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Are Space Flights Always Limited to the Solar System Plane?

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  Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-13 18:45 +0000
    Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-13 21:18 +0200
    Re: Are Space Flights Always Limited to the Solar System Plane? Mahipal <mahipal7638@gmail.com> - 2017-07-13 13:32 -0700
      Re: Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-13 21:15 +0000
        Re: Are Space Flights Always Limited to the Solar System Plane? Serg io <invaalid@invalid.com> - 2017-07-13 16:22 -0500
          Re: Are Space Flights Always Limited to the Solar System Plane? Serg io <invaalid@invalid.com> - 2017-07-13 16:33 -0500
            Re: Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-14 00:14 +0000
              Re: Are Space Flights Always Limited to the Solar System Plane? Serg io <invaalid@invalid.com> - 2017-07-13 19:46 -0500
              Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-14 07:30 +0200
                Re: Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-14 09:03 +0000
                  Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-14 12:21 +0200
              Re: Are Space Flights Always Limited to the Solar System Plane? Wally W. <ww84wa@aim.com> - 2017-07-14 08:10 -0400
                Re: Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-14 23:14 +0000
                  Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-15 11:04 +0200
                    Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-15 11:23 +0200
                      Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-15 13:34 +0200
                        Re: Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-15 12:55 +0000
                          Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-15 15:18 +0200
                          Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-15 16:14 +0200
        Re: Are Space Flights Always Limited to the Solar System Plane? Mahipal <mahipal7638@gmail.com> - 2017-07-13 19:26 -0700
          Re: Are Space Flights Always Limited to the Solar System Plane? "F. Russell" <fr@random.info> - 2017-07-14 09:11 +0000
            Re: Are Space Flights Always Limited to the Solar System Plane? Mahipal <mahipal7638@gmail.com> - 2017-07-14 04:09 -0700
              Re: Are Space Flights Always Limited to the Solar System Plane? Edward Prochak <edprochak@gmail.com> - 2017-07-14 05:22 -0700
                Re: Are Space Flights Always Limited to the Solar System Plane? Mahipal <mahipal7638@gmail.com> - 2017-07-14 06:33 -0700
              Re: Are Space Flights Always Limited to the Solar System Plane? fr314159@gmail.com - 2017-07-14 07:30 -0700
                Re: Are Space Flights Always Limited to the Solar System Plane? Mahipal <mahipal7638@gmail.com> - 2017-07-14 08:05 -0700
                  Re: Are Space Flights Always Limited to the Solar System Plane? Serg io <invaalid@invalid.com> - 2017-07-14 11:50 -0500
        Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-14 06:43 +0200
    Re: Are Space Flights Always Limited to the Solar System Plane? "Dave" <dave1981@hotmail.com> - 2017-07-15 07:10 -0700
      Re: Are Space Flights Always Limited to the Solar System Plane? Poutnik <poutnik4nntp@gmail.com> - 2017-07-15 16:18 +0200
    Re: Are Space Flights Always Limited to the Solar System Plane? "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-07-15 13:56 -0700
      Re: Are Space Flights Always Limited to the Solar System Plane? "hanson" <hanson@quick.net> - 2017-07-15 17:16 -0700

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#640347 — Are Space Flights Always Limited to the Solar System Plane?

A spacecraft launched from earth will have a velocity component equal to
the earth's orbital velocity around the sun (30 km/sec).

To place this spacecraft in an orbit perpendicular to the plane of the
solar system would require that this velocity component be overcome.  This
would require a LOT of fuel and it seems that for this reason such a
perpendicular orbit would be unfeasible.

Is this correct?  Are all spacecraft then limited practically to orbits
that are within the plane of the solar system?

A separate question would be the reason why an orbit perpendicular to the
solar system plane would be useful.

