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Giant sun mirrors were installed to light up one Norwegian town in winter, just to improve the mood of its residents! 

Nice overview and animation of what that means for the Solar system.

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 !

Jere Jenkins and pals at Purdue University in Indiana have re-analysed the raw data from these experiments and say that the modulations are synchronised with each other and with Earth's distance from the sun. (Both groups, in acts of selfless dedication,

NASA's Kepler space telescope could be used to find exomoons, which are the moons of planets orbiting stars other than the Sun. That is the claim of an international team of astronomers, which says that careful analysis of data collected by Kepler could reveal if such exoplanets are circled by moons.

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 ...

Spacecraft equipped with lasers powered by light from the Sun are our best defence against incoming asteroids, say aerospace engineers

The novel part here is that it can be scaled down to the cubesat platform. I then wondered, could we place multiple of such Cubesats in a 'decaying orbit' around the Sun? Fractionated will give spatial and temporal information which, even with a simple langmuir probe setup, can give information on density, temperature, velocity, ion energy distribution, potential.. Of course they will be lost relatively quickly, but more could be ejected from a mother ship which is orbiting at a safer distance.

For example like the KickSat projec https://www.kickstarter.com/projects/zacinaction/kicksat-your-personal-spacecraft-in-space Although a pc-reboot due to a radiation event in the electronics has reset the deployment timeline to approximately 2 days after re-entry... http://www.huffingtonpost.co.uk/2014/05/06/kicksat-satellites_n_5273821.html

Astronomers hunting for another Earth have found what may be the closest match yet, a potentially rocky planet circling its star at the same distance as the Earth orbits the Sun, NASA said Thursday.

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

Well the idea is not really new and cannot explain climate change, but it's interesting

Nice initiative, isn't it?

some citizen science added to this would make it even better ... as it is it's rather, boh ...

Well, true - making data public is one thing, and making others to work through them for you is another... I love the new term "citizen science" though (and an explanation on the Wikipedia page why they had to invent a new one because "crowdsourcing" is soooooo - politically - wrong).

Unexplained annual variations in nuclear decay rates have been reported in recent years by a number of groups. We show that data from these experiments exhibit not only variations in time related to Earth-Sun distance, but also periodicities attributable to solar rotation. Additionally, anomalous decay rates coincident in time with a series of solar flares in December 2006 also point to a solar influence on nuclear decay rates....

can we use space to make a smart experiment to solve this riddle? e.g. sending a decay detecter on a close solar orbit and one to Pluto and then compare decay rates? or a highly elliptical trajectory and compare during peri and apoapsis?

I think it could be possible. I need to look into the details. In fact it could probably be done already with the nuclear generators on the Voyager and Pioneer and other nuclear powered probes. That is if the data are precise enough...

More fascinating Celestial Mechanics stuff...

An atomic physics experiment demonstrates a solution to an eighty-year-old quantum conundrum by mimicking in an atom the astronomical problem of a satellite moving in a sun-earth system. How to stabilize a wave packet?

"When in the desert he came up with the idea to use the two dominating features in the desert -- the sun and the sand -- in his next project.". I wonder where we should send him next.

Arts project with implications for space science... Awesome! Note how this guy is dressed in the middle of an Egyptian desert, lol...

A new mechanism was discovered on how H2 and N2 participate in the radiation budget. This may help to resolve the "faint young sun paradox", a hypothesis according to which during the earlier age of the solar system when sun radiation had lower intensity than now, the earth was warmer. Extended, it could reassess the past habitability of Mars.