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In a surprise announcement earlier today (July 13), the European Southern Observatory said that monster black holes - those giants of millions or billions of solar masses, thought to lurk at the hearts of most galaxies - have a mechanism to become active other than galaxy collisions.

"A new study combining data from ESO's Very Large Telescope and ESA's XMM-Newton X-ray space observatory has turned up a surprise. Most of the huge black holes in the centers of galaxies in the past 11 billion years were not turned on by mergers between galaxies, as had been previously thought." and "The process that activates a sleeping black hole - turning its galaxy from quiet to active - has been a mystery in astronomy. What triggers the violent outbursts at a galaxy's center, which then becomes an active galactic nucleus? Up to now, many astronomers thought that most of these active nuclei were turned on when two galaxies merged, or when they passed close to each other and the disrupted material became fuel for the central black hole. Results of the new study indicate this idea may be wrong for many active galaxies." very interesting indeed

looks like very nice research - can we implement a technique inspired by this on a landing spacecraft?

Good to solve the Landing problem!!!! No skew due to perspective and gimballed by definition

Very very nice idea! Unfortunately samples show they still have quite some work to do on the image processing side... which is interesting because there are very good open-source solutions for stitching.

Quantum chemical simulations reveal an unprecedented relationship between the mechanism of carbon nanotube growth and hydrocarbon combustion processes. Results of these simulations illustrate the importance in the role of carbon chemical bonding and molecular transformations in CNT growth.

In the space industry, concurrent design is frequently implemented as requirements are frequently not set but developed along the design process. In many cases this is due to the interconnection between (sub)systems. In the industry however, this is hardly done, but it is becoming more relevant as lead times and innovation speed needs to increase. There is a webinar tomorrow 10 december from Agile on this topic regarding the semiconductor industry

missed it ... did anybody attend?

Ever wondered what radiation looks like? If you have, I bet you didn't think it would look as cool as this. This is a small piece of uranium mineral sitting in a cloud chamber, which means you can see the process of decay and radiation emission....

Once I saw a DIY spark chamber in LIP (CERN associated laboratory). It was the work of a bunch of BSc students, they made it all from scratch, so it seemed to be not that difficult to have one at home. Yet another project for the future 'Experimental Physics' stagiare maybe :)

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!

Software that roughly mimics the way the brain works could give smartphones new smarts-leading to more accurate and sophisticated apps for tracking everything from workouts to emotions. The software exploits an artificial-intelligence technique known as deep learning, which uses simulated neurons and synapses to process data.

First peer review study about he criticality of rare-earth metals. It can be read "They found that supply limits for many metals critical in the emerging electronics sector (including gallium and selenium) are the result of supply risks. The environmental implications of mining and processing present the greatest challenges with platinum-group metals, gold, and mercury. For steel alloying elements (including chromium and niobium) and elements used in high-temperature alloys (tungsten and molybdenum), the greatest vulnerabilities are associated with supply restrictions" Questions about estimation apart, this can be a valuable market for asteroid mining.. (ot just more market for Infinium-like companies http://www.technologyreview.com/news/527526/a-cleaner-cheaper-way-to-make-metals/).

Here we explore the electrochemical performance of pyrolyzed skins from the species A. bisporus, also known as the Portobello mushroom, as free-standing, binder-free, and current collector-free Li-ion battery anodes. At temperatures above 900 °C, the biomass-derived carbon nanoribbon-like architectures undergo unique processes to become hierarchically porous. Basically they burned a Portobello mushroom and used it as a battery... now thats an multidisciplinary advanced concept

very nice! "For a start, the wires operate well as switches that by some measures compare well to field effect transistors. For example they allow a million times more current to flow when they are on compared with off when operating at a voltage of about 1.5 V. "[A light effect transistor] can replicate the basic switching function of the modern field effect transistor with competitive (and potentially improved) characteristics," say Marmon and co. But they wires also have entirely new capabilities. The device works as an optical amplifier and can also perform basic logic operations by using two or more laser beams rather than one. That's something a single field effect transistor cannot do."

any idea how the shine the light selectively to such small surfaces?

