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Unmanned Spaceflight.com _ Exploration Strategy _ GAO: The DSN is actually falling apart

Posted by: BruceMoomaw May 24 2006, 11:55 PM

http://www.gao.gov/docsearch/abstract.php?rptno=GAO-06-445

Posted by: Analyst May 26 2006, 09:14 AM

No Reply yet, although without the DSN no planetary exploration (unmanned or manned) can happen. The DSN is part of the invisible infrastructure we simply need before we start thinking about actual missions (like (E)ELVs, launch sites etc). It's very sad this essential networt is not in an optimal shape. A lot of missions with high data rates will stress the DSN and there is still only talk (and no money) about arraying a lot of small antennas (9m to 12m each) or optical communication. The DSN is the bottleneck. Part of the problem is no single mission pays for it, it's fixed costs nobody wants to pay but everybody uses the services. The situation also reminds me of the Apollo age infrastructure at KSC (VAB, pads etc.): 40 years and still useable, but how long?

Analyst

Posted by: Richard Trigaux May 26 2006, 10:44 AM

Things will not spontaneously become better.

DSN is based on a set of large antenna all around the world, so that a given source (for instance the MERs on Mars) can be received 24/24 hours.

In more of the quoted problem, a critical failure can occur, like the loss of one of the antenna (crashing down, like it aleady happened to a large dish, or a political setback in a country). I am afraid that for some timezones there is no redundancy, and the loss of only one antenna would create a blind zone, unability to receive certain sources at certain hours.

Anyway the only way to increase both safety and capacity of such a network is to increase the number of antennas all around the world. (whatever it is with few large antennas or many small ones)


With my opinion, such a unvaluable resource should become international and be managed by the UN. But the US government is known not to agree with such options, see with the ICANN. So international funding should come into the network, into the form of new antennas in new places, the whole thing managed like an economical association, and technically by a centralized unifom authority.

Posted by: Jim from NSF.com May 26 2006, 11:44 AM

QUOTE (Richard Trigaux @ May 26 2006, 06:44 AM) *
Things will not spontaneously become better.

DSN is based on a set of large antenna all around the world, so that a given source (for instance the MERs on Mars) can be received 24/24 hours.

In more of the quoted problem, a critical failure can occur, like the loss of one of the antenna (crashing down, like it aleady happened to a large dish, or a political setback in a country). I am afraid that for some timezones there is no redundancy, and the loss of only one antenna would create a blind zone, unability to receive certain sources at certain hours.

Anyway the only way to increase both safety and capacity of such a network is to increase the number of antennas all around the world. (whatever it is with few large antennas or many small ones)
With my opinion, such a unvaluable resource should become international and be managed by the UN. But the US government is known not to agree with such options, see with the ICANN. So international funding should come into the network, into the form of new antennas in new places, the whole thing managed like an economical association, and technically by a centralized unifom authority.




Why does it have to be a terrestrial system, an orbital system could work without the international implications.

Posted by: Analyst May 26 2006, 12:21 PM

(Upfront and/or operating) costs? Size (70m) and pointing problems? As for international problems: Australia and Spain are quite stable, aren't they?

Analyst

Posted by: Richard Trigaux May 26 2006, 02:28 PM

QUOTE (Jim from NSF.com @ May 26 2006, 11:44 AM) *
Why does it have to be a terrestrial system, an orbital system could work without the international implications.


Untill now, any spaceship ot satellite belongs to a country (except a bit for the ISS). So the legal problems are still the same, unless the things belong to a really international institution, like the UN.


Antennas in space have multiple advantages, they cannot be closed by a political setback, they can be pointed to a given source more time a day, etc. But make a 70m antenna in space is not among what is immediatelly feasible. And to maintain them seriously would require a space shuttle.

Posted by: Richard Trigaux May 26 2006, 02:45 PM

QUOTE (Analyst @ May 26 2006, 12:21 PM) *
As for international problems: Australia and Spain are quite stable, aren't they?

Analyst


Yes they are, but if an international problem occurs, as far as we know it will be unpredictable, unforeseen. So, when thinking of redundancy and reliability, we cannot say a priori that some countries are stable and others not. It is only a matter of probability. There is little political interest to duplicate an antenna in Spain, but anyway if the network is saturated, this antenna will have to be duplicated and it will be safer to do this in another country.

