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Next Goals For The ESA
zeux writes "With all the news we got recently from space I tried to gather some information about the next goals of the ESA (European Space Agency). Along with a space vehicle designed to carry supplies to the ISS between 2004 and 2013, they are working on the new 'Vega' launcher (2006) and still playing with the SMART-1 probe which is slowly heading to the moon testing an ion drive that is ten times more efficient than the usual chemical systems (1500 hours cumulated thrust time so far)."
What are the technical obstacles to Lagrange point colonies?
I've only read that Xenon is used in current Ion drives... kinda wondering why more common gasses *read, nitrogen, probably the cheapest* can't be used. Anyone know?
"Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
The Italians had to fight tooth and nail to get the Vega launch system to be accepted by ESA for development. Part of it was, again, iirc, because it was would be separate from Arianespace. The whole point was to have an European developed follow-on for the Scout rockets that the Italians were building under license from the US.
The ATV is an excellent idea. I find it a little sad at this point that ESA hasn't successfully gone down the path of an independant manned space flight capability. Sure, they can use the Russians or the US or even the Chinese, I suppose, but it'd be interesting to see ESA come up with their own. I know they tried the Hermes space plane, but that turned out to be something of a boondoggle, didn't it?
Do you know why the road less traveled by is littered with the bones of the unwary?
Nasa also has a probe headed to Saturn. Its called Cassini, and should be seven months, though its only an orbiter.
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http://saturn.jpl.nasa.gov/news/press-releases-
Oh my, I think Dave just turned into a bear.
The ATV design strikes me as particularly interesting because it brings up a point that I've been wondering for awhile: Why don't we have more automated exploration and maintenance vehicles in Earth orbit. It seems to me that a spacecraft that could launch, orbit earth, and return to earth (not that the ATV can do that) without humans onboard and built in a mass manufactured way would be extraordinarily effective for Earth orbit science experiments. It might also be useful for maintenance of high value satellites (like HST). Since Earth orbit is almost real-time transmission there is no reason to think that putting a mechanical arm on a spacecraft to do maintenance would be any different that a surgeon doing a remote operation via a mechanical hand. The most complicated part would be the approach of the satellite to be maintained, but since the Space Shuttle obviously had no problem doing this there is no reason to believe that an automated spacecraft (with real-time human backup in a controlling station) couldn't do the same (a little more complicated than the ATV's purpose of docking with the ISS, but I don't think its inanely so).
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
They should get together ...
The Huygens is being carried on the Cassini orbiter until it will be released in the same manner as the probe from the Galileo.
Still, it works, but it's not even as efficient as chemical rocketry
One word: fusion. As soon as fusion comes along, coupled with ion drives, chemical rocketry is history. Period.
Tubal-Cain smokes the white owl.
OTOH, a fairly fast trip to Mars requires about 20 kps in velocity changes. Which makes a 30 kps ion drive just about right.
But there's complexities there, too. Most of these velocity changes come at the beginning and end of the journey (getting into an elliptical orbit, then getting out of it once you reach Mars).
Perhaps they are not the most efficient for Mars travel, but much beyond that, give me a break (having not done the math for Mars, I don't know). Chemical rockets spit far too much of their inital mass out the back to be even *somewhat* considered for longer term missions (remember the rocket equation?). There are several differnt kinds of "ion" engines all of which exceed 50% efficiency. At this point it becomes a bit more important to define "efficiency" - (power in)/(power out) may not necessarly be relevent if (mass start)/(mass end is near zero [what is the point of accelerating all of your "80%" fuel if you fling the crap out the back in a somewhat effiecent matter?) I may be (ok I am) a bit baises since I'm a grad student working in Ion Propulsion but the field obviously has merit or I would not have funding.
Apart from the fact that you will have to modify the ATV pretty heavily to make it work... for starter, even I can see that you must:
- Provide a larger engine for orbital manuvers. The old Apollo system had a trust of 97860 N (roughtly ren (metric) tons), while the ATV has an enginetrust of a paltry 1960N (or about 1/50 of the Apollo).
- Provide some form of manrated capability. The ATV is launced unmanned, and as far as I can see from the article carries no life support system on it's own.
- Some form of reentry capability must be provided, unless you plan to dock at the ISS on the way home. If you do plan to dock at the ISS, you need to carry enought fuel to brake down and enter earth orbit.
I fear that modefying a ATV can turn out to cost more and provide a less optimum vessel for going to the moon than a new design based on the Apollo. Despite the fact that the design of the Apollo is close to 40 years, they got a lot of things right, and a few wrong. Possible (cheap) ways to optimise the Apollo design might include:
- Use of a Soyuz-shaped return vehicle (better volume-weight ratio than the coneshaped Apollo).
- Modern electrics (lighter, less bulky, uses less power).
- Solar panels instead of fuelcells (solar panels have come a long way since the early sixties, and you don't have to carry along oxygen and hydrogen to make them work).
- An ion engine for long duration, low trust burns to optimise trajectory (?).
I am not a rocketscientist, but I don't see how the ATV cam be a good choice to go to the moon. It's designed to be a cargotruck, not a manned vessel for going far into space.
Everything in the world is controlled by a small, evil group to which, unfortunately, no one you know belongs.
It's interesting that one of ESA's greatest achievement areas, namely Earth Observation (things like ERS 1/2, Envisat) are not mentioned. This is an important area, with all the exciting stuff about oceans rising and engulfing towns and the Seychelles (serves them right for living in a bloody paradise :D). There are a large number of unknowns regarding the Earth's environment that could be alleviated by a (relatively) cheap fleet of EO microsatellites. I don't know whether ESA wants do commit more budget to these areas (after all, a lot of the stuff on Envisat is only of very limited commercial interest, and they seem to be pushing for commercial use), but it certainly would help. On the other hand, looking at the deforestation rate over Siberia might not be as cool as putting some gimp on the Moon...
As has been done in the past with Soviet missions, both Mars and Venus will get probes, using some spares and the design from the first launch for the second probe.
In this case, the second probe will be launched as Venus Express. This will be launched in Nov 2005, also by Soyuz from Baikonur Cosmodrome in Kazachstan.
Soyuz is working out so well, that ESA is building Soyuz launch facilities in French Guiana - which is of course MUCH nearer the equator and is E.U. territory. (It's a problem for Russia that Baikonur is no longer in their territory).
Then there's Rosetta, this flagship mission will be launched in a month or so. It's a mission to chase a comet, taking TEN years to catch it! It will also flyby at least one asteroid.
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