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The usefulness of having a robust trajectory :) ... They have to wait 6 more years for another date with Venus ...

"optimised trajectory" of course not, robust definitely! It was the subject of my paper presented at the AAS (the one in San Diego) "Designing robust interplanetary trajectories subject to one temporary engine failure". The problem here is that they do not have enough fuel for a correction maneuver that would allow to come back to Venus earlier, and break for a VOI. A robust scenario could have alloted the best amount of fuel and time to be able to recover from almost all possible unplanned events. In the paper, I introduce some confidence regions such that I get the robust control for p% chance of mission success in case m% chance of problem with the propulsion system.

You should run your method on this scenario and see if you could get a trajectory with a shorter come back time using the same spacecraft.... would be a big selling point for a new trajectory design approach

"Scientists are planning to use NASA's Hubble Space Telescope to observe next month's historic transit of Venus across the sun's face. But there's a twist. Researchers can't point Hubble anywhere near the sun, because our star's bright light could damage the telescope's super-sensitive instruments. So Hubble will watch the June 5-6 Venus transit by using the moon as a mirror."

aha. i suggested something like this a few years ago

Just in case you missed these one... should be of interest for ACT's climate modelling squad. "As well as telling us more about Venus, it could be sending a warning to those on Earth seeking to inject our atmosphere with sulphur droplets in an attempt to mitigate climate change."

Our friends from NASA have come out with a plan to the human exploration of Venus in the time that everyone is speaking about Mars.

Love the concept acronym, which pretty much says it all... Not sure which astronaut would fancy floating around in an atmosphere where clouds are made of sulphuric acid. Besides I don't see the point of a manned mission if one can't reach the surface.. tele-operation would be easy and so much cheaper.

Nice story telling. (watch the video) The materials are actually cool, but the venus flytrap pitch (hinting at a biomimetic success) or the embodied intelligence speech are "a bit" of a stretch,

Sometime in the last few billion years, disaster struck one of Earth's nearest neighbours. Planetary geologists think there is good evidence that Venus was the victim of a runaway greenhouse effect which turned the planet into the boiling hell we see today. A similar catastrophe is almost certain to strike Earth in about 2 billion years, as the Sun increases in luminosity.

the actual paper: http://arxiv.org/abs/1201.1593 just wondering if their conclusion that the long term solution is to change the orbit of Earth is really the ultimate wisdom ...

The Japan Aerospace Exploration Agency spacecraft Ikaros now represents the first solar sail to have harnessed sunlight for both attitude control and propulsion, after it first launched May 21 alongside the Venus-bound orbiter Akatsuki.

Interesting launch, not just the first Japanese Venus [0] mission, also an interplanetary university mission [1] and also a solar sail mission [2]. Looks very interesting ... [0] http://www.jaxa.jp/countdown/f17/index_e.html [1] http://www.unisec.jp/unitec-1/en/about_unitec-1.html [2] http://www.jaxa.jp/projects/sat/ikaros/index_e.html

what a shame! ambition and innovation have not been fairly rewarded ...

I didn't have time yet. But formulating the failure with a MTBF or a FIT, you can easily imagine a more robust solution. Instead of one single burn, you would make several smaller burns - It will take more time and require more fuel though. Another "robust" approach is to consider weak stability boundary capture. Again it takes time, but chances of failure are lessen.

would be a pity indeed!

interesting workshop on language here in Leiden ... Luis, Giusi??

interesting indeed, but the lectures I'd be interested in already took place

No good, 80% of these people are top quoted in my research area... I really should have been there. Evidently the organisers need to work on advertising.

Luckily I'm far away from Geneva, but this has to be said today, when the LHC starts! No, not tiny black holes will eat us (what a nonsense!), but the supernovae energy will let LHC explode!!! Pacome, I expect you to debunk this with gratest care!

Unfortunately, most information I have about the guy (Hans Lehner, a Swiss) is in German, his official homepage is http://www.rqm.ch/ According to EsoWatch he is the Swiss analogue to Dr. Mills and his Blacklight power. Lehner apparently founded a company, which should have produced a "Raum-Quanten-Motor" that -- of course -- produces energy out of nothing. The theory is based on spookey forces mediated by Lehneronen. 11 Million Swiss Franks (about 8 Million Euro) were lost when the company bankrupt. And the guy is selling new stocks on his homepage again... Lehner calls another crackpot named Oliver Crane Zweistein (from Einstein being "Onestone") and himself "Dreistein". Now he is looking for Mister or Misses Vierstein. Perhaps you should apply, good luck!!

i like the first line of their supernovae energy technology document "Dear potential investor:"...

Interesting, but obviously something is wrong. How the big giants can remain still if the inner planets and the sun vanish at the same time !