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How Heavy Is a Petabyte?
Jon Morgan writes "Whilst heaving around numerous data storage systems to sell (they weigh A LOT!), we got to wondering: How heavy is a Petabyte of data storage? Our best guess is 365KG, which is 6 million times lighter than in 1980! But is there a lighter way to store a Petabyte?"
...weighs something like 300mg/card. That's 48GB/gram, or a bit over 20g/TB, or 20Kg/PB.
According the Library of Congress' website they have approximately 32 million books. A bit of googling turned up that an average book weight about 12 ounces. So, 32 million * 12 ounces = 10,886,216.9 kilograms
A common misconception, and just saying it on Slashdot doesn't make it true. Clouds weigh more than elephants - much more. In fact, you can learn the weight of clouds in elephant units here.
Not only that, but clouds are usually darker than the air around them.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
That was my dissertation topic, conventional systems require ~kT per bit (k is the Boltzmann constant = 1.3806503 Ã-- 10-23 m2 kg s-2 K-1 and T is the temperature of the gate in Kelvin) for each read. Quantum systems can access well below that by various trickery (single photon optical computers can reduce this by a thousandfold). In theory a individual photon can hold huge amounts of data in it's state vector before collapse. The trick is making a measurement on enough of these photons to extract the info you need while overcoming shot noise.