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risky path for cassini probe?
the cassini probe is going to pass between the F and G rings,
this will no doubt bring some fantastic imaging opportunities but isnt it a little risky? whats the chances of an impact? im sure Nasa have done their home work but even so some risk must be there. I believe the voyager was to pass through the rings but they decided aganst it for the same reason im not sure where abouts though. Simon |
#2
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"simon.coombs3" wrote:
sc the cassini probe is going to pass between the F and G rings, sc this will no doubt bring some fantastic imaging opportunities but sc isnt it a little risky? whats the chances of an impact? im sure Nasa sc have done their home work but even so some risk must be there. Yes, there is some risk, which is why Cassini's high gain antenna will be pointed in the ram (forward) direction during both crossings of the ring plane in order to provide some degree of shielding from ring particles. sc I believe the voyager was to pass through the rings but sc they decided aganst it for the same reason im not sure sc where abouts though. Pioneer 11 and Voyager 2 passed through the rings successfully. |
#3
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In message , Ed
writes "simon.coombs3" wrote: sc the cassini probe is going to pass between the F and G rings, sc this will no doubt bring some fantastic imaging opportunities but sc isnt it a little risky? whats the chances of an impact? im sure Nasa sc have done their home work but even so some risk must be there. Yes, there is some risk, which is why Cassini's high gain antenna will be pointed in the ram (forward) direction during both crossings of the ring plane in order to provide some degree of shielding from ring particles. sc I believe the voyager was to pass through the rings but sc they decided aganst it for the same reason im not sure sc where abouts though. Pioneer 11 and Voyager 2 passed through the rings successfully. No and no. (but the information produced by those craft presumably gives them the confidence to aim Cassini through the gap) I can document the date when Pioneer 11 was aimed outside (May 1978, according to "Solar System Log") but not Voyager 2. -- What have they got to hide? Release the full Beagle 2 report. Remove spam and invalid from address to reply. |
#4
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"Jonathan Silverlight" wrote:
E Pioneer 11 and Voyager 2 passed through the rings E successfully. JS No and no. (but the information produced by those craft presumably JS gives them the confidence to aim Cassini through the gap) JS I can document the date when Pioneer 11 was aimed outside (May JS 1978, according to "Solar System Log") but not Voyager 2. Well, my source (David Harland's book, "Mission to Saturn") states: "...as Voyager 2 crossed the ring plane, it was surrounded by a cloud of plasma, and had to correct its orientation, due to thousands of micron- sized grains in the G-ring hitting the spacecraft." Here's another reference, an on-line article from SSI which also confirms Voyager 2's flight through the G-ring: http://tinyurl.com/3gdcb (PDF from Spacescience.org) |
#5
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In message , Ed
writes "Jonathan Silverlight" wrote: E Pioneer 11 and Voyager 2 passed through the rings E successfully. JS No and no. (but the information produced by those craft presumably JS gives them the confidence to aim Cassini through the gap) JS I can document the date when Pioneer 11 was aimed outside (May JS 1978, according to "Solar System Log") but not Voyager 2. Well, my source (David Harland's book, "Mission to Saturn") states: "...as Voyager 2 crossed the ring plane, it was surrounded by a cloud of plasma, and had to correct its orientation, due to thousands of micron- sized grains in the G-ring hitting the spacecraft." Here's another reference, an on-line article from SSI which also confirms Voyager 2's flight through the G-ring: http://tinyurl.com/3gdcb (PDF from Spacescience.org) Woops! Thanks for the correction. Looking at "The Far Planets" (the first book that came to hand) I read that Voyager 2 had "a series of unexpected thruster firings" implying some force hitting the spacecraft. |
#6
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"simon.coombs3" wrote in message ...
the cassini probe is going to pass between the F and G rings, this will no doubt bring some fantastic imaging opportunities but isnt it a little risky? whats the chances of an impact? im sure Nasa have done their home work but even so some risk must be there. The initial capture orbit around Saturn seems to have been achieved with success (sigh of relief...). I don't know the full shape, size and orientation of Cassini's orbital ellipse post SOI, but surely similar risks will apply each and every time the probe passes through periapsis (closest point to Saturn and the rings in its orbit) throughout its mission from here on? Presumably NASA will be firing successive burns to fine-tune the orbit going forward, but anyone know where I can get a diagram / some facts and figs on the basic current/intended orbit? Thanks. Abdul Ahad http://uk.geocities.com/aa_spaceagent/astronomy.html I believe the voyager was to pass through the rings but they decided aganst it for the same reason im not sure where abouts though. Simon |
#7
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Abdul Ahad wrote:
"simon.coombs3" wrote in message ... the cassini probe is going to pass between the F and G rings, this will no doubt bring some fantastic imaging opportunities but isnt it a little risky? whats the chances of an impact? im sure Nasa have done their home work but even so some risk must be there. The initial capture orbit around Saturn seems to have been achieved with success (sigh of relief...). I don't know the full shape, size and orientation of Cassini's orbital ellipse post SOI, but surely similar risks will apply each and every time the probe passes through periapsis (closest point to Saturn and the rings in its orbit) throughout its mission from here on? Presumably NASA will be firing successive burns to fine-tune the orbit going forward, but anyone know where I can get a diagram / some facts and figs on the basic current/intended orbit? Thanks. Abdul Ahad http://uk.geocities.com/aa_spaceagent/astronomy.html I believe the voyager was to pass through the rings but they decided aganst it for the same reason im not sure where abouts though. Simon http://saturn.jpl.nasa.gov/operation...aturn-tour.cfm -- Mike Collins UK Mike&heather-at-oakwellmount-dot-freeserve-dot-co-dot-uk |
#8
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Sorry pasted the link twice
http://saturn.jpl.nasa.gov/operations/saturn-tour.cfm -- Mike Collins UK Mike&heather-at-oakwellmount-dot-freeserve-dot-co-dot-uk |
#9
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In om,
Abdul Ahad typed: Presumably NASA will be firing successive burns to fine-tune the orbit going forward, but anyone know where I can get a diagram / some facts and figs on the basic current/intended orbit? Thanks. Abdul, http://www.esa.int/SPECIALS/Cassini-...6E2VQUD_0.html For a fascinating animated diagram. Jo |
#10
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well, as per nasa news letter 680 impacts per second recorded during the
pass through..........all very small particles and no damage. "Mike Collins" wrote in message ... Sorry pasted the link twice http://saturn.jpl.nasa.gov/operations/saturn-tour.cfm -- Mike Collins UK Mike&heather-at-oakwellmount-dot-freeserve-dot-co-dot-uk |
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