dark universe yawning Where the black planets roll without aim; Where they roll in their horror unheeded, Without knowledge or lustre or name. -H. P. Lovecraft, Nemesis, 1918 Sterling K. Webb - - Original Message - From: Pete Pete rsvp...@hotmail.com To: sterling_k_w...@sbcglobal.net; a...@unm.edu; meteoritelist meteoritelist meteorite-list@meteoritecentral.com Sent: Sunday, June 19, 2011 9:28 PM Subject: RE: [meteorite-list] Mercury data Hi, Sterling and All, Here's an interesting little article I came across in Nature: http://www.nature.com/nature/journal/v473/n7347/full/nature10092.html http://www.nature.com/nature/journal/v473/n7347/full/nature10092.html Unbound or distant planetary mass population detected by gravitational microlensing I know they've suspected wandering stars in the past, but now planets! If there's these big ones, what's to say there aren't smaller ones? Best, Pete From: sterling_k_w...@sbcglobal.net To: a...@unm.edu; meteorite-list@meteoritecentral.com Date: Sun, 19 Jun 2011 17:59:52 -0500 Subject: Re: [meteorite-list] Mercury data Thanks, Carl. That's was what I was hoping for. There are two Theories of Mercury --- the old one, that Mercury formed from inner disk materials, all iron and refractories, and the new one, that Mercury suffered a Giant Impact' which added its iron to the Mercurian core but blasted Mercury's crust off to be lost. Sometimes the Giant Impact Theory is interpreted as a much-larger Mercury that lost much of its crust to a series of Pretty Dam Big Impacts that contributed no iron but blasted Mercury's crust off to be lost just the same. The old All Iron And Refractories theory seems, at first glance, to be dead, but wait! there's still a heart beat. The Crust is not The Planet. If Mercury has been pasted through the ages by errant asteroids and comets from Out-System that have been tossed down into high eccentricity orbits, that crust of volatiles could be the accretion of 4 billion years of Jupiter's trash toss-out. There's a lot wrong with this idea. It's hard to deliver material to Mercury without splashing it right off into the grip of the Sun's powerful gravity, and it would take a lot of material to pave a planet miles deep. Perhaps the anomalous crust was delivered by the Late Bombardment? Sulfur, visible as yellow swirls, streaks and patches surrounding the pits that burped it, got up and screamed Volatiles! even before those scans were released. It's just like Io, but a lot hotter. It can't accumulate like it does on Io Still, if Mercury is still boiling out sulfur after billions and billions of years, it must have started with a LOT of volatiles. Recent images of Mercury can be found at: http://www.nasa.gov/mission_pages/messenger/multimedia/mercury_images_coll_archive_1.html
