Sol System layout in Nemesis Camp

Procyon's family campaign

Moderator: procyon

Re: Sol System layout in Nemesis Camp

Postby procyon on Sat 25 Jun 2011 00:46

Cralis wrote:But I would note that Galileo was sent long before Cassini. And there are 3 more probes being planned for Jupiter, and none for Saturn.


That would be due to the fact that Cassini-Huygens was a very well designed craft. There are no more probes planned because Cassini's mission has been extended twice, the last time to 2017. Why build more if this one is still gathering useful data.

Cralis wrote:Ventilating the heat and insulating the surrounding ice from the base is not that big of a problem. In fact, we do the opposite trying to trap heat with geo-homes now.


That is the problem. Trapping heat is easy. Venting it adequately isn't. I have seen lots of papers on it, but no successful tests. Haven't seen a successful report of sub-surface ice structure able to maintain an internal temp of over 2 C without settling. They always want to sink. Closest to success was closed cell styrofoam. Good insulation and reflectivity. Just crappy constuction value.


Cralis wrote:They aren't so concerned with the ice shifting because it is all trapped in locked plates, they are more concerned with the flexing from the small tidal stresses Europa feels.


Yep. Ever since they measured an oscillation in the elongation of the moon as it passed close to Jupiter, it was considered that the ice was going to be rather fractured and prone to siesmic events.

Cralis wrote:Europa has the advantage of pure liquid water down below and you can drill for it.


What I've read of late would disagree with the pure water issue. It almost certainly has to be salty. Europa induced magnetic field would only be possible with a liquid conductive layer. It might have a liquid iron mantle/layer surrounding a solid iron core but most likely would be a salt water layer. Pure water is a horrible conductor.

Cralis wrote:Surface construction will be much easier, true, but it will also be subject to weather, which may be bad. We still don't have any idea how severe the weather can get there.


True. Titan has weather, and we need more data on it. It looks to be a large Hadley cell, so the whole planet would be a single massive frontal system. Kind of funny to think of a place that cold as using what we consider to be tropical weather dynamics. It has young features, so the weather does cause erosion to the environment. Of course, Europa has almost no atmosphere - but the smoothest surface in the solar system. That could only be due to continual reshaping due to tidal stress. The crust is continually kneeded flat. Probably rough for subsurface builds.

Cralis wrote:Remember that Saturn has belts that do move around, so there is likely to be lots of debris hitting Saturn's belts. While Saturn doesn't suck up as much as Jupiter, it still has a small colony of Lagrange asteroids so it does suck up some.


Not much. At least not like Jupiter. Saturn's a fair bit farther from the main belt, and the absence of its trojan belts is what convinced most folks that Neptune and Uranus did migrate from the inner system to their current locations. With their given orbits they (Neptune mostly) should have stripped Saturn's trojans.

I do have to admit this is one of the most interesting discussions I have had for years. :D
...and I will show you fear in a handful of dust....

Cralis wrote:I would point out that the "what was" which is different from "here and now" can easily change in the "future then."
User avatar
procyon
Sky Marshal
Sky Marshal
 
Posts: 2547
Joined: Mon 26 Apr 2010 16:26
Location: SE IOWA

Re: Sol System layout in Nemesis Camp

Postby Cralis on Sat 25 Jun 2011 01:28

procyon wrote:
Cralis wrote:But I would note that Galileo was sent long before Cassini. And there are 3 more probes being planned for Jupiter, and none for Saturn.


That would be due to the fact that Cassini-Huygens was a very well designed craft. There are no more probes planned because Cassini's mission has been extended twice, the last time to 2017. Why build more if this one is still gathering useful data.


Different purposes. You can't fit all of the experiments and instruments on a single craft. If you look at the Jupiter probes being built, every one of them does something different.

Cralis wrote:Ventilating the heat and insulating the surrounding ice from the base is not that big of a problem. In fact, we do the opposite trying to trap heat with geo-homes now.


That is the problem. Trapping heat is easy. Venting it adequately isn't. I have seen lots of papers on it, but no successful tests. Haven't seen a successful report of sub-surface ice structure able to maintain an internal temp of over 2 C without settling. They always want to sink. Closest to success was closed cell styrofoam. Good insulation and reflectivity. Just crappy constuction value.


True, I've seen lots of papers but nobody wants to go to Antarctica or the North Pole to build one and do some practical research. Tis' that profit thing again. I've actually seen some really fascinating ideas about recycled heat, and some new materials that do stuff never before possible. For example, there is a metal now that converts heat into electricity.

Cralis wrote:They aren't so concerned with the ice shifting because it is all trapped in locked plates, they are more concerned with the flexing from the small tidal stresses Europa feels.


Yep. Ever since they measured an oscillation in the elongation of the moon as it passed close to Jupiter, it was considered that the ice was going to be rather fractured and prone to siesmic events.


Quite possible.

Cralis wrote:Europa has the advantage of pure liquid water down below and you can drill for it.


What I've read of late would disagree with the pure water issue. It almost certainly has to be salty. Europa induced magnetic field would only be possible with a liquid conductive layer. It might have a liquid iron mantle/layer surrounding a solid iron core but most likely would be a salt water layer. Pure water is a horrible conductor.