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#640355

Dne 13/07/2017 v 20:45 F. Russell napsal(a):
> A spacecraft launched from earth will have a velocity component equal to
> the earth's orbital velocity around the sun (30 km/sec).
> 
> To place this spacecraft in an orbit perpendicular to the plane of the
> solar system would require that this velocity component be overcome.  This
> would require a LOT of fuel and it seems that for this reason such a
> perpendicular orbit would be unfeasible.
> 
> Is this correct?  Are all spacecraft then limited practically to orbits
> that are within the plane of the solar system?
> 
> A separate question would be the reason why an orbit perpendicular to the
> solar system plane would be useful.
> 

Between 2 extremes
   of the orbit in the ecliptic plane
   and the orbit perpendicular to the ecliptixc plane,

there is a wide range of tilted orbits.

For addition of orbital momentum projection on one axis,
there is no need to cancel the projection on other axis.

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640361

On Thursday, July 13, 2017 at 2:43:00 PM UTC-4, F. Russell wrote:
> A spacecraft launched from earth will have a velocity component equal to
> the earth's orbital velocity around the sun (30 km/sec).

The Solar System Plane is a mathematical useful abstraction. There are
many such planes. Ecliptic plane, galactic plane, and a bazillion^3 other ones. 
Look up Celestial Sphere to begin getting oriented in The Universe.

> To place this spacecraft in an orbit perpendicular to the plane of the
> solar system would require that this velocity component be overcome.  This
> would require a LOT of fuel and it seems that for this reason such a
> perpendicular orbit would be unfeasible.

The question is irrelevant with respect to fuel usage/required. So
ignore it for a while. It's a practical question, but need not apply.

> Is this correct?  Are all spacecraft then limited practically to orbits
> that are within the plane of the solar system?

No. There are GEO, LEO, ..., and polar orbits for spacecraft. Remember
the Irridium project of providing communications all the Earth over?
 
> A separate question would be the reason why an orbit perpendicular to the
> solar system plane would be useful.

How thick do you think a mathematical plane is? It's zero. Period.

http://www.springer.com/us/book/9789027712042 Spacecraft Attitude
Determination and Control edited by Wertz, James R. is a mandatory
book worth reading/studying for rocket scientists. It's a collection
of articles by many different physicists on various aspects of space
flight. Great book! Highly mathematical, very advanced. Incredibly useful!

Within this book, you'll find lots of references! Will keep you busy
for years! I'm sure there's a Russian or Chinese pdf you can download
for free. I've got a couple of Wertz's books in me m(y) collection. 

-- Mahipal “IPMM... माहिपाल ७६३८: d(me) != 0 ... me alwa(y)s changes... Enjo(y)!”  
Enjo(y)... Salute… Cheers... Open your M I N D… Time it is Is IS 3PM somePlace. 

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#640369

On Thu, 13 Jul 2017 13:32:16 -0700, Mahipal wrote:

> 
> No. There are GEO, LEO, ..., and polar orbits for spacecraft. Remember
> the Irridium project of providing communications all the Earth over?
>  

I'm not referring to earth orbiting spacecraft.  I am interested in
interplanetary spacecraft that travel well beyond the vicinity of
the earth.

AFAIK, there are no such spacecraft in orbits perpendicular to the
ecliptic plane.  Even the Pioneer and Voyager missions, both of which
are now far beyond the orbit of Pluto, are approximately within the
ecliptic plane.

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#640371

On 7/13/2017 4:15 PM, F. Russell wrote:
> On Thu, 13 Jul 2017 13:32:16 -0700, Mahipal wrote:
> 
>>
>> No. There are GEO, LEO, ..., and polar orbits for spacecraft. Remember
>> the Irridium project of providing communications all the Earth over?
>>   
> 
> I'm not referring to earth orbiting spacecraft.  I am interested in
> interplanetary spacecraft that travel well beyond the vicinity of
> the earth.
> 
> AFAIK, there are no such spacecraft in orbits perpendicular to the
> ecliptic plane.  Even the Pioneer and Voyager missions, both of which
> are now far beyond the orbit of Pluto, are approximately within the
> ecliptic plane.
> 

not true, they can slingshot up/down using another planets gravity
I think they did that 20 years ago.