"Illumination sources consisted of halogen light, 532.016, 441.6, and 325 nm lasers ported through a Horiba LabRAM HR800 confocal Raman system with an internal 632.8 nm laser. Due to limited probe spacing for electrical measurements, all illumination sources were focused through a 50x long working distance (LWD) objective lens (N.A. = 0.50), except 325 nm, which went through a 10x MPLAN objective lens (N.A. = 0.25)." Laser spot size calculated from optical diffraction formula 1.22*lambda/NA

Researchers have managed to create a materials that can extract CO2 from a humid environment, which was up to now not possible due to water blocking the absorption. With this hurdle taken, it may be possible to extract CO2 in large quantities from the atmopshere. This would then either be stored or possible even processed with H2 to form carbohydrates. Marsian atmosphere?

Exercise can enhance the development of new brain cells in the adult brain, a process called adult neurogenesis. These newborn brain cells play an important role in learning and memory. A new study has determined that mice that spent time running on wheels not only developed twice the normal number of new neurons, but also showed an increased ability to distinguish new objects from familiar objects.

wow ... time to start running again ...

my old question: how could we use it for space?

It will depend on the alloys used, I am not sure but bainite might magnetic and I am not sure if nickel alloy based (stainless) steels can be processed at this low temperature... Metallurgist RF?

What happens if you put a TV in the maze your robot is supposed to navigate (driven by curiosity)?

Does the fact that I follow this process of learning, make me a meta-learner? Or a pre-robot?

Norwegian scientist Kristian Morten Olesen has patented a process to mix nano-particles of clay with water and bind them to sand particles to condition desert soil - he has been working on Liquid Nanoclay (LNC) since 2005.

The news here that some patent has been filed. If it actually works the guy is an ass for wanting to patent something that is solving world hunger. If it does not, then the guy is still an ass. So the news is that this guy is an ass :)

Agreed :) But, if it does work I doubt the guy will be able to enforce the patent in most of the countries where this will be helpful.

Need to tap into a python session? Look no further!

How do humans construct their mental representations of the passage of time? The universalist account claims that abstract concepts like time are universal across humans. In contrast, the linguistic relativity hypothesis holds that speakers of different languages represent duration differently. The precise impact of language on duration representation is, however, unknown. Here, we show that language can have a powerful role in transforming humans' psychophysical experience of time. Contrary to the universalist account, we found language-specific interference in a duration reproduction task, where stimulus duration conflicted with its physical growth. When reproducing duration, Swedish speakers were misled by stimulus length, and Spanish speakers were misled by stimulus size/quantity. These patterns conform to preferred expressions of duration magnitude in these languages (Swedish: long/short time; Spanish: much/small time). Critically, Spanish-Swedish bilinguals performing the task in both languages showed different interference depending on language context. Such shifting behavior within the same individual reveals hitherto undocumented levels of flexibility in time representation. Finally, contrary to the linguistic relativity hypothesis, language interference was confined to difficult discriminations (i.e., when stimuli varied only subtly in duration and growth), and was eliminated when linguistic cues were removed from the task. These results reveal the malleable nature of human time representation as part of a highly adaptive information processing system.

This has been around for over a year. The current trend in deep learning is "deeper is better". But a consequence of this is that for a given network depth, we can only feasibly evaluate a tiny fraction of the "search space" of NN architectures. The current approach to choosing a network architecture is to iteratively add more layers/units and keeping the architecture which gives an increase in the accuracy on some held-out data set i.e. we have the following information: {NN, accuracy}. Clearly, this process can be automated by using the accuracy as a 'signal' to a learning algorithm. The novelty in this work is they use reinforcement learning with a recurrent neural network controller which is trained by a policy gradient - a gradient-based method. Previously, evolutionary algorithms would typically be used. In summary, yes, the results are impressive - BUT this was only possible because they had access to Google's resources. An evolutionary approach would probably end up with the same architecture - it would just take longer. This is part of a broader research area in deep learning called 'meta-learning' which seeks to automate all aspects of neural network training.

Btw that techxplore article was cringing to read - if interested read this article instead: https://research.googleblog.com/2017/05/using-machine-learning-to-explore.html