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Comment: Re:Space is hard (Score 1) 223

by 12WTF$ (#48409029) Attached to: Comet Probe Philae To Deploy Drill As Battery Life Wanes

BBC quote follows:
MUPUS the sensor package from the German space agency's Institute for Planetary Research deployed a thermometer on the end of a hammer.
It retrieved a number of temperature profiles but broke as it tried to burrow its way into the comet's subsurface.
Scientists say this shows the icy material underlying 67P's dust covering to be far harder than anyone anticipated - having the tensile strength of some rocks.
It also helps explain why Philae bounced so high on that first touchdown.
The 4km-wide comet has little gravity, so when key landing systems designed to hold the robot down failed at the crucial moment - the probe would have been relying on thick, soft, compressive layers to absorb its impact.
However much dust it did encounter at that moment, it clearly was not enough to prevent Philae making its giant rebound.
[end-quote]
http://www.bbc.com/news/scienc...

Comment: Space is hard (Score 1) 223

by 12WTF$ (#48387783) Attached to: Comet Probe Philae To Deploy Drill As Battery Life Wanes

Comets are now known to be hard as well and definitely not mushy.
THAT is the major finding so far.
Philae was expected to land gently on a frozen snow cone into which it would fire anchoring harpoons,
but it bounced a off a deep frozen ice mass (ouch) ascending 400m then touched down again
then bounced yet again until coming to rest in the shadow of a cliff. Awkward.

Scientists expected the comet’s surface to be powdery, allowing the lander to settle instead of rebounding back into space.

“It’s not a powder, it’s a rock, so it’s like a trampoline,
You go there and it ejects you immediately afterwards.”

The objectives of the science mission will probably be missed because hardware failure and reality trumping assumption.

Comment: Re:Behind a paywall (Score 1) 110

by 12WTF$ (#48054213) Attached to: MIT Study Outlines a 'Perfect' Solar Cell

Hints for paywall circumnavigation:
Google $FirstAuthorsName + $SomeUniquePartOfArticleTitle
Example: Jeffrey Chou Selective Solar Absorption
Scan the results and avoid all that steer back to the paywall.
Find anything? No? That's usual.
Next try adding the $MagicWord = pdf
Example: Jeffrey Chou Selective Solar Absorption pdf
Look carefully at results. Maybe you will find a prepublication copy somewhere?
This will at least give you a flavour of the research work and might tempt you to support the $BILLION science publishing scam^H^H^H^H industry

Comment: Firechat app in Hong Kong. Now. (Score 5, Interesting) 153

by 12WTF$ (#48026029) Attached to: LTE Upgrade Will Let Phones Connect To Nearby Devices Without Towers

Right now, this is happening in Hong Kong:

In Hong Kong, pro-democracy demonstrators are looking for new ways to communicate.

News about the protests in Hong Kong have been suppressed in mainland China, where the picture sharing site Instagram has been blocked. Messages posted to Sina Weibo, a Chinese microblogging site similar to Twitter, are being blocked in far greater numbers than normal. And on Sunday, rumours reportedly circulated that the authorities in Hong Kong might shut down the city's cellular networks.

In response, a different type of social network has come to the fore. The Firechat app allows smartphone users to talk to one another "off-the-grid", in the absence of a mobile signal or access to the internet. By making use of Bluetooth and Wi-Fi, messages are spread in a daisy chain fashion, jumping from one user to the next. The system is particularly effective when large numbers of people are congregated together - like at a music festival, or a political protest.

Micha Benoliel, CEO of Open Garden, the firm that makes the app, tells BBC Trending there has been a huge surge in downloads from Hong Kong, as more than 100,000 new accounts have been created in less than 24 hours. Usage spiked during protests in Taiwan and Iran earlier this year, but never before on this scale, says Benoliel.

Inside the app discussions are arranged either according to theme, or how close you are to other users. At one point on Sunday 33,000 people in Hong Kong were using the app at the same time.

Source: http://www.bbc.com/news/blogs-...

Comment: Re:Plain solar panels cost less (Score 1) 268

by 12WTF$ (#47999023) Attached to: IBM Solar Concentrator Can Produce12kW/day, Clean Water, and AC

Flat mirrors, maybe

Which is what this thing uses.

Nope

Follow the links
http://www.research.ibm.com/la...

The inside of the parabolic dish is covered with 36 elliptic mirrors made of 0.2-millimeter-thin recyclable plastic foil with a silver coating,
which are then curved using a slight vacuum.

http://www.airlightenergy.com/...

A new ultra-high concentration 12 KWel – 20 KWth unit, currently under development, jointly with IBM research Zurich.
The system implements a multi-mirror parabolic dish topology (40 m2 active surface area) and will achieve concentrations beyond 2,000 suns.

Some say 12KWh/day electric cause of the cascading failure of non-engineering descriptions.
I say 100KWh/day electric and 160KWh/day thermal, (it's a beast).
Quoted 12KW electric and 20KW thermal output.
Some math: 40 m2 * 80% * 1KW/m2 = 32KW (consistency check: yep that's 12KW+20KW)
Assume 8hr/day near maximum input because it's tracking the sun.

ALSO: 40m2 area is about 7m diameter.
If you had one in your backyard to run your home:
4m diameter: 30KWh/day el and 50KWh/day th. That's a big big house with many kids (you're Xtian right?)
3m diameter: 17KWh/day el and 28KWh/day th. That's a good fit for most families
2m diameter: 7.5KWh/day el and 12KWh/day th. That's a good fit for singles.

I never cheated an honest man, only rascals. They wanted something for nothing. I gave them nothing for something. -- Joseph "Yellow Kid" Weil

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