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#640372

On 7/13/2017 4:22 PM, Serg io wrote:
> On 7/13/2017 4:15 PM, F. Russell wrote:
>> On Thu, 13 Jul 2017 13:32:16 -0700, Mahipal wrote:
>>
>>>
>>> No. There are GEO, LEO, ..., and polar orbits for spacecraft. Remember
>>> the Irridium project of providing communications all the Earth over?
>>
>> I'm not referring to earth orbiting spacecraft.  I am interested in
>> interplanetary spacecraft that travel well beyond the vicinity of
>> the earth.
>>
>> AFAIK, there are no such spacecraft in orbits perpendicular to the
>> ecliptic plane.  Even the Pioneer and Voyager missions, both of which
>> are now far beyond the orbit of Pluto, are approximately within the
>> ecliptic plane.
>>
> 
> not true, they can slingshot up/down using another planets gravity
> I think they did that 20 years ago.
> 

lots of transfer of orbit stuff here;

http://ccar.colorado.edu/asen5050/projects/projects_2012/reid/


Ulysses was one

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#640382

On Thu, 13 Jul 2017 16:33:57 -0500, Serg io wrote:

> 
> lots of transfer of orbit stuff here;
> 
> http://ccar.colorado.edu/asen5050/projects/projects_2012/reid/
> 
> 
> Ulysses was one
>

Ulysses was indeed a "weird" mission.  To orbit the sun the spacecraft
needed to first be sent to Jupiter!  The solar orbit has it's aphelion
at Jupiter!

The web site gives the story:

"Direct injection into a solar polar orbit from the Earth is not feasible,
because the energy required cannot be provided even by the most powerful
launch vehicles available today. The energy needed is so much, because the
Earth itself orbits the Sun at a speed of 30 kms-1 in a plane perpendicular
to the desired solar polar orbit and the energy imparted to a space probe
must cancel out this motion in addition to providing the correct polar trajectory...
A polar orbit around the Sun can be achieved, however, by taking advantage of
a gravity assist by another planet..."

http://sci.esa.int/ulysses/31043-orbit-navigation

It seems that a direct polar orbit around the sun, with both aphelion and
perihelion within the orbit of planet Mercury, would be practically impossible.

I wonder if pre-positioning large stocks of fuel in space, followed by
docking procedures after spacecraft launch, could ever accomplish the goal.

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#640388

On 7/13/2017 7:14 PM, F. Russell wrote:
> On Thu, 13 Jul 2017 16:33:57 -0500, Serg io wrote:
> 
>>
>> lots of transfer of orbit stuff here;
>>
>> http://ccar.colorado.edu/asen5050/projects/projects_2012/reid/
>>
>>
>> Ulysses was one
>>
> 
> Ulysses was indeed a "weird" mission.  To orbit the sun the spacecraft
> needed to first be sent to Jupiter!  The solar orbit has it's aphelion
> at Jupiter!
> 
> The web site gives the story:
> 
> "Direct injection into a solar polar orbit from the Earth is not feasible,
> because the energy required cannot be provided even by the most powerful
> launch vehicles available today. The energy needed is so much, because the
> Earth itself orbits the Sun at a speed of 30 kms-1 in a plane perpendicular
> to the desired solar polar orbit and the energy imparted to a space probe
> must cancel out this motion in addition to providing the correct polar trajectory...
> A polar orbit around the Sun can be achieved, however, by taking advantage of
> a gravity assist by another planet..."
> 
> http://sci.esa.int/ulysses/31043-orbit-navigation
> 
> It seems that a direct polar orbit around the sun, with both aphelion and
> perihelion within the orbit of planet Mercury, would be practically impossible.
> 
> I wonder if pre-positioning large stocks of fuel in space, followed by
> docking procedures after spacecraft launch, could ever accomplish the goal.
> 

It would probably take too much energy to keep the large stocks of fuel 
in a specific location in space, and you would have to slow down the 
30km/sec initial velocity somehow.  Jupiter is the best shot,

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#640415

Dne 14/07/2017 v 02:14 F. Russell napsal(a):
> 
> Ulysses was indeed a "weird" mission.  To orbit the sun the spacecraft
> needed to first be sent to Jupiter!  The solar orbit has it's aphelion
> at Jupiter!

Why weird ? It is logical. Jupiter is the best source
for gaining the angular momentum perpendicular to the ecliptic axis.