Think that Europe is in the process of duplicating the GPS system (with Galileo) at high cost, for the only reason that it is controlled by the USA, however a long friend, ally and helper country. This is not a criticism of the USA, but a wise caution.

Posted by: djellison May 26 2006, 03:28 PM

QUOTE (Jim from NSF.com @ May 26 2006, 12:44 PM) *
an orbital system could work without the international implications.


Would cost an extraordinary ammount of money, would still require a groundstation, and would be impossible to improve over time.

Doug

Posted by: RNeuhaus May 26 2006, 04:03 PM

What would be the solution? More 70 meters antennas or the same ones but bigger antennas, 140 meters? or employing a new antenna technology (no circular pads but somewhat a grid of lines). I am taking without thinking the money restrictions but only the next most recommeded antenna type for the new coming explorations which means more traffics, more wide-band requirements.

Rodolfo

Posted by: Richard Trigaux May 26 2006, 05:46 PM

A suggest RNeuhaus, there exist new antenna technologies which could do the same job than a large dish at a lesser cost. But it is physically impossible to reduce the size of the antennas, as this size is necessary to:
-gather signal power
-obtain a directionnal effect. (Both characteristics go together).


-dipole arrays. As indicated, they are simple receivers (dipoles or other microwave devices) mounted in an array. Each dipole has a phase shifter commanded by a computer in such a way that when we combine all their outputs, we receive the signal from only a specified direction. Such arrays are used for military radars in aircraft noses, saving the wheight of the orientation mechanism. At a pinch, the dipoles can be set on a non-planar surface, provided that the computer knows their position. The cost of such an antenna will rise as the square of their diametre, as each dipole has its own electronics. I don't know if they are cheaper than conventionnal dishes, probably not as there are no attemps to build any. Anyway it is simple to built phase shifters for a fraction of the wavelength, but a large dish would require electronic phase shifters for many times the wavelength, so I don't know if this is possible.


Flat striplines antennas use printed-circuits to build dipoles (or slots) and achieve their coupling. They still need to be oriented and rigidified like a dish, so like this we don't gain much. But, combined with the previous technology, we could use only one phase shifter per rank of dipoles. Such phase shifters, much less numerous, could be mechanical, and thus cheaper and with as much shift as desired. Such an antenna could simply lie flat on the ground (or better on water), needing only to be oriented into azimuth, the phase shifters doing the job of tuning the site. This is, as far as I know, the only way to save the building of a large mechanical structure, which makes all the cost of a large dish.



New materials with designed electromagnetic properties. This is very new in antenna technologies: materials which are regular arrays of filled conductors and gaps. Their geometries can be designed for, as an example, set a given propagation speed th electromagnetic waves travelling into them. So we could design lenses made of such materials. For a space application, the lens could be made of wires, rolled into a deflated baloon. Once into space, the baloon is inflated, putting all the wires in place. Then all the thing is rigidified, for instance with some polymer which hardens with UV. The ballon soon loses its gas, but no matter. The receiver is a but further, at the focal point of the lens. The advantage of this is that it don't require a large sized construction into space, a thing we don't know to do.


All those previous methods have the obvious drawback that they have a limited bandwidth. Only a true parabole could have a large bandwidth.

inflated parabolic dish . This idea is not new, and it is appealing: just with inflating a baloon in space makes a dish. But obstacles are many:
-inaccurate building
-the baloon soon loses its gas.
To overcome this I would suggest some use of electrostatic forces, repelling the two sides of the baloon, and keeping it "inflated" without gas. On the reflecting side, there would be many electrodes, each commanded independently, like into the adaptative optic mirrors. So they could maintain a correct shape, accurate enough, and focalise waves on the other side of the baloon where the receivers would stand. Into space this would work neatly.

Posted by: djellison May 26 2006, 06:22 PM

Were there any problems w.r.t. politicis, one could simply use a large ex-oil-facility such as they use for Sea Launch - pointing might be a bit of a problem in heavy seas - but it would be a hell of a lot cheaper and easier than an orbital facility.

But of course we're missing the point. We don't need any of this and the huge budget it would require..what we need is a more moderate investment in the current DSN.


