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ARCA is the romanian google X prize competitor.

I like the 4 stage system. But how did they solve the plume issue ?

The plume issue is not that difficult. I think they used something similar on Apollo LES. The problem is stabilizing the entire system, which is extremely difficult. The entire system will most likely plummet down after the solar balloon phase (which is the only phase they tested before). At least they are not using government money :).

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 !

The integrated total reflectance from carbonnanotube arrays is three times lower than the lowest-ever reported values of optical reflectance from any material, making it the darkest man-made material ever.

Next astronaut suit: Electronic systems that offer elastic mechanical responses to high-strain deformations are of growing interest because of their ability to enable new biomedical devices and other applications whose requirements are impossible to satis

Did you know about this Weather Modification Office? Promising or dodgy?

Yes. In China it happens apparently quite often that weather is regionally modified, e.g. in order to have good weather conditions during certain events (like olympics in Beijing). But also in other countries weather modification is applied, for reasons of agriculture, pollution, skiing, etc. Obviously, one wonders on the environmental impact of such an artificial cloud feeding process with silver iodide. I just googled, stumbling upon this report http://www.weathermodification.org/AGI_toxicity.pdf which published the result: no environmentally harmful effects...

and w.r.t. ur question: I mean different weather conditions which we experience locally (like droughts or other extreme weather events) are (often) due to large-scale/global climatic changes. Hence, cloud seeding just describes a local, short-term mitigation of these events. However, there is a geoengineering proposal (so climate modification) which also suggests to seed clouds above the sea (i.e. increase cloud coverage, e.g. by using seaspray as cloud condesation nuclei), thereby increasing the planetary albedo (Earth reflectance) and reducing the energy reaching the Earth surface. If this idea is promising or not, I couldn't judge upon, but for sure it is worthwhile to take a closer look at.

even confining spatially harmful phytoplankton blooms, away from coastal areas

An exhaustive overview of all possible advanced rocket concepts, eg.. "As an example, consider a photon rocket with its launching mass, say, 1000 ton moving with a constant acceleration a =0.1 g=0.98 m/s2. The flux of photons with E γ=0.5 MeV needed to produce this acceleration is ~1027/s, which corresponds to the efflux power of 1014 W and the rate of annihilation events N'a~5×1026 s−1 [47]. This annihilation rate in ambiplasma l -l ann corresponds to the value of current ~108 A and linear density N ~2×1018 m−1 thus any hope for non-relativistic relative velocity of electrons and positrons in ambiplasma is groundless." And also, even if it would work, then one of the major issues is going to be heat dispersal: "For example, if the temperature of radiator is chosen T=1500 K, the emitting area should be not less than 1000 m2 for Pb=1 GW, not less than 1 km2 for Pb=1 TW, and ~100 km2 for Pb=100 TW, assuming ε=0.5 and δ=0.2. Lower temperature would require even larger radiator area to maintain the outer temperature of the engine section stable for a given thermal power of the reactor."

The problem is not achieving a high energy density, that we can already do with nuclear fission, the question however is how to confine or harness this power with relatively high efficiency, low waste heat and at not too crazy specific mass. I see magnetic confinement as a possibility, yet still decades away and also an all-or-nothing method as we cannot easily scale this up from a test experiment to a full-scale system. It might be possible to extract power from such a plasma, but definitely well below breakeven so an additional power supply is needed. The fission fragments circumvent these issues by a more brute force approach, thereby wasting a lot of energy for sure but at the end probably providing more ISP and thrust.

Sure. However, the annihilation based photon rocket concept unifies almost all relevant drawbacks if we speak about solar system scales, making itself obsolete...it is just an academic testcase.

In Interstellar, the science-fiction film out this week, Matthew McConaughey stars as an astronaut contending with a supermassive black hole called Gargantua. The film's special effects have been hailed as the most realistic depiction ever made of this type of cosmic object. But astrophysicists have now gone one better - this is a really cool visualisation done by researchers in Cornell.

Wow, impressive! Simulating eXtreme Spacetimes (SXS) software, very quick merging process though 17ms.. Observable?

Mind-blowing!

Cornell applied physicists have demonstrated an unprecedented method of control over electron spins using extremely high-frequency sound waves - new insights in the study of the spin of the electron. Crazy idea but, no further need for complicated quantum encryption techniques of sound signals?

A new so called 5D data storage that could potentially survive for billions of years. The research consists of nanostructured glass that can record digital data in five dimensions using femtosecond laser writing.

Yes Alex, indeed, the durability is the point I think they highlight and focus on (besides the fact the abstract says something as the extrapolated decay time being comparable to the age of the Universe..). Indeed memories face problems with retention time. Most of the disks retain the information up to 10 years. When enterprises want to store data for longer times than this they use... yeah, magnetic tapes :-). Check a interesting article about magnetic tape market revival here http://www.information-age.com/technology/data-centre-and-it-infrastructure/123458854/rise-fall-and-re-rise-magnetic-tape I compared for fun, to have one idea of what we were talking about. I am also very curious so see the writing and reading times in this new memory :)

But how can glass store the information so long? Glass is not even solid?!

Bio-hacking/cyborg: implanting rare-earth magnets into your fingers to sense magnetic fields. At the same time quite awesome and quite extreme.

Genetic algorithms are a competitive alternative for training deep neural networks for reinforcement learning. For paper see: https://arxiv.org/pdf/1712.06567.pdf

Interesting pointers in this one! I would like to explore neuroevolution as well, although it seems extremely resource-demanding?

Not necessarily, I think it can be made to be much faster hybridizing it with backprop and Taylor maps. Its one ideas in the closet we still have not explored (Differential Intelligence: accelerating neuroevolution).

The best paper on transformation optics written ever :-)

Concerning the fabrication... as usual, no idea. I agree that this is the main drawback of MM, and certainly difficult to overcome. I would double check that number, because its value is related with the beam shape of Fig. 1 A. I believe that the simulations are correct, it's just a detail.

wow ... still publishing despite babysitting and new job!!

One overview about a recent publication (10/06/2014 http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.112.236802) showing room temperature operation of a new type of laser 'discovered' in 2013, the polariton laser. This new type of laser shows extremely low threshold current density - 2 orders of magnitude below Vertical Cavity Surface Emitting Lasers (VCSEL) - and it is believed to become one important component of nanophotonic integrated components.