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640434

On Fri, 14 Jul 2017 07:30:16 +0200, Poutnik wrote:

> 
> Why weird ? It is logical. 
>

Logical?  Why take SIX YEARS to complete an orbit when
it should require less than one year?

Why sail completely around South America when one can
dig the Panama Canal?

Such methods are the mark of a seriously underfunded and
desperate agency -- and that describes NASA.

The only problem is the cost of launching enough fuel
into space.  Instead of a single rocket launch, several
prior launches could be used to place sufficient fuel
into earth orbit.  Then the spacecraft could link up
with the pre-positioned fuel and use it to achieve a
direct polar orbit around the sun.

How many scientists or engineers on the Ulysses project
actually died before the mission total of three solar
orbits was completed?

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#640436

Dne 14.7.2017 v 11:03 F. Russell napsal(a):
> On Fri, 14 Jul 2017 07:30:16 +0200, Poutnik wrote:
> 
>>
>> Why weird ? It is logical.
>>
> 
> Logical?  Why take SIX YEARS to complete an orbit when
> it should require less than one year?
> 
> Why sail completely around South America when one can
> dig the Panama Canal?

Because digging the Panama Canal caused bankrupt of company
and huge number of casualties.

Shortest ways are not always the easiest.

Why sail ships preferred travelling to Pacific
not around the Cap Horn to the west,
but to the east around Africa,
Indian ocean, around Singapur and Sulu sea ?

> 
> Such methods are the mark of a seriously underfunded and
> desperate agency -- and that describes NASA.

They are the mark of a seriously thought options,
taking into account the total cost and technical challenges.
> 
> The only problem is the cost of launching enough fuel
> into space.  Instead of a single rocket launch, several
> prior launches could be used to place sufficient fuel
> into earth orbit.  Then the spacecraft could link up
> with the pre-positioned fuel and use it to achieve a
> direct polar orbit around the sun.

This is mark of a serious underestimation of problems.

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640440

On 14 Jul 2017 00:14:31 GMT, F. Russell wrote:

>On Thu, 13 Jul 2017 16:33:57 -0500, Serg io wrote:
>
>> 
>> lots of transfer of orbit stuff here;
>> 
>> http://ccar.colorado.edu/asen5050/projects/projects_2012/reid/
>> 
>> 
>> Ulysses was one
>>
>
>Ulysses was indeed a "weird" mission.  To orbit the sun the spacecraft
>needed to first be sent to Jupiter!  The solar orbit has it's aphelion
>at Jupiter!
>
>The web site gives the story:
>
>"Direct injection into a solar polar orbit from the Earth is not feasible,
>because the energy required cannot be provided even by the most powerful
>launch vehicles available today. The energy needed is so much, because the
>Earth itself orbits the Sun at a speed of 30 kms-1 in a plane perpendicular
>to the desired solar polar orbit and the energy imparted to a space probe
>must cancel out this motion in addition to providing the correct polar trajectory...
>A polar orbit around the Sun can be achieved, however, by taking advantage of
>a gravity assist by another planet..."
>
>http://sci.esa.int/ulysses/31043-orbit-navigation
>
>It seems that a direct polar orbit around the sun, with both aphelion and
>perihelion within the orbit of planet Mercury, would be practically impossible.
>
>I wonder if pre-positioning large stocks of fuel in space, followed by
>docking procedures after spacecraft launch, could ever accomplish the goal.

It isn't a "goal" without an answer to the second question in your OP:

> A separate question would be the reason why an orbit 
> perpendicular to the solar system plane would be useful.

Why did Ulysses do it?

Did the results live up to expectations?

Why do you have a "goal" of doing it again?

Recall the "goal" of going to the moon. "We" (I saw it on TV, with
Uncle Walter telling lies about why it was important) went there.
Based on what was found, we haven't come up with a reason -- in the
40+ years since "our" last trip there -- why anyone should go back.

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#640539

On Fri, 14 Jul 2017 08:10:07 -0400, Wally W. wrote:

> 
> Why do you have a "goal" of doing it again?
> 

I have no goal.  I am merely speculating on how it could
be done if it ever became a goal.