Doug

Posted by: elakdawalla May 26 2006, 06:46 PM

There was a lengthy http://planetary.org/blog/article/00000570/ on what the DSN wants and needs to do to improve over the coming decades, and it basically involves replacing all the gigantic, one-of-a-kind antennas with arrays of 6-, 12-, or 18-meter dishes (they are still experimenting to figure out which one will be the optimal size). Unlike the big dishes, each of which needs its own operator, whole arrays can be operated by a single person; also they can plan to have some percentage of all the dishes down at any given time for routine maintenance. Also they can just devote as many dishes as they need to a single spacecraft, splitting the array to support several spacecraft at once or using the whole array for high bandwidth. They've got to be replaced because the big dishes cannot be upgraded to support Ka-band communications.

--Emily

Posted by: Jim from NSF.com May 26 2006, 07:01 PM

QUOTE (djellison @ May 26 2006, 11:28 AM) *
Would cost an extraordinary ammount of money, would still require a groundstation, and would be impossible to improve over time.

Doug


It would be the same as the TDRSS, but with larger antennas and facing outward. Only one US ground station would be required (spacecraft can crosslink). No atmospheric distortion. maintenance is easy, back up satellites. Upgrades would be easier, would be done like the GOES program, cut in upgrades in each series. O&M costs (after the initial investment) are lower since there is less manpower involved.

Antennas could be larger than any ground based.

Initial costs would be large, but lower in the long run.

Posted by: Richard Trigaux May 26 2006, 07:12 PM

QUOTE (elakdawalla @ May 26 2006, 06:46 PM) *
They've got to be replaced because the big dishes cannot be upgraded to support Ka-band communications.

--Emily


Yes if the price of a large dish is proportional to more than the square of the diametre, it is better to use a collection of smaller dishes, which cost is only proportional to the square of the (simulated) diametre.


Upgrading the larger dishes to higher frequencies would require to resurface them with a greater accuracy, a thing impossible as the dish somewhat flexes with its movement or with wind, it would need to be rigidified, that means completely rebuilt. So the price of a large dish sharply increases with frequency, while not with small dishes.

Maybe the solution would come from many small dishes spread by clusters or isolated all over the world, in more or less politically stable places, by any state which would want to contribute, or even by private owners. To cut the cost, we would use mass production for the dishes, and ship them by sea.

Posted by: RNeuhaus May 26 2006, 07:29 PM

QUOTE (elakdawalla @ May 26 2006, 01:46 PM) *
There was a lengthy http://planetary.org/blog/article/00000570/
--Emily

Very informative is the Planetary Society's blog about DSN. This has satisfied me almost all my inquiries. smile.gif

Rodolfo


QUOTE (Richard Trigaux @ May 26 2006, 12:46 PM) *
A suggest RNeuhaus, there exist new antenna technologies which could do the same job than a large dish at a lesser cost. But it is physically impossible to reduce the size of the antennas, as this size is necessary to:
-gather signal power
-obtain a directionnal effect. (Both characteristics go together).
...

Thanks much for the detailed antenna technologies. I think that the array of antenna along with optical antennas are the best candidates to attend the future increased bandwidth and transmission traffic.

Rodolfo

Posted by: Chmee May 26 2006, 07:42 PM

QUOTE (Richard Trigaux @ May 26 2006, 06:44 AM) *
With my opinion, such a unvaluable resource should become international and be managed by the UN. But the US government is known not to agree with such options, see with the ICANN. So international funding should come into the network, into the form of new antennas in new places, the whole thing managed like an economical association, and technically by a centralized unifom authority.



Why should the UN manage a resource that was designed, built, enginneered, and most importantly, paid by the US? Should Germany turn over the Autobahn or the UK the North Sea oil platforms to the UN because they are invaluable? This network was not cheap and being so valuable it should remain under control of the country that had the will and means to build it.

Posted by: djellison May 26 2006, 07:44 PM

There is already international involvement to some extent, with ESA building smaller facilities of it's own in various places.

There is no way in hell the UN should ever have control over the DSN. The US built it, the US use it, the US pay for it.

Doug

Posted by: AlexBlackwell May 26 2006, 07:48 PM

QUOTE (djellison @ May 26 2006, 07:44 PM) *
There is no way in hell the UN should ever have control over the DSN. The US built it, the US use[s] it, the US pay[s] for it.

