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Comment: So much armchair engineering (Score 1) 523

by j-b0y (#48425169) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

It was looked at and rejected in favour of high efficiency solar cells. At the time of the design of Philae (early-mod 90s?) there were no European designs for an RTG nor any expertise in building them. If the Philae consortium wanted an RTG they would:

- Source it through the US -- you couldn't exact buy them off the shelf and have all the attendant ITAR baggage that would go with it. Since it would practically work as a US contribution to Philae there would be some science exchange in return. Not impossible, but at that time was there any US money to fund a further contribution to Rosetta from the US on what was quite a high-risk project? Not clear... It also goes right against one of the core principles of ESA which is to invest in/support European technology development.

- ... or fund the development of a European RTG; high risk and probably prohibitively costly for the money available to support the mission and meet the mass budget available for Philae. No doubt that mature designs probably do not have a huge mass penalty, but a new design? Who knows, or would want to take the risk?

- There was at the time quite considerable political resistance in certain European countries to RTGs in space. IIRC Germany was one of them and this would have put a big obstacle in the way. Development of solar panel technology was and still is considered an important goal and improved solar cell technology would be an important spin off.

In the end it really does come down to politics; the safety issues could have been mitigated (at some cost), but there was no political will to go in the direction of RTGs. It will be interesting what will be selected for JUICE...

Incidentally Rosetta itself suffers to a certain extent from choosing solar panels - the long array is turning Rosetta into a windmill that is quite difficult to steer. RTGS would have allowed a smaller array.

Comment: Re:Except it is not actually in space (Score 1) 21

by j-b0y (#46901345) Attached to: ESA Taking Applications for Summer of Code in Space

Since ESA depends on it's member states for it's funding and the funding is given on the basis of the political objectives of the states, ESA it by it's nature a political one and always has been. But that does not exclude being a technical one as well, which is it, and quite deeply.

The "rich old white men" are in fact the european space industry, which ESA supports and promotes as one of it's primary functions.

Your ignorance appears boundless.

Comment: Re:Total map size (Score 2) 77

by j-b0y (#45744965) Attached to: Billion Star Surveyor 'Gaia' Lifts Off

Very little that Gaia observes is truly discarded -- just the main astrometric system needs a mix of stable, well behaved stars and very distant quasars, that could be between 10% and 50% of the objects detected. There will be an attempt to classify objects -- which you need to do in order to grab the quasars for the astrometric system

Comment: Re:The real test... (Score 1) 77

by j-b0y (#45744945) Attached to: Billion Star Surveyor 'Gaia' Lifts Off

Well, Gaia won't ever observe the Moon, nor Venus and Mercury which are always on the sun-ward side of the solar-shield. Jupiter is so bright that it really messes with the detectors when it transits the focal plane, but it should be possible to do some interesting general-relativity experiments with the light-bending effects of Jupiter's mass for stars that are close (not not too close) to Jupiter when Gaia observes near it.

Comment: Education (Score 1) 397

I think a necessary step is to make sure that there is a general understanding that this is a problem -- here we must not merely preach to the choir but reach a wider and maybe technically illiterate audience) Who are we dealing with

1. People who willingly forgo their right to privacy (and therefore understand the issue at hand)
2. People who are ignorant their privacy rights are not respected (and therefore do not understand the issue at hand)
3. People who are aware that their privacy rights are not respected but wish to interact with 1) and 2) and therefore give up some or all of their privacy rights (and therefore understand the issue at hand)
4. People who will protect their privacy rights at the cost of limiting their ability to interact with at least those in 1) and 2) (and therefore understand the issue at hand)

We cannot save those in category 1), they know the risks and accept the "terms and conditions" of using the internet with public and private data mining/surveillance in place. These people are lost to the Dark Side.

People in category 2) need education on what the consequences of their actions are, and may then resolve into one of the other groups.

People in category 3) should accept that their permissiveness strengthens the hand of the NSA et al. If a practical alternative solution is presented they will probably help to bring people in category 2 away from the Dark Side.

People in category 4) are probably a small population already using Tor, Freenet, PGP, etc. They can help by adopting new technologies that do not compromise (too much) their desire for privacy.

Comment: It's all about the payload (Score 1) 188

by j-b0y (#42026597) Attached to: Ariane 5 Has No Chance, Says Elon Musk

Ariane 5 is and continues to be a success but the premise on which Ariane 5 was built -- heavy payloads -- is a small and shrinking market segment. Ariane 5 can launch two payloads, but matching payloads -- the right orbital configuration and mass constraints -- is not easy.

Arianespace hedged their bets by bringing this Soyuz launchers over to CSG with a new (ESA-funded) launchpad at Sinnamari. The much smaller Vega rocket is way off in the distance. The reasoning for Ariane 6 (not having to pay the Russians, as far as I can work out) is sound enough, but the politics (money for France for A6 vs money for Germany for revised A5) is getting in the way.

Do you suffer painful illumination? -- Isaac Newton, "Optics"

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