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In terms of country based quotations ("Most scited countries") I cannot access space science, only Geosciences, Immunology, Material Science, and Psychiatry & Psychology. But when I first saw the list of countries at the left under "Impact in Science" I saw Argentinia was on top, and USA was on last position. Yes, I was surprised, until I realised that is was just an alphabetical order. Did you see the same list?

scotland's a separate country. must be preparing for independence already. and it's highest percentage is for space science. crazy

Dajan, you need to click on the country you are interested in ....

Nooo, can't be THAT simple.

data a bit old .... newer data (but less well presented) at http://sciencewatch.com/ there you can also read: "The 20th century was largely dominated by the US as a major powerhouse of scientific research and innovation, with 40% of the papers indexed in the Web of Science fielded by US scientists in the 1990s. By 2009, that figure was down to 29%. The US now struggles to keep pace with increased output from Europe and Asia."

hottest space science paper in January 2012: Field: Space Science Article Title: Herschel Space Observatory An ESA facility for far-infrared and submillimetre astronomy Authors: Pilbratt, GL;Riedinger, JR;Passvogel, T;Crone, G;Doyle, D;Gageur, U;Heras, AM;Jewell, C;Metcalfe, L;Ott, S;Schmidt, M Journal: ASTRON ASTROPHYS, 518: art. no.-L1 JUL-AUG 2010 * ESTEC SRE SA, ESA Res & Sci Support Dept, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands. * ESTEC SRE SA, ESA Res & Sci Support Dept, NL-2201 AZ Noordwijk, Netherlands. * ESTEC SRE OA, ESA Sci Operat Dept, NL-2201 AZ Noordwijk, Netherlands. * ESTEC SRE P, ESA Sci Operat Dept, NL-2201 AZ Noordwijk, Netherlands. * ESOC OPS OAH, ESA Mission Operat Dept, D-64293 Darmstadt, Germany. * ESAC SRE OA, ESA Sci Operat Dept, Madrid 28691, Spain.

Interestingly, Space Science is the only field in which my country has positive "Impact vs. world" value (even more interestingly as we don't even have a proper national space agency)...

Riemann hypothesis should be next... Which paper on the linked website is this exactly?

hmmm, last year at the AIAA conference in Toronto I presented a continuation approach to design a DRO (three-body problem). Nothing new here unfortunately. I know the work of Caillau, although interesting what is presented was solved 10 years ago by others. The interest of his work is not in the applications (CR3BP), but in the research of particular regularity conditions that unfortunately make the problem limited practically. Look also at the work of Mingotti, Russel, Topputo and other for the (C)RTBP. Smart-One inspired a bunch of researchers :)

Topputo and some of the others 'inspired' researchers you mention are actually here at the conference and they are all quite depressed :) Caillau really solves the problem: as a one single phase transfer, no tricks, no misconvergence, in general and using none of the usual cheats. What was produced so far by other were only local solutions valid for the particular case considered. In any case I will give him your paper, so that he knows he is working on already solved stuff :)

Answer to Marek: the paper you may look at is: Discrete and differential homotopy in circular restricted three-body control

Ah! with one single phase and a first order method then it is amazing (but it is still just the very particular CRTBP case). The trick is however the homotopy map he selected! Why this one? Any conjugate point? Did I misunderstood the title ? I solved in one phase with second order methods for the less restrictive problem RTBP or simply 3-body... but as a strict answer to your title the problem has been solved before. Nota: In "Russell, R. P., "Primer Vector Theory Applied to Global Low-Thrust Trade Studies," JGCD, Vol. 30, No. 2", he does solve the RTBP with a first order method in one phase.

I think what is interesting is not what he solved, but how he solved the problem. But, are means more important than end ... I dunno

I also loved his method, and it looked to me that is far more general than the CRTBP. As for the title of this post, OK maybe it is an exageration as it suggests that no solution was ever given before, on the other end, as Marek would say "come on guys!!!!!"

The generality has to be checked. Don't you think his choice of mapping is too specific? he doesn't really demonstrate it works better than other. In addition, the minimum time choice make the problem very regular (i guess you've experienced that solving min time is much easier than mass max, optimality-wise). There is still a long way before maximum mass+RTBP, Topputo et al should be re-assured :p Did you give him my paper, he may find it interesting since I mention the homotopy on mu but for max mass:)

Joris, that is the point I was excited abut, at the conference HE DID present solutions to the maximum mass problem!! One phase, from LEO to an orbit around the moon .. amazing :) You will find his presentation on line.... (according to the organizers) I gave him the reference to you paper anyway, but no pdf though as you did not upload it on our web pages and I could not find it in the web. So I gave him some bibliography I had with be from the russians, and from Russell, Petropoulos and Howell, As far as I know these are the only ones that can hope to compete with this guy!!

for info only, my phd, in one phase: http://pdf.aiaa.org/preview/CDReadyMAST08_1856/PV2008_7363.pdf I prefered Mars than the dead rock Moon though!

If you send me the pdf I can give it to the guy .. the link you gave contains only the first page ... (I have no access till monday to the AIAA thingy)

this is why I like this Diigo thingy so much more than delicious ...

What do you mean by this comment, Leopold? ;-) Jokes apart: I am following the Diigo thingy with Google Reader (rss). Obviously, I am getting the new postings. But if someone later on adds a comment to a post, then I can miss it, because the rss doesn't get updated. Not that it's a big problem, but do you guys have a better solution for this? How are you following these comments? (I know that if you have commented an entry, then you get the later updates in email.) (For example, in google reader I can see only the first 5 comments in this entry.)

mmm, I think that if we manage to travel at 99.999998 per cent the speed of light, we'll have the technology to deviate these atoms ! one way could be a super strong magnetic field, or a super laser that would act as an ice breaker with the radiation pressure (the good thing is that light always travel at the speed of light, even if you are at 99.999998 per cent the speed of light)