True. Good point. I guess I pictured in my mind a glacier, where sand, rocks and boulders had been pushed and collected over time. In the ice fields of Earth's North and South poles, is there debris like we're talking about?
Maybe the only thing that would be present on Europa's poles is anything that may have fallen from the sky. -----Original Message----- From: Joe Latrell [mailto:joe_latrell@;beyond-earth.com] Sent: Friday, November 01, 2002 12:33 PM To: Europa IcePIC mailing list Subject: RE: Guidance System for Icepick I, and Cryobot thoughts Advanced Note: This only covers a Europa bound probe and not a terrestrial one. Something has really been nagging me and I wanted to throw it out to the group. The assumption up to this point is that ther would be debris to navigate around. Why? Unless physics has changed, ice floats. Why would ice pick up bolders and other various sized rocks if the entire iceflow is sitting on an ocean? I can see small items getting carried away but anything bigger than a pebble is gonna be hard pressed to hang around for the upward journey. Is there anyway to get hold of telemtry from Galileo - and I don't mean the namby pamby stuff NASA has been feeding the public either. Joe Latrell On Fri, 2002-11-01 at 10:41, Christlieb, Scott F. wrote: > > Being unlearned in these things, but really curious........... > > I don't understand how preferential heating or jetting, not that I really > know what these mean, is going to move the vehicle through ice. I'm assuming > that it means specific points of the vehicle will be heated to melting the > ice around it, making room for it to move in a particular direction. Please > correct me if I'm wrong, it wouldn't be the first time. > > I suppose that if we were talking about a clean and pure field ice void of > any debris and the tunnel created were perfectly smooth, the vehicle could > go in any direction using this method. Are we assuming that there is going > to be a minimum of gravel sized, baseball sized, bowling ball sized, large > bolder sized objects and bigger that the vehicle is going to have to either > go through or around? > > Shouldn't we assume the worst, that the ice is a heavy mixture of all the > stuff I mentioned and that as the vehicle makes it's way downward it is not > going to be able to go around it all? Isn't there a high probability that > debris will fall off of the tunnel wall behind and around the vehicle? If > the vehicle gets stuck, how will it move to a new path? > > > Scott - New student of all things Europa > > -----Original Message----- > From: Reeve, Jack W. [mailto:Jack.Reeve@;bakerhughes.com] > Sent: Friday, November 01, 2002 9:56 AM > To: [EMAIL PROTECTED] > Subject: RE: Guidance System for Icepick I, and Cryobot thoughts > > > It's an elegant notion, but articulation is component-intensive and > failure-prone. > > Also, it is most probably unnecessary. Directional control could come via > preferential heating or jetting coupled with an internal inclinometer and a > compass. Just make your preferred path preferentially warmer and you'll go > in that direction. > > An interesting complication of directional guidance on Europa would be that > Europa's magnetic field reverses its position every 5.5 hours. > > Jack > -----Original Message----- > From: Christlieb, Scott F. [mailto:schristlieb@;websmartinteractive.com] > Sent: Friday 01 November 2002 09:32 > To: '[EMAIL PROTECTED]' > Subject: RE: Guidance System for Icepick I, and Cryobot thoughts > > > I was thinking that we could enhance the vehicle's ability to negotiate > changes in direction by giving it a head that swiveled. The ability to bend > in the middle would also be helpful. > > I keep imagining that the Europa Icepick could ultimately take on a > snake-like form. The head would do the driving and the tail would follow > along. > > -----Original Message----- > From: Bruce Moomaw [mailto:moomaw@;cwnet.com] > Sent: Friday, November 01, 2002 4:19 AM > To: Europa Icepick > Subject: Re: Guidance System for Icepick I, and Cryobot thoughts > > > > ----- Original Message ----- > From: [EMAIL PROTECTED] > To: [EMAIL PROTECTED] > Sent: Wednesday, October 30, 2002 7:24 PM > Subject: Guidance System for Icepick I, and Cryobot thoughts > > > 1) reverse course or switch head to tail, and backtrack, along the same > tunnel, > 2) using a hydrogen filled balloon, it could presumeably float back to the > surface. The hydrogen bag might presumeably be stored in the front of the > Europa cryobot. Once the cryobot is prepared to reverse course, the bag > might be filled with hydrogen electolyzed from the local ice. > 3) At that point, the cryobot tail heats up to become the nose, and the > model cuts through the ice, and floats back to the surface, slowly but > surely, on a bag of hydrogen below it. > ____________________ > > Actually, it's a rather intereting one, and the mechanism involved wouldn't > have to be nearly as complex as the one you propose. All you have to do is > arrange for the cryobot, once its descent is complete, to reduce its total > density below that of liquid water -- that is, give it positive buoyancy > like a submarine -- and it would rise to the TOP of any meltwater space it > produced, allowing it to melt its way back up if it had a similar heater on > its top end. This could be done by having it simply drop ballast (perhaps > its lower end?), with the Cryobot having enough low-density internal space > inside its hull (perhaps filled with a lower-density pressure-compensating > liquid) to give it positive buoyancy afterwards. But keep in mind that, > just as it will probably take several years to melt its way down to the > bottom of Europa's ice crust, it will take just as long to melt its way back > up. > > > > == > You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] > Project information and list (un)subscribe info: http://klx.com/europa/ > == > You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] > Project information and list (un)subscribe info: http://klx.com/europa/ > == > You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] > Project information and list (un)subscribe info: http://klx.com/europa/ > == > You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] > Project information and list (un)subscribe info: http://klx.com/europa/ == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/ == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
