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I am quite amazed that they apparently still use the capsules to return the pictures??? Hard to believe .... "Kobalt spacecraft reportedly carry canisters to return film to Earth during the satellite's mission, which will last at least several months."

tesla announcing home batteries at 350$/kW

Let's do some simple maths... Here in UK, example "economy 7" tarif yields night kWh approx. 12 pence cheaper than during day. Let's say the goal is to store energy equivalent to running a 2kW storage heater for 6 hours during the day. We need 12 kWh, so 12 times $350 this means need to spend approx. 1920 pounds for batteries. Time to break even at ROI: 1920 / 0.12 ~ 7.3 years... And this is assuming using the heater 365 days a year, and quite an expensive tariff (prepaid). SIWB :-)

Also need to take into account that battery capacity tends to go down with time and usage

Interesting! I like the quote "Maybe China would allow that to be a one-way trip but, in Japan, it would have to be a return ticket" talking about a human mission ....

Industry people should not be discriminated when returning to academida. Do we count as industry?

The return of hydrogen fuels??

"Seeking a Human Spaceflight Program Worthy of a Great Nation" - NASA's and Lockheed Martin's 2nd thoughts of returning to the moon..

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

An opinion piece by an ex-Googler, talking, among other things, about how corporate culture is creeping into Google. I've highlighted some snippets which I've found eerily familiar :)

an analysis of implications of the Falcon Heavy announcement

38 degree core body temp in microgravity stabilised after 2 months - due to reduced conv. heat transfer+evaporation https://www.nature.com/articles/s41598-017-15560-w

so that's hypopyrexia (augmented concentrations of interleukin-1 receptor antagonist) AND hypothermia (convection/evaportation)? what puzzles me is that temperatures take so long to return to baseline after astronauts return to earth.

"A platform for public participation in and discussion of the human perspective on machine-made moral decisions" Machine Ethics is basically the return of philosophy through code. Here you can learn a bit about it, and help the MIT collect data on how humans make choices when faced with ethical dilemmas, and how we perceive AIs making such choices.

The researchers used a global climate model to show that if an extreme emissions pathway -- RCP8.5 -- is followed up until 2035, allowing temperatures to rise 1°C above the 1970-1999 mean, and then SRM (Solar Radiation Management) is implemented for 25 years and suddenly stopped, global temperatures could increase by 4°C in the following decades.

Nice quantitative study. They treat the problem within the full uncertainty range of climate sensitivity parameter (much uncertain), very complete. However, at SRM ceasing, after an initial positive spike of Radiative Forcing, the rate of warming seems to return to rates predicted for the non-geoengineering case: "The 20-year temperature trends following SRM cessation are 0.2−0.6 °C/decade for the range of climate sensitivities (figure 5), comparable to those trends that occur under the RCP8.5 scenario without any SRM." I am actually working on a similar idea for deliberate Mars terraforming: aiming to cool the planet down before we introduce a positive Temperature raising feedback with greenhouse gases, maybe could be more efficient than warming itself.

"When a control laser is fired at the crystal, a complex quantum-level reaction turns it the opaque crystal transparent. A second light source is beamed into the crystal before the control laser is shut off, returning the crystal to its opaque state. This leaves the light trapped inside the crystal, and the opacity of the crystal keeps the light trapped inside from bouncing around, effectively bringing light to a full stop." is the simple explanation, but I am not sure how this is actually possible with the current laws of physics

There are two ways to make slow light: material slow light and structural slow light, where you either change the material or the structural properties of your system. Here they used EIT to make material slow light, by inducing transparency inside an otherwise opaque material. As you change the absorption properties of a material you also change its dispersion properties, the so-called Kramers-Kronig relations. A rapid positive change in the dispersion properties of a material will give rise to slow light. To effectively stop light they switched off the control beam, bringing back the opaque state. Another control beam is then used to retrieve the probe pulse that was 'frozen' inside the medium. Light will be halted according to the population lifetime on the energy level (~ 100s). They used an evolutionary algorithm to find an optimal pulse preparation sequence to reach close to the maximum possible storage duration of 100s. Interesting paper!

So it is not real storage then in a sense, as you are stimulating an excitation population which retains the phase information of your original pulse? Still it is amazing that they could store this up to 100s and retrieve it with a probe pulse, but light has never been halted.