Doug, if you keep talking like that, we're going to have to make you an honorary U.S. citizen à la Churchill biggrin.gif

Posted by: djellison May 26 2006, 08:14 PM

Truth be told, I could go even further and say that the generosity with which DSN facilities have been made available to ESA could justify in some way a contribution from those nations...of course it's very give and take with things like this - you scratch our back..we'll scratch yours etc.

One thing that I've thought of...there was a detailed breakdown of estimated DSN costs for missions in the recent as a function of number of contacts per week, length of contacts, and facility size required etc in available in the library of the current Discovery AO
http://discovery.larc.nasa.gov/PDF_FILES/NASA_MO_MS-Update061.pdf

I'm not sure how the funding for a facility like this works - but I presume it's income is both from funding on a mission by mission basis as outlined in that doc, and also general DSN funding from NASA that's for maintainance and upgrades as opposed to normal running costs.

Perhaps one or the other needs a bit of a hike.

Doug

Posted by: Richard Trigaux May 26 2006, 08:23 PM

QUOTE (djellison @ May 26 2006, 07:44 PM) *
There is already international involvement to some extent, with ESA building smaller facilities of it's own in various places.

There is no way in hell the UN should ever have control over the DSN. The US built it, the US use it, the US pay for it.

Doug


In hell, I don't know, I never visited this place, and I don't intend to go, if even it exists.

But I know what is possible or not on Earth. There are technical limitations, and often far before we meet them, there are political/psychological limitations.

So what is the most likely to happen is that Europe, or others, will sooner or later build their own DSN stations, like with Galileo and GPS. Of course, of the point of view of bandwith and availability, these several DSNs will be the exact equivalent of having one internationaly operated DSN, sharing its resources among countries. Child-minded politicians will be proud of THEIR network, and scientist will have means to work seriously. We shall just have to pay several times the development costs.

Chmee, autobahns in Germany can remain german, unless you find a mean to transport them in other places.

Posted by: AlexBlackwell May 26 2006, 08:28 PM

QUOTE (Richard Trigaux @ May 26 2006, 08:23 PM) *
So what is the most likely to happen is that Europe, or others, will sooner or later build their own DSN stations, like with Galileo and GPS.

I wouldn't be surprised if that indeed comes to pass, Richard. I also wouldn't be surprised if at some point after that happened that "Europe, or others" would, say, issue ESA-like press releases claiming they built the first deep space network.

Posted by: Richard Trigaux May 26 2006, 08:36 PM

QUOTE (djellison @ May 26 2006, 08:14 PM) *
Truth be told, I could go even further and say that the generosity with which DSN facilities have been made available to ESA could justify in some way a contribution from those nations...of course it's very give and take with things like this - you scratch our back..we'll scratch yours etc.

...

Doug


Added later (previous reply by Doug added during editing my own)

Of course, Doug, whatever the ownership and leadership of the DSN, users will have to contribute in a way or another. There is no reason (save pure generosity) that the US pay for others. This contribution can take the form of a rent, or new facilities added. But if other countries contribute with new facilities, they will sooner or later claim some leadership. And there are only two solutions:
-an international organism managed by contributor countries
-a UN organism.
That makes little difference though, except that some politicians in the US don't like the UN.

QUOTE (AlexBlackwell @ May 26 2006, 08:28 PM) *
I also wouldn't be surprised if at some point after that happened that "Europe, or others" would, say, issue ESA-like press releases claiming they built the first deep space network.


I don't know to what you allude to, but I agree it would not be honest. US clearly has at least forty years in advance. Only the Russians could say they have some kind of DSN, but it was made only of ships able to receive only communications from low orbit, and some large antennas on their territory, not a network all around the world able to receive signals from mars or beyond.



This discution is becoming quick and interesting, but I don't have a DSN for me and here in France it is time to shut down my station. Bye, to the next communication window.

Posted by: Bob Shaw May 26 2006, 10:48 PM

QUOTE (AlexBlackwell @ May 26 2006, 08:48 PM) *
Doug, if you keep talking like that, we're going to have to make you an honorary U.S. citizen à la Churchill biggrin.gif


Alex:

Surely his Ma was American, anyway? That's WLSC, not DE!

