Dynamics of an Earth Ring

Before anybody gives me that look...this question is totally in the
context of a "what if" kind of hypothetical scenario.

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

http://uk.geocities.com/aa_spaceagen...arth-ring.html

My main concern with such a project is one of SAFETY. I'd like to know
what a *safe* perigee (minimum) altitude would be necessary to prevent
orbital decay of ring material. I don't want any material from my
hypothetical ring system coming down toward the Earth under any
circumstances. Would the ring material be contained in a narrow plane
of fixed orbital incline, or would it scatter over time? What about
interactivity with particles trapped in the Van Allen radiation belts?
Is there any learnings from the Voyager studies (and now Cassini
studies) of Saturnian rings that could be used to predict the long
term stability of such a *hypothetical* ring system around the Earth
in the future?

Abdul Ahad

"AA Institute" wrote in message
om...
Before anybody gives me that look...this question is totally in the
context of a "what if" kind of hypothetical scenario.

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

http://uk.geocities.com/aa_spaceagen...arth-ring.html

My main concern with such a project is one of SAFETY. I'd like to know
what a *safe* perigee (minimum) altitude would be necessary to prevent
orbital decay of ring material. I don't want any material from my
hypothetical ring system coming down toward the Earth under any
circumstances. Would the ring material be contained in a narrow plane
of fixed orbital incline, or would it scatter over time? What about
interactivity with particles trapped in the Van Allen radiation belts?
Is there any learnings from the Voyager studies (and now Cassini
studies) of Saturnian rings that could be used to predict the long
term stability of such a *hypothetical* ring system around the Earth
in the future?

Abdul Ahad

I think the moon would prevent the ring from forming properly
Alasdair
--

erect featherless biped
www.digitalmystic.co.uk

"AA Institute" wrote in message
om...
Before anybody gives me that look...this question is totally in the
context of a "what if" kind of hypothetical scenario.

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

http://uk.geocities.com/aa_spaceagen...arth-ring.html

My main concern with such a project is one of SAFETY. I'd like to know
what a *safe* perigee (minimum) altitude would be necessary to prevent
orbital decay of ring material. I don't want any material from my
hypothetical ring system coming down toward the Earth under any
circumstances. Would the ring material be contained in a narrow plane
of fixed orbital incline, or would it scatter over time? What about
interactivity with particles trapped in the Van Allen radiation belts?
Is there any learnings from the Voyager studies (and now Cassini
studies) of Saturnian rings that could be used to predict the long
term stability of such a *hypothetical* ring system around the Earth
in the future?

Why do you want to use missiles to hollow it out?

I suspect that smaller scale engineering would be better in order to
preserve the structure since an asteroid isn't usually large enough for
gravity to glue it together. And then I would be inclined to glue the debris
onto the outside or stuff it into string bags so that I could use it later
if I wanted to move the asteroid.

Stephen

Alasdair ) wrote:



: "AA Institute" wrote in message
: om...
: Before anybody gives me that look...this question is totally in the
: context of a "what if" kind of hypothetical scenario.
:
: Suppose an asteroid somehow, through some super, far future
: engineering achievement has been captured into orbit around the Earth.
: Now suppose we want to carve it out by detonating a series of missiles
: that incrementally hollow their way into the body of such an asteroid.
: The material excavated out of the body would create a thin ring system
: around the Earth, as I try to illustrate he-
:
: http://uk.geocities.com/aa_spaceagen...arth-ring.html
:
: My main concern with such a project is one of SAFETY. I'd like to know
: what a *safe* perigee (minimum) altitude would be necessary to prevent
: orbital decay of ring material. I don't want any material from my
: hypothetical ring system coming down toward the Earth under any
: circumstances. Would the ring material be contained in a narrow plane
: of fixed orbital incline, or would it scatter over time? What about
: interactivity with particles trapped in the Van Allen radiation belts?
: Is there any learnings from the Voyager studies (and now Cassini
: studies) of Saturnian rings that could be used to predict the long
: term stability of such a *hypothetical* ring system around the Earth
: in the future?
:
: Abdul Ahad

: I think the moon would prevent the ring from forming properly

Saturn has several moons and its rings don't seem to mind. I don't doubt
that the moon would have an effect but prevent the forming? No, I don't
believe that.