During one of these meetings I asked directly whether the government would move to close down the Guardian's reporting through a legal route - by going to court to force the surrender of the material on which we were working. The official confirmed that, in the absence of handover or destruction, this was indeed the government's intention. Prior restraint, near impossible in the US, was now explicitly and imminently on the table in the UK. But my experience over WikiLeaks - the thumb drive and the first amendment - had already prepared me for this moment. I explained to the man from Whitehall about the nature of international collaborations and the way in which, these days, media organisations could take advantage of the most permissive legal environments. Bluntly, we did not have to do our reporting from London. Already most of the NSA stories were being reported and edited out of New York. And had it occurred to him that Greenwald lived in Brazil?

The man was unmoved. And so one of the more bizarre moments in the Guardian's long history occurred - with two GCHQ security experts overseeing the destruction of hard drives in the Guardian's basement just to make sure there was nothing in the mangled bits of metal which could possibly be of any interest to passing Chinese agents. "We can call off the black helicopters," joked one as we swept up the remains of a MacBook Pro.

Whitehall was satisfied, but it felt like a peculiarly pointless piece of symbolism that understood nothing about the digital age. We will continue to do patient, painstaking reporting on the Snowden documents, we just won't do it in London. The seizure of Miranda's laptop, phones, hard drives and camera will similarly have no effect on Greenwald's work.

The state that is building such a formidable apparatus of surveillance will do its best to prevent journalists from reporting on it. Most journalists can see that. But I wonder how many have truly understood

Sarah Harrison is a lawyer that has been staying with Snowden in Hong Kong and Moscow. She is a UK citizen and her family is there. After the miranda case where the boyfriend of the reporter was detained at the airport, can Sarah return safely home? Will her family be pressured by the secret service? http://www.bbc.co.uk/news/world-latin-america-23759834

Now it is too late for Bepi Colombo: most interesting thing on Mercury has been already spotted by NASA.

It is not him guys. Everybody knows he got out of that when the Jedi returned. It must be some other forgotten Jabba's prisoner.

Java is hot again(?) - gotta dig up my old lecture notes.

"A band of space hackers and engineers are trying to do something never done before - recover a 36 year old NASA spacecraft from the grips of deep space and time. With old NASA documents and Rockethub crowdfunding, a team led by Dennis Wingo and Keith Cowing is attempting to steer ISEE-3, later rechristened ICE, the International Cometary Explorer, back into an Earth orbit and return it to scientific operations. Dennis says, 'ISEE-3 can become a great teaching tool for future engineers and scientists helping with design and travel to Mars'. Only 40 days remain before the spacecraft will be out of range for recovery. A radio telescope is available, propulsion designs are in hand and the team is hoping for public support to provide the small amount needed to accomplish a very unique milestone in space exploration

The device, like dolphins, sends out two pulses in quick succession to allow for a targeted search for semiconductor devices, cancelling any background "noise",

Could it be used to measure ocean acidification? I found a study that links sound wave propagation with ocean acidity. Maybe we are able to do such measurement from space even? "Their paper, "Unanticipated consequences of ocean acidification: A noisier ocean at lower pH," published last week in the journal Geophysical Research Letters, found that fossil fuels are turning up the ocean's volume. Since the beginning of the Industrial Revolution, the overall pH of the world's oceans has dropped by about 0.1 units, with more of the changes concentrated closer to the poles. The authors found that sound absorption has decreased by 15 percent in parts of the North Atlantic and by 10 percent throughout the Atlantic and Pacific"

The last time I asked an oceanographer for the use of acoustic waves, she said it is still a bit problematic method to take into account its data, but we were referring to measuring ocean circulation. It may be more conclusive for PH measurements, though. The truth is that there is a whole underwater network with pulse emmitters/receivers covering the North Atlantic basin, remnant infrastructure for spying activities in the WW2 and in the cold war, that stays unexploited. We should look more into this idea

DuckDuckGo is a search engine that does not track you and, has more instant answers and less spam/clutter. You can still search google hits by added !g to your search query, which will then send an encrypted search request to google and return only the sensible part

!w = Wikipedia !wa = Wolfram alpha !y = Yahoo