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Comment: Re:Of course, there's this (Score 1) 176

For example, is it the coating on the cells that is wearing out?

Actually, the major factor influencing the life span of photovoltaic panels is the corrosion of the silver metal interconnects.
The plastic backing sheet slowly absorbs water from humidity and breaks down to create corrosive acetic acid.
The fastest breakdown is the hot humid (tropics), the least is cold dry (alpine).
This failure mode has been solved for the newest panels that are made with an impermeable glass back sheet instead of a PVA backing sheet.

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.

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

"If a computer can't directly address all the RAM you can use, it's just a toy." -- anonymous comp.sys.amiga posting, non-sequitir