That is interesting. I seem to recall the Europa didn't have a measurable magnetic field, so that would be news to me. Granted, I haven't been following it quite as closely the last couple years. Earlier proposals suggested that Europa's oceans would have to be fresh water because there was no measurable magnetic field.

Cralis wrote:Surface construction will be much easier, true, but it will also be subject to weather, which may be bad. We still don't have any idea how severe the weather can get there.


True. Titan has weather, and we need more data on it. It looks to be a large Hadley cell, so the whole planet would be a single massive frontal system. Kind of funny to think of a place that cold as using what we consider to be tropical weather dynamics. It has young features, so the weather does cause erosion to the environment.


And that is a major concern, especially with such cold of an environment. Think ice caking to the umpteenth degree.

Of course, Europa has almost no atmosphere - but the smoothest surface in the solar system. That could only be due to continual reshaping due to tidal stress. The crust is continually kneeded flat. Probably rough for subsurface builds.


Last I heard, Europa was estimated to have about 30,000 lbs of Oxygen atmosphere. Not a lot :)

Cralis wrote:Remember that Saturn has belts that do move around, so there is likely to be lots of debris hitting Saturn's belts. While Saturn doesn't suck up as much as Jupiter, it still has a small colony of Lagrange asteroids so it does suck up some.


Not much. At least not like Jupiter. Saturn's a fair bit farther from the main belt, and the absence of its trojan belts is what convinced most folks that Neptune and Uranus did migrate from the inner system to their current locations. With their given orbits they (Neptune mostly) should have stripped Saturn's trojans.


I specifically said "debris" and not "asteroids" because I know there aren't very many real asteroids in the area. However, there seems to be a lot more small debris (especially pebble-to-stone sized debris) of various kinds, than there is nearly anywhere else. (I said nearly...the main belt and kuiper belt are noticeable exceptions.

I do have to admit this is one of the most interesting discussions I have had for years. :D


I don't often have a chance to talk to someone who knows this much about our star system. Where have you been hiding? :lol:
Image
User avatar
Cralis
SDS Member
SDS Member
 
Posts: 11783
Joined: Tue 30 Jun 2009 19:27
Location: Oregon, USA

Re: Sol System layout in Nemesis Camp

Postby procyon on Sat 25 Jun 2011 02:01

Cralis wrote:Different purposes. You can't fit all of the experiments and instruments on a single craft. If you look at the Jupiter probes being built, every one of them does something different.


This is true, but we have gotten a lot of miles from it. The neatest fact lately was that Encladeus has liquid water geyers erupting tons of water daily from (IIRC) its 'southern pole'. This would indicate that it has liquid water within tens of meters of the surface. Quite handy if water on Titan proved to contain contaminants difficult to separate.

Cralis wrote:True, I've seen lots of papers but nobody wants to go to Antarctica or the North Pole to build one and do some practical research. Tis' that profit thing again. I've actually seen some really fascinating ideas about recycled heat, and some new materials that do stuff never before possible. For example, there is a metal now that converts heat into electricity.


If only the almighty $ wasn't so mighty. So much of the work I did had little to do with science and lots to do with profit margins.... :(

Although the metal that converts heat to electricity does open new fields of development in joy buzzers.... :lol:

Cralis wrote:That is interesting. I seem to recall the Europa didn't have a measurable magnetic field, so that would be news to me. Granted, I haven't been following it quite as closely the last couple years. Earlier proposals suggested that Europa's oceans would have to be fresh water because there was no measurable magnetic field.


Galileo was the one that picked up the magnetic signature back in 2003, just before she did her swan dive. She was another long lived little pup.

Cralis wrote:And that is a major concern, especially with such cold of an environment. Think ice caking to the umpteenth degree.


Really, ice (at least water ice) doesn't sublime on Titan, so there is almost no water vapor. Of course a heavy ethane or methane frost/snow/puddle coming in contact with an air leak could be a tad bit uncomfortable.

Cralis wrote:I specifically said "debris" and not "asteroids" because I know there aren't very many real asteroids in the area. However, there seems to be a lot more small debris (especially pebble-to-stone sized debris) of various kinds, than there is nearly anywhere else. (I said nearly...the main belt and kuiper belt are noticeable exceptions.


I was kind of minimizing this one, I will admit. Cassini did pick up evidence that some comet or such hit one of Saturn's moons just recently. At least with its vast atmosphere, Titan shoud burn up most debris.

Cralis wrote:I don't often have a chance to talk to someone who knows this much about our star system. Where have you been hiding?


Sadly enough, the government. At least for a long time. And they don't like to share. This is one of the few areas I can really talk much about. When I signed out 'they' made it abundantly clear that if anyone I was associated with came up with anything remotely connected to any research I was involved in that I would get to share a small cell with a very large man named Bubba who thought I was cute.... :shock:

I really like my wife and kids. Bubba has never appealled to me. :D
...and I will show you fear in a handful of dust....

Cralis wrote:I would point out that the "what was" which is different from "here and now" can easily change in the "future then."
User avatar
procyon
Sky Marshal
Sky Marshal
 
Posts: 2547
Joined: Mon 26 Apr 2010 16:26
Location: SE IOWA

Previous

Return to Nemesis Campaign

Who is online

Users browsing this forum: No registered users and 1 guest