How much fuel would it require to cancel a 30km/sec velocity
component?






>
> Recall the "goal" of going to the moon...
> we haven't come up with a reason -- in the 40+ years since "our"
> last trip there -- why anyone should go back.
>

Sending humans (Americans) to the moon was motivated in large
part by the need to assert the supremacy of capitalism over
communism.  Back then the entire world was split into "free"
and communist factions.

The Soviets did similar propagandizing with Sputnik and Gagarin.

But the moon missions were very valuable scientifically.

Also, taxpayer dollars are still being spent to make future moon
missions more successful.  The NASA GRAIL satellite has mapped
the gravity field of the moon in very fine detail to make navigation
easier for future lunar landings.  The Chinese or the Indians will
certainly use this free data for their own lunar missions.

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#640602

Dne 15/07/2017 v 01:14 F. Russell napsal(a):
> On Fri, 14 Jul 2017 08:10:07 -0400, Wally W. wrote:
> 
>>
>> Why do you have a "goal" of doing it again?
>>
> 
> I have no goal.  I am merely speculating on how it could
> be done if it ever became a goal.
> 
> How much fuel would it require to cancel a 30km/sec velocity
> component?
> 
See the Ciolkovski equation [1]

 delta_v = v_e * ln ( m0 / m1 )

delta_v is speed difference
v_e is the rocket engine nozzle gas speed
m0, m1 are anitial and final rocker ( stage ) mass.

Nozzle speed is typically 2-3 km/s [2]

For 1 stage rocket,
For v_e= 3 km/s , 30 km/s difference and 10 ton of total final mass,
( useful cargo would be much less )
we need. 10 * exp ( 30/3) = 220 000 tons.

For 2 or 3 stage, it would be better, but not dramatically.

For comparison, Saturn V, used in the Apollo program,
had about 3 000 tons.[3].

Not funny. :-)

[1] https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation
[2] https://en.wikipedia.org/wiki/Rocket_engine_nozzle
[3] https://cs.wikipedia.org/wiki/Saturn_V

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640603

Dne 15/07/2017 v 11:04 Poutnik napsal(a):
> See the Ciolkovski equation [1]
> 
>  delta_v = v_e * ln ( m0 / m1 )
> 
> [...]
> 
> For 1 stage rocket,
> For v_e= 3 km/s , 30 km/s difference and 10 ton of total final mass,
> ( useful cargo would be much less )
> we need. 10 * exp ( 30/3) = 220 000 tons.
> 
> For 2 or 3 stage, it would be better, but not dramatically.
> 
> For comparison, Saturn V, used in the Apollo program,
> had about 3 000 tons.[3].
> 
Let suppose 3 stage rocket with estimated mass ratios

10% of mass is the next stage or final cargo modul.
15% of mass is the stage construction mass.
75% of mass is the stage fuel mass.
( real numbers differ )

the total mass, with 10 ton final cargo modul,
would be 10 000 ton, more than 3 times Saturn V

m0/m1 will be always the same 100/25 = 4.0
ln 4.0 = cca 1.4

delta_v for each stage will be 3 * 1.4 = 4.2 km/s
Total delta_v will be 3 * 4.2 = 12.6 km/s

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640611

Dne 15/07/2017 v 11:23 Poutnik napsal(a):

If used more realistic value for the mass ratio 1 : 15 [1]
and the state of art nozzle speed 4.5 km/s
for bi-component liquid fuel.....

10% of mass is the next stage or final cargo modul.
6 % of mass is the stage construction mass.
84% of mass is the stage fuel mass. ( mas ratio 1 : 15 = 6 : 90 )

the total mass, with 3 ton final cargo modul,
( with useful mass much less )

total mass would be 3 000 ton, about the Saturn V

m0/m1 will be always the same 100/16 = cca 7.14
ln 7.14 = cca 1.97

delta_v for each stage will be 4.5 * 1.97 = cca 8.9 km/s
Total delta_v will be 3 * 8.9 = 26.7 km/s

[1] https://en.wikipedia.org/wiki/Mass_ratio

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640616

On Sat, 15 Jul 2017 13:34:56 +0200, Poutnik wrote:

>
> and the state of art nozzle speed 4.5 km/s
> for bi-component liquid fuel.....
> 

You are describing the conventional rocket engine
which has poor efficiency.