Eric

: Alasdair
: --

: erect featherless biped
: www.digitalmystic.co.uk

(AA Institute) wrote:

Before anybody gives me that look...

Too late

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
[...]
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

I think the Moon may scupper your plans somewhat. It's friggin' huge
by moon standards, particularly compared to the shepherd moons which
help stabilise Saturn's rings. Just look what it does to the oceans
here on Earth. I doubt a stable ring system is possible for Earth, but
I've not done the calculations (or run the simulations, which is
probably the best way to look at this). Even if it is possible I very,
very much doubt you could create such a ring system in the way you
describe without raining a lot of crud down onto Earth in the process.
Even ignoring the big lumps you would put a massive number of small
particles into a variety of orbits which would make space flight near
the Earth extremely hazardous.

I wouldn't want to be on an orbital space station with some loon
blowing up asteroids around the same planet.


Tim
--
Guns Don't Kill People, Rappers Do.

"Alasdair" . uk wrote in news:cjgn48
:




"AA Institute" wrote in message
om...
Before anybody gives me that look...this question is totally in the
context of a "what if" kind of hypothetical scenario.

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

http://uk.geocities.com/aa_spaceagen...arth-ring.html

My main concern with such a project is one of SAFETY. I'd like to know
what a *safe* perigee (minimum) altitude would be necessary to prevent
orbital decay of ring material. I don't want any material from my
hypothetical ring system coming down toward the Earth under any
circumstances. Would the ring material be contained in a narrow plane
of fixed orbital incline, or would it scatter over time? What about
interactivity with particles trapped in the Van Allen radiation belts?
Is there any learnings from the Voyager studies (and now Cassini
studies) of Saturnian rings that could be used to predict the long
term stability of such a *hypothetical* ring system around the Earth
in the future?

Abdul Ahad

I think the moon would prevent the ring from forming properly
Alasdair

There is currently a ring around earth. If you ever look at a 3-D type
map of satelites, (like J-Track 3D
http://science.nasa.gov/RealTime/JTr.../JTrack3D.html)
you'll see that the satellites in geostationary orbit make a nice ring
around earth :-)

There's a couple gotchas to this statement...first J-Track blows up the
relative size of the dot of light relative to the earth to many, many,
many times the actual size of the spacecraft, so it appears more
populated than it is (true...real rings aren't solid, but this is pushing
it). I heard once jupiter had a very small ring that we only discovered
when we sent probes in close to it...anyone know more info about this?

Also, all these man made satellites have position keeping thrusters, to
compensate for things like the moon. I have no idea as to what would
happen to this "ring" if they suddenly just turned them all off, but I
don't think anything major would happen very fast.

"AA Institute" wrote in message
om...
Before anybody gives me that look...this question is totally in the
context of a "what if" kind of hypothetical scenario.

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

http://uk.geocities.com/aa_spaceagen...arth-ring.html

My main concern with such a project is one of SAFETY. I'd like to know
what a *safe* perigee (minimum) altitude would be necessary to prevent
orbital decay of ring material. I don't want any material from my
hypothetical ring system coming down toward the Earth under any
circumstances. Would the ring material be contained in a narrow plane
of fixed orbital incline, or would it scatter over time? What about
interactivity with particles trapped in the Van Allen radiation belts?
Is there any learnings from the Voyager studies (and now Cassini
studies) of Saturnian rings that could be used to predict the long
term stability of such a *hypothetical* ring system around the Earth
in the future?

Abdul Ahad

I don't need to know any science to suggest you do not do this if you
positively don't want any bits to rain down at all!

Why?

Ever heard of Martian meteorites? Well, the mere fact that we have them
suggests that whenever you start knocking chunks off of celestial bodies,
the things eventually go far and wide.