Bob Shaw

Posted by: Bob Shaw May 26 2006, 11:01 PM

QUOTE (Richard Trigaux @ May 26 2006, 08:12 PM) *
Maybe the solution would come from many small dishes spread by clusters or isolated all over the world, in more or less politically stable places, by any state which would want to contribute, or even by private owners. To cut the cost, we would use mass production for the dishes, and ship them by sea.


Richard:

I'm for the democratisation of data, so far as possible, and the notion of many dish arrays is very attractive.

We need to look not only to the current costs of spacecraft data reception, but also the 'distant' costs - Voyager being a prime example. Imagine if Alexander Carnegie funded the Voyager Interstellar Mission, and the new institutions which would be required (anybody want to mention SETI?). We see another analogue in AMSAT, or even SLOOH. The bottom line is that a paradigm shift has to come, whether it be commercial or non-commercial - the rate of change in the volume of data transmission across the Solar System may not follow Moore's Law exactly, but it's certainly in the same league!

Bob Shaw

Posted by: DonPMitchell May 27 2006, 02:21 AM

QUOTE (Richard Trigaux @ May 26 2006, 01:36 PM) *
Only the Russians could say they have some kind of DSN, but it was made only of ships able to receive only communications from low orbit, and some large antennas on their territory, not a network all around the world able to receive signals from mars or beyond.


Russia has had a serious DSN since 1960, with a higher interplanetary bandwidth than the US, before the construction of the 64-meter Mars antenna at Goldstone. The Western center was in the Crimea, and the Eastern center was in Ussuriysk, and a couple big radio telescopes that also seconded at telemetry receivers near Moscow.

The Pluton system was the first component, built in 1960 near Yevpatoria. It consisted of three antennas, each of which was an array of 8 dishes on a common mount. It transmitted and received PCM coded data on decimeter and centimeter bands, and it could receive orthogonal coded (PPM) signals on a centimeter band. They also built a 32-meter dish just prior to that in Simferopol', to be used for lunar missions.

[attachment=5886:attachment] [attachment=5890:attachment]
(Pluton receiver site and transmitter site)

In the mid 1960s, a new system was constructed called Saturn, designed for the manned Moon program, but also purposed for interplanetary communication. It consisted of a great number of 25- and 32-meter antennas at a number of sites throughout the Soviet Union. The two 25-meter antennas seen in the upper right above are part of that system. Pluton was also upgraded, and began to use biorthogonal coding. They could send telemetry reliably at 400 bits/sec by then, and images at up to 6144 bits/sec.

[attachment=5891:attachment] [attachment=5892:attachment]
(70-meter installation, 64-meter antenna at Bear Lake)

In the early 1970s, a 70-meter antenna was built in the Crimea, and a second built in the Eastern center in Siberia. At the time, they were the largest steerable parabolic antennas in the world (Goldstone later upgraded its 64-meter DSN to 70 meters, with extensions to the dishes). This system, called Kvant ("quantum"), was used for Venera-13 and later missions. It's still in use today, and has been upgraded to be essentially identical to the American system. The two Russian 70-meter dishes, and the three American ones have been used together a few times, like during the Vega mission.

Posted by: djellison May 27 2006, 07:05 AM

ESA is slowly getting there with a DSN of it's own...
http://www.esa.int/spacecraftops/Image/urlpicturelarge_id_1069167507833_ant_infra_section3_l.jpg

Also - just looking at the GAO report - they only visited Goldstone...no site visits for Spain or Aus which seems a bit of a half-arsed job to be honest.

Doug

Posted by: Richard Trigaux May 27 2006, 07:30 AM

Thanks DonPMitchell to bring more exact info than I did.

So we have larges dishes available in Russia for PRACTICAL use (and they were already used).

What interesses me is to have practically available facilities, to be used in missions.

A common technical control would be fine.

After, what politicians say, it is MY antenna, I don't care, so long as THEIR antenna is actually used to receive OUR data when this data is coming.

Of course we are still today with most of the US DSN used for US missions, and russian antennas used for russian missions, it is quite normal. There are still now few users. But things will change, and it will require sooner or later a better technical direction, together with a common economical/political management in a form or another.