New types of design, such as ion thrusters, can achieve
exhaust velocities of 20–50 km/s.

Currently ion thrusters have very low power, but it may
be possible to scale up the design to provide sufficient
acceleration.

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#640618

Dne 15/07/2017 v 14:55 F. Russell napsal(a):
> On Sat, 15 Jul 2017 13:34:56 +0200, Poutnik wrote:
> 
>>
>> and the state of art nozzle speed 4.5 km/s
>> for bi-component liquid fuel.....
>>
> 
> You are describing the conventional rocket engine
> which has poor efficiency.
> 
> New types of design, such as ion thrusters, can achieve
> exhaust velocities of 20–50 km/s.
> 
> Currently ion thrusters have very low power, but it may
> be possible to scale up the design to provide sufficient
> acceleration.
> 
I am aware of more advanced technologies,
that have not yet reached practical usability.

I have described what is available.

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640620

Dne 15/07/2017 v 14:55 F. Russell napsal(a):
> On Sat, 15 Jul 2017 13:34:56 +0200, Poutnik wrote:
> 
>>
>> and the state of art nozzle speed 4.5 km/s
>> for bi-component liquid fuel.....
>>
> 
> You are describing the conventional rocket engine
> which has poor efficiency.
> 
> New types of design, such as ion thrusters, can achieve
> exhaust velocities of 20–50 km/s.

About the efficiency, it is a half true.

The high expelling speed engines like ion ones
have better mass efficiency,
but worse energy efficiency.

10 times higher ion speed means
10 times higher energy per impulse ratio.

The most energy efficient reactive propulsion
uses big masses at low expelling speed,
like turbofan jet engines.

High expelling speed rocket jet engines
are not used for better energy efficiency,
but for better mass efficiency.


-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#640406

On Thursday, July 13, 2017 at 5:12:29 PM UTC-4, F. Russell wrote:
> On Thu, 13 Jul 2017 13:32:16 -0700, Mahipal wrote:
> 
> > No. There are GEO, LEO, ..., and polar orbits for spacecraft. Remember
> > the Irridium project of providing communications all the Earth over?
> 
> I'm not referring to earth orbiting spacecraft.  I am interested in
> interplanetary spacecraft that travel well beyond the vicinity of
> the earth.

So? Did my writing read like I was confused what you want to learn about?

Well, it's possible to expand/size polar/vertical orbits beyond just Earth.
I think I've pointed out how irrelevant that question is. Hey, I taught.

I'm a major Star Trek fan, mostly of just the original one. KirkJi. I'm watching
it one day, pondering why does the Enterprise never travel/fly in the 3rd
dimension? Next week or so, the show did a 3D CGI maneuver! I was like, Wow!
I can't precisely remember which episode/movie it was, maybe one with Piccard?

> AFAIK, there are no such spacecraft in orbits perpendicular to the
> ecliptic plane.  Even the Pioneer and Voyager missions, both of which
> are now far beyond the orbit of Pluto, are approximately within the
> ecliptic plane.

AFAUK? That's fine, no individual will ever know everything. But one can dream.

That's likely due to the lack of practical/engineering/need utility of such
perpendicular orbits. What's to be gained to going to where we already well
know that there's only nothing there? Pretty pictures? SW CGI can do that.

An ecliptic plane has a volume of zero. It has zero depth. Infinite area. 
An equatorial plane has a volume of zero. It has zero depth. Lots of area. 

Either do the homework of reading the book I referenced, else make your point.

If you believe rocket science is explicable by a/one/any trivial Usenet thread 
post, then... do you want buy a bridge from Bugs Bunny? I do need to monetize!
 
-- Mahipal “IPMM... माहिपाल ७६३८: d(me) != 0 ... me alwa(y)s changes... Enjo(y)!”   
Enjo(y)... Salute… Cheers... Open your M I N D… Time it is Is IS 3PM somePlace. 

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