If you have the tech to capture it, and orbit it, then you probably have the
technology to land it, relatively softly, on the moon, so take it there, and
cut it up at your leisure, whatever you want it for.

Brian

--

Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
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"Tom Kent" wrote in message
. 30.42...
"Alasdair" . uk wrote in news:cjgn48
:




"AA Institute" wrote in message
om...
Before anybody gives me that look...this question is totally in the
context of a "what if" kind of hypothetical scenario.

Suppose an asteroid somehow, through some super, far future
engineering achievement has been captured into orbit around the Earth.
Now suppose we want to carve it out by detonating a series of missiles
that incrementally hollow their way into the body of such an asteroid.
The material excavated out of the body would create a thin ring system
around the Earth, as I try to illustrate he-

http://uk.geocities.com/aa_spaceagen...arth-ring.html

My main concern with such a project is one of SAFETY. I'd like to know
what a *safe* perigee (minimum) altitude would be necessary to prevent
orbital decay of ring material. I don't want any material from my
hypothetical ring system coming down toward the Earth under any
circumstances. Would the ring material be contained in a narrow plane
of fixed orbital incline, or would it scatter over time? What about
interactivity with particles trapped in the Van Allen radiation belts?
Is there any learnings from the Voyager studies (and now Cassini
studies) of Saturnian rings that could be used to predict the long
term stability of such a *hypothetical* ring system around the Earth
in the future?

Abdul Ahad

I think the moon would prevent the ring from forming properly
Alasdair

There is currently a ring around earth. If you ever look at a 3-D type
map of satelites, (like J-Track 3D
http://science.nasa.gov/RealTime/JTr.../JTrack3D.html)
you'll see that the satellites in geostationary orbit make a nice ring
around earth :-)

There's a couple gotchas to this statement...first J-Track blows up the
relative size of the dot of light relative to the earth to many, many,
many times the actual size of the spacecraft, so it appears more
populated than it is (true...real rings aren't solid, but this is pushing
it). I heard once jupiter had a very small ring that we only discovered
when we sent probes in close to it...anyone know more info about this?

Also, all these man made satellites have position keeping thrusters, to
compensate for things like the moon. I have no idea as to what would
happen to this "ring" if they suddenly just turned them all off, but I
don't think anything major would happen very fast.


I had no idea that there were that many satellites up there, that is
amazing!
I agree with brian gaff don't blow em up - land and mine them

Alasdair

--

erect featherless biped
www.digitalmystic.co.uk

Tom Kent wrote:

Also, all these man made satellites have position keeping thrusters, to
compensate for things like the moon. I have no idea as to what would
happen to this "ring" if they suddenly just turned them all off, but I
don't think anything major would happen very fast.

There's a natural tendency for things in geosynchronous orbit to collect
at one specific spot, due to the moon's influence. I don't know how
quickly that effect would act, though.

"Steve Maudsley" wrote in message

Why do you want to use missiles to hollow it out?

Bearing in mind that most asteroids are quite dense, often with some
metallic composition, then some heavy blasting will be necessary to
get fairly rapid results.

I just realised there is a problem with this idea, missile impacts
would leave the hole radioactive. But if post detonation radioactivity
only affects the asteroid's inner walls down to a few inches in depth,
then small scale robotic diggers which excavate a few inches of rock
all the way around the interior of the hole and then blowing them out
of the hole with perhaps compressed air, could eliminate the
radioactiveness. RATs (rock abrasion tools) on the Mars rovers do
something similar today.

I suspect that smaller scale engineering would be better in order to
preserve the structure since an asteroid isn't usually large enough for
gravity to glue it together. And then I would be inclined to glue the debris
onto the outside or stuff it into string bags so that I could use it later
if I wanted to move the asteroid.

Good idea, but this calls for another level of robotic articulation.
Perhaps a fly around robot with a vacuum cleaner style of suction
mechanism, pulling stuff into heavy duty plastic bags could do the
trick.

So there is a way round the ring problem...

AAI