Comment Re:depends. (Score 1) 298
Since February 12, 2014
Since February 12, 2014
They are not using helium as refrigerant, but as pressure transfer medium in a pulse tube for the Stirling cooler. It allows you to decouple the compressor from the cold finger and avoid the need of mechanical piston on the detector side. These detectors typically run between 40 and 80 K, too cold to use nitrogen as transfer gas, hence the use of helium. In any case, the operation range is far from the super cooled case.
No they don't. Thermal imagers typically work around 50 K (based on HgCdTe sensors). This is easy to reach with a portable device, but isn't anywhere close to super-cooled. Higher performance thermal imagers may run at 3 to 4 K, cooled with liquid helium. There you are already far away from the portable solution, and again not even close to super-cooled.
To reach super cooled temperatures (we are speaking of mK, if not uK or nK), you'll need a truck to move the stuff around. Just the ultra high vacuum vessel and the turbo pumps, allowing you to reach vacuum better than in orbit at 200 km altitude, are enough... and you haven't started to cool yet.
It's a reduction from about 2740 Library of Congress to about 120 Library of Congress (assuming the approximate volume of all three LoC buildings).
From TFA :
The reserves were downgraded by 96 percent, from 13.7 billion barrels estimated by a government-funded report in 2011, to just 600 million barrels, the EIA said.
Absolute values help put things into perspective.
Or do we need more perspective? For those who prefer the typical journalistic approach to understanding numbers, it's a reduction from 872'000 Olympic pools to just under 37'200 Olympic pools.
I didn't need to see the source code for Windows 8 to come to the same conclusion...
And why to you assume it is always bitter cold everywhere on Antarctica. All the time. Did TV say that?
Please stop with the half-assed facts. The average temperature of the coldest region of Antractica is -57C. That has nothing to do with the average temperature overall on the continent. What you wrote is just as stupid as saying nobody will get a heat stroke anytime soon in Pheonix; the average temperature in Vail is 11C (52F) after all.
I find it very enjoyable, yet irritating, to see people take every single effect/cause independently, somehow analyse them (while actually having no clue at all what they are doing) and come to the conclusion they are too small to be related to a trend, while missing the obvious point that independent effect can be cumulativ. Worse, different effect can promote other and accelerate the trend. And they cook up a counter arguments (again while having no clue, even of the oders of magnitude) and propagate their ignorance to others ready to believe their pseudo scientific facts.
I really have to stand on the side of other posts I read here, stating that most people are simply not open minded or bright enough to understand the data and analyse it. A large part of this is to blame on education, but when basic logic and analytic skills fail (either due to intellectual capacity or to unwillingness to use those skills) I doupt even that would help.
Maybe the air in Seaworld locations (such as San Diego) is not as good as somewhere in the north pacific ocean.
If you read my initial comment, you'll find the words "... the technology is actually there and ready".
Nobody is arguing about a technological problem.
I do not believe the Aldi - Wallmart comparison is fair. And having lived over 30 years in Canada, I can confirm that there you also find BMW under carports. Not quite as much as here, but a lot...
For the reference, except a few models, BMW cars are expensive as well in Germany. The German tend to invest more on their cars (incl. maintenance). It's something important - which I can understand when you drive usually 150 - 180 km/h (93 - 112 mph) in normal trafic conditions .
I see a lot a of BMW parked under car ports everywhere here in Germany.
(And I still have to see a Walmart)
It might look that simple, but it isn't. Here at least, this is strongly regulated. The only thing you can do without it being a pain is to use the power and stop the meter.
UNIX is hot. It's more than hot. It's steaming. It's quicksilver lightning with a laserbeam kicker. -- Michael Jay Tucker