By the way, ESA used the DSN, but MERs used the european Mars satellite as a relay. Accounting such feats in terms of political revenges or involving the Irak problem is definitively petty. Accounting in bucks may be unavoidable. Saying it is INTERNATIONAL COOPERATION would be clever.

Sorry Doug and some others, nobody was never able to explain me for what purpose boundaries were created. As far as I know, it is an old custom dating back to the chimpazees, who have a sharp notion of clan territory. But today we are clever and nice guies comitted to build a pleasant world for us all. This will not remove boundaries right now, but the way of evolution is toward more and more international cooperations, international bodies, international authorities, etc. Even the US who don't like the UN, created the WTO, world bank, and others. Especially about space, it will lead to more and more international cooperations and international projects, India using european rockets and the DSN, etc. Even the ISS problems will not reverse this tendency, I think, it will just make people more cautious.

Anyway going more international will be necessary, from down to earth reasons (bucks) to more philosophical reasons (sending a spaceship to stars, in the name of who?)

Back to DSN, a country like France still own Guyana and many islands in south Pacific and south Indian ocea, which are desert or politicaly stable. They could provide many places for antennas at longitudes where there are not many stable countries. Emerging countries like India or Brazil could be interested too.

Perhaps the furure legal ownership of the DSN will be some kind of formal shares society, where everyone will bring something (US first, of course) in exchange of a guarantee on availability.

Posted by: djellison May 27 2006, 07:39 AM

QUOTE (Richard Trigaux @ May 27 2006, 08:30 AM) *
But things will change, and it will require sooner or later a better technical direction, together with a common economical/political management in a form or another.
...
By the way, ESA used the DSN, but MERs used the european Mars satellite as a relay.



On the first point - I don't see any change. Those 'doing space' are developing the resources to talk their assets. The DSN needs more cash for maintainance and upgrading, but it doesnt require external management. To be honest, demanding an external body manages the DSN is a bit like a kid trying to steal someone elses sweets.

And MER used Mars Express as little more than a tech-demo to check compatability and functionality of the UHF payload on MEX - as a percentage of data returned, MEX would be considerably less than a percentage point.

Doug

Posted by: garybeau May 27 2006, 01:26 PM

Regardless of how much money is spent upgrading the current DSN, it will never meet the demands
required in the coming decades. I really think it's time to start forging ahead with an optical communication
infrastructure and maintain the current DSN for existing and short term future missions. Optical communications would allow a 10-100 times increase in data transmission. As mentioned above, it's not
practical to put a 70 meter dish in orbit, but it's very practical to put an optical receiver in space.
A synopsis of some of the work Nasa has been doing in optical research can be found here:

http://lasers.jpl.nasa.gov/PAGES/about.html

I'm sure ESA must have a similar program in the works also.

Posted by: DonPMitchell May 27 2006, 03:57 PM

Space programs have a long history of "Not Invented Here" syndrom, as well as being nationalistic. Witness the exercise of duplicating the GPS system in Europe, for example. I think with DSN, you can at least argue that scheduling issues make it advantageous for each program to have its own system.

With regard to politcial stability, what is the situation in the French Guiana? There has been an ongoing struggle for independance in New Caledonia for years now, with occasional outbursts of violence. That would be a setback for ESA if things got strange there, and Washington would definately not help (given their long lasting "Monroe Doctrine" sentiment).

Posted by: helvick May 27 2006, 05:04 PM

QUOTE (DonPMitchell @ May 27 2006, 04:57 PM) *
With regard to politcial stability, what is the situation in the French Guiana? There has been an ongoing struggle for independance in New Caledonia for years now, with occasional outbursts of violence. That would be a setback for ESA if things got strange there, and Washington would definately not help (given their long lasting "Monroe Doctrine" sentiment).

French Guyana has never really had much of an independance movement, there are some pushes towards increased autonomy perhaps but there isn't much evidence for a genuine militant independance movement. As an overseas département It is fairly well integrated into France politically and economically but it is a particularly impoverished spot, it is a remnant of colonialism and it is far away so there probably are some risks. I don't think they are significant at this point though.

New Caledonia on the other hand is an overseas territory in an unusual phase since it is in the process of devolving from France and while it is still part of the French Republic at the moment the current plan is to vote on an independance referendum in 2014. It has had a pretty violent independance movement in the recent past but the current process seems to be sort of keeping the lid on things for now.

