Small Asteroids Are Held Together by Van Der Waals Forces
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From: Mike Jr on 17 Feb 2010 14:16 "Astronomers have known for some time that the forces involved [to hold small asteroids together] do not need to be large: various simulations have shown that even small cohesive forces can make spinning piles of rubble stable in low gravity environments. Of the various possibilities, the main ones that astronomers have studied are radiation pressure from the Sun, friction and electrostatic forces between ionised dust (which is responsible for dust levitation on the Moon and so more likely to push dust apart). The goal of the latest work by Scheeres and co is to "perform a survey of the known relevant forces that act on grains and particles, state their analytical form and relevant constants for the space environment, and consider how these forces scale relative to each other." Scheeres and co show that none of the usual suspects is the likely culprit. Instead it looks as if small asteroids are held together by van der Waals forces. " http://technologyreview.com/blog/arxiv/24818/ --Mike Jr.
From: bert on 17 Feb 2010 14:51 On Feb 17, 2:16 pm, Mike Jr <n00s...(a)comcast.net> wrote: > "Astronomers have known for some time that the forces involved [to > hold small asteroids together] do not need to be large: various > simulations have shown that even small cohesive forces can make > spinning piles of rubble stable in low gravity environments. > > Of the various possibilities, the main ones that astronomers have > studied are radiation pressure from the Sun, friction and > electrostatic forces between ionised dust (which is responsible for > dust levitation on the Moon and so more likely to push dust apart). > > The goal of the latest work by Scheeres and co is to "perform a survey > of the known relevant forces that act on grains and particles, state > their analytical form and relevant constants for the space > environment, and consider how these forces scale relative to each > other." > > Scheeres and co show that none of the usual suspects is the likely > culprit. Instead it looks as if small asteroids are held together by > van der Waals forces. " > > http://technologyreview.com/blog/arxiv/24818/ > > --Mike Jr. Asteroids,comets.and dust particles relate to super nova explosion that pushed them into nebula clouds. Lots to think about.Big question why this dust did not end up to create havac in stopping fusion in cores of stars??? This has been fudged by imperial thinkers but not by me. TreBert
From: BURT on 18 Feb 2010 00:55 On Feb 17, 11:51 am, bert <herbertglazie...(a)msn.com> wrote: > On Feb 17, 2:16 pm, Mike Jr <n00s...(a)comcast.net> wrote: > > > > > > > "Astronomers have known for some time that the forces involved [to > > hold small asteroids together] do not need to be large: various > > simulations have shown that even small cohesive forces can make > > spinning piles of rubble stable in low gravity environments. > > > Of the various possibilities, the main ones that astronomers have > > studied are radiation pressure from the Sun, friction and > > electrostatic forces between ionised dust (which is responsible for > > dust levitation on the Moon and so more likely to push dust apart). > > > The goal of the latest work by Scheeres and co is to "perform a survey > > of the known relevant forces that act on grains and particles, state > > their analytical form and relevant constants for the space > > environment, and consider how these forces scale relative to each > > other." > > > Scheeres and co show that none of the usual suspects is the likely > > culprit. Instead it looks as if small asteroids are held together by > > van der Waals forces. " > > >http://technologyreview.com/blog/arxiv/24818/ > > > --Mike Jr. > > Asteroids,comets.and dust particles relate to super nova explosion > that pushed them into nebula clouds. Lots to think about.Big question > why this dust did not end up to create havac in stopping fusion in > cores of stars??? This has been fudged by imperial thinkers but not > by me. TreBert- Hide quoted text - > > - Show quoted text - The universe is 44 billion years old as the most distant things expanded with space-distance slower than light. They took longer to get to their 13.7 light year distance. Anf for their light to travel through expanding new space-distance to us. Mitch Raemsch
From: BURT on 18 Feb 2010 01:03 On Feb 17, 11:51 am, bert <herbertglazie...(a)msn.com> wrote: > On Feb 17, 2:16 pm, Mike Jr <n00s...(a)comcast.net> wrote: > > > > > > > "Astronomers have known for some time that the forces involved [to > > hold small asteroids together] do not need to be large: various > > simulations have shown that even small cohesive forces can make > > spinning piles of rubble stable in low gravity environments. > > > Of the various possibilities, the main ones that astronomers have > > studied are radiation pressure from the Sun, friction and > > electrostatic forces between ionised dust (which is responsible for > > dust levitation on the Moon and so more likely to push dust apart). > > > The goal of the latest work by Scheeres and co is to "perform a survey > > of the known relevant forces that act on grains and particles, state > > their analytical form and relevant constants for the space > > environment, and consider how these forces scale relative to each > > other." > > > Scheeres and co show that none of the usual suspects is the likely > > culprit. Instead it looks as if small asteroids are held together by > > van der Waals forces. " > > >http://technologyreview.com/blog/arxiv/24818/ > > > --Mike Jr. > > Asteroids,comets.and dust particles relate to super nova explosion > that pushed them into nebula clouds. Lots to think about.Big question > why this dust did not end up to create havac in stopping fusion in > cores of stars??? This has been fudged by imperial thinkers but not > by me. TreBert- Hide quoted text - > > - Show quoted text - Why is there a failed planet? Mitch Raemsch
From: BURT on 18 Feb 2010 01:14
On Feb 17, 11:51 am, bert <herbertglazie...(a)msn.com> wrote: > On Feb 17, 2:16 pm, Mike Jr <n00s...(a)comcast.net> wrote: > > > > > > > "Astronomers have known for some time that the forces involved [to > > hold small asteroids together] do not need to be large: various > > simulations have shown that even small cohesive forces can make > > spinning piles of rubble stable in low gravity environments. > > > Of the various possibilities, the main ones that astronomers have > > studied are radiation pressure from the Sun, friction and > > electrostatic forces between ionised dust (which is responsible for > > dust levitation on the Moon and so more likely to push dust apart). > > > The goal of the latest work by Scheeres and co is to "perform a survey > > of the known relevant forces that act on grains and particles, state > > their analytical form and relevant constants for the space > > environment, and consider how these forces scale relative to each > > other." > > > Scheeres and co show that none of the usual suspects is the likely > > culprit. Instead it looks as if small asteroids are held together by > > van der Waals forces. " > > >http://technologyreview.com/blog/arxiv/24818/ > > > --Mike Jr. > > Asteroids,comets.and dust particles relate to super nova explosion > that pushed them into nebula clouds. Lots to think about.Big question > why this dust did not end up to create havac in stopping fusion in > cores of stars??? This has been fudged by imperial thinkers but not > by me. TreBert- Hide quoted text - > > - Show quoted text - How do individual elements find themselves together in the form of deposits? Why do they hang around each other in order? Mitch Raemsch |