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Another entry by the Planetary Society for the Apollo 11 50th anniversary, this time a podcast series on its political background.

A fifth giant planet was kicked out of the early solar system, according to computer simulations by a US-based planetary scientist. The sacrifice of this gas giant paved the way for the stable configuration of planets seen today, says David Nesvorný, who believes that the expulsion prevented Jupiter from migrating inwards and scattering the Earth and its fellow inner planets.

A fifth giant planet was kicked out of the early solar system, according to computer simulations by a US-based planetary scientist. The sacrifice of this gas giant paved the way for the stable configuration of planets seen today, says David Nesvorný, who believes that the expulsion prevented Jupiter from migrating inwards and scattering the Earth and its fellow inner planets.

a nice recap' of Hayabusa mission

really great visualization

It is an old one, but it was mentioned in some discussion ... Mainly based on this paper https://arxiv.org/abs/astro-ph/0102126

The mantles of Earth and other rocky planets are rich in magnesium and oxygen. Due to its simplicity, the mineral magnesium oxide is a good model for studying the nature of planetary interiors. New work studied how magnesium oxide behaves under the extreme conditions deep within planets and found evidence that alters our understanding of planetary evolution.

Old post from Luis brought back from graveyard..... At least two good ideas to put there: 1) tipping points prediction 2) planetary phases for trajectory transfer and probably many more if we think about it a bit more

space-related kickstarters moving from cubesats to space telescopes. This funding campaign was launched today, and will last for 32 days. They are asking for 1M USD.

"Since the formation of Planetary Resources, our primary goal has been to build technology enabling us to prospect and mine asteroids. We've spent the last year making great leaps in the development of these technologies." - Damn we need to get in touch with these people..!

Let's all start up some crazy space companies together: harvest hydrogen on Jupiter, trap black holes as unlimited energy supplies, use high temperatures close to the sun to bake bread! Apparently it is really easy to do just about anything and Deep Space Industries is really good at it. Plus: in their video they show Mars One concepts while referring to ESA and NASA.

hmm aside from the technological feasibility, their approach still should be taken as an example, and deserve a little support. By tackling such difficult problems, they will devise innovative stuffs. Plus, even if this doom-to-fail endeavour may still seem you useless, it creates jobs and make people think... it is already a positive! Final word: how is that different from what Planetary Resources plan to do? It is founded by a bunch of so-called "nuts" ... (http://www.planetaryresources.com/team/) ! a little thought: "We must never be afraid to go too far, for success lies just beyond" - Proust

I don't think that this proposal is very different from the one by Planetary Resources. My scepticism is rooted in the fact that - at least to my knowledge - fully autonomous mining technology has not even been demonstrated on Earth. I am sure that their proposition is in principle (technically) feasible but at the same time I do not believe that a privately funded company will find enough people to finance a multi-billion dollar R&D project that may or may not lead to an economically sensible outcome, i.e. generate profit (not income - you have to pay back the R&D cost first) within the next 25 years. And on that timescale anything can happen - for all we know we will all be slaves to the singularity by the time they start mining. I do think that people who tackle difficult problems deserve support - and lots of it. It seems however that up till now they have only tackled making a promotional video... About job creation (sorry for the sarcasm): if usefulness is not so important my proposal would be to give shovels to two people - person A digs a hole and person B fills up the same hole at the same time. The good thing about this is that you can increase the number of jobs created simply by handing out more shovels.

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 atom may not be a planetary system, but under specific circumstances it can behave like one. That is the curious finding of physicists in Austria and the US, who have confirmed a 1994 prediction that, in the presence of an applied electromagnetic field, electrons in very highly energized atomic states should behave like the Trojan asteroids of Jupiter.

Bohr's model finally not so wrong?

Link to the paper that is the subject of this article: Olsson-Francis, Karen and Cockell, Charles (2010). Use of cyanobacteria for in-situ resource use in space applications. Planetary And Space Science, 58(10), 1279-1285.http://dx.doi.org/10.1016/j.pss.2010.05.005

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!

Planetary migration poses a serious challenge to theories of planet formation...When multiple planets stir the disk, our simulations yield the new result that large-scale migration ceases. Thus, growing planets do not migrate through planetesimal disks....Although migration through a gaseous disk is an important issue for the formation of gas giants, we conclude that migration has little impact on the formation of terrestrial planets.

Extending quantum communication to space environments would enable us to perform fundamental experiments on quantum physics as well as applications of quantum information at planetary and interplanetary scales. Here, we report on the first experimental study of the conditions for the implementation of the single-photon exchange between a satellite and an Earth-based station. We built an experiment that mimics a single photon source on a satellite, exploiting the telescope at the Matera Laser Ranging Observatory of the Italian Space Agency to detect the transmitted photons. Weak laser pulses, emitted by the ground-based station, are directed toward a satellite equipped with cube-corner retroreflectors. These reflect a small portion of the pulse, with an average of less-than-one photon per pulse directed to our receiver, as required for faint-pulse quantum communication. We were able to detect returns from satellite Ajisai, a low-Earth orbit geodetic satellite, whose orbit has a perigee height of 1485 km.

hello Jose! Interesting it was proposed to do the same with the ISS as part of the ACES experiment. I don't remember the paper but i can look if you're interested

Works for mercury as well.

How much did Apollo cost?