Still the point is well made - political instability in French Guyana would be highly problematic for ESA. I wouldn't want to see it happen but it would be interesting to see how the French would deal with it - I suspect that Kourou is considered a strategic asset so I can't see the French just idly sitting by if things got unstable. I think you are right as far as the Monroe Doctrine is concerned but I also think that pigs would be seen flying over The Champs Elysees before the French would ask for US assistance in what it would consider an entirely internal affair.

The history of the DSN might have seen some similar problems - the removal of Haartebeeshoek in South Africa to be replaced with Madrid in the mid 70's probably had some political motivation behind it for example.

Posted by: DonPMitchell May 27 2006, 05:31 PM

I agree, Kourou is strategically important, it would certainly be defended. The EU has very limited ability to project military power (except for Britain), but it doesn't sound like this is an issue to worry about.

Launching from the equator is energy efficient, but that's not really the important issue. It's all about getting comsats into geosychronous orbit, without having to develop expensive and complex technology to change orbital plane. That's where the money is too. Kourou is all about skimming the cream off the commercial satellite business, with cheap simple technology. An elegant solution, but very special-purpose.

Changing the plane of an orbit is complex and energy-expensive, and at the moment Arianespace lacks the technology to do those kinds of maneuvers. The Soviet Block-L stage was the first step taken there, but it could only supply one impulse -- which is enough to give you interplanetary escape or to give you a very eccentric high orbit like Molniya, but not enough to circularize a high orbit or change the plane. You really need something like Centaur or Fregat or Briz stages, which I imagine are full of closely guarded engineering secrets.

The ESA must be working on this problem, for the European ISS supply ship. But getting from Kourou to the highly-inclined ISS orbit seems like a bad idea. Military and Earth-resource satellites, which ideally have near-polar orbits, must be almost impossible (thus the remaining tie to the Soyuz system).

Posted by: Richard Trigaux May 29 2006, 12:58 PM

QUOTE (DonPMitchell @ May 27 2006, 03:57 PM) *
With regard to politcial stability, what is the situation in the French Guiana? There has been an ongoing struggle for independance in New Caledonia for years now, with occasional outbursts of violence. That would be a setback for ESA if things got strange there, and Washington would definately not help (given their long lasting "Monroe Doctrine" sentiment).


French guyana has only some indian tribes as autochtonous population. They will not create problems and know they have no interest to do so, or that they have better remain french than otherwise. The growing problem however is a number of illegal brazilian immigrants (poor people seeking some land to cultivate, gold seekers, etc). It is a serious issue, but nobody fears it could come to an independency fight. The situation is very different of New Caledonia, where Kanaks are numerous with an accute sense of their property. Eventualy a left wind french government could grant them independency, if there was not many french people too. South Pacific islands are somewhat independence-prone too, but nobody believes it could come to a real fight. This makes still many places, especially in southern Indian ocean, where France has some large desert islands (like Kergelen) where the only problem is the harsh climate.

Posted by: Richard Trigaux May 29 2006, 01:14 PM

QUOTE (helvick @ May 27 2006, 05:04 PM) *
New Caledonia .... It has had a pretty violent independance movement in the recent past ...


Not exact, I think. The Kanaks, like many other people in the world, have a somewhat rituellic way to avoid the crude violence of an open conflict. What they did was to symbolicaly hijack some people in a sacred cave. These people were never in life threat, although nobody knows how long they could stay here. The problem which happened was that the police did not understood that, and they reacted as with dealing with true terrorists, invading the cave (an unthinkable thing for the Kanaks, who considered the place as sacred, just expecting to engage a discution) and killed the hijackers. Lucky if they did not provoked large reprisals in a palestinian style.
This said, however, I shall not be surprised if New Caledonia obtains its independency.




QUOTE (helvick @ May 27 2006, 05:04 PM) *
The history of the DSN might have seen some similar problems - the removal of Haartebeeshoek in South Africa to be replaced with Madrid in the mid 70's probably had some political motivation behind it for example.


Probably yes it had, and a good one: boycott of the apartheid. Now this problem is solved, and the situation stabilized, but years of peace will be still needed to create a real confidence here and at large in Africa.

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