How Heavy Is a Petabyte? 495
Posted
by
timothy
from the but-electrons-don't-weigh-anything dept.
from the but-electrons-don't-weigh-anything dept.
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?"
or 2.5" drives? (Score:3, Interesting)
but-electrons-don't-weigh-anything (Score:3, Interesting)
Whatever gave you that idea?
About 2 Kilos (Score:5, Interesting)
Minimum mass of a Petabyte (Score:4, Interesting)
Thinking about the decrease in mass of a petabyte got me thinking about Information Theory and the minimum energy required to store a bit. Or rather, to irreversibly manipulate one bit of information, which I think describes the act of writing to any kind of RAM (disk or otherwise). If I extrapolate that to also mean a mass whose rest energy is sufficient to manipulate a bit, that could give the theoretical minimum mass for a bit of storage. I don't actually know enough information theory to know that value, or even if the comparison from energy of information manipulation to mass of storage is valid, but it struck me as interesting and maybe somebody knows? What's the minimum mass of a petabyte?
A lot heavier than... (Score:5, Interesting)
and a lot bulkier than...
a few strands of DNA.
Re:library of congress (Score:4, Interesting)
Re:Cloud computing-Clouds in Elephant Units (Score:3, Interesting)
Here is an equally interesting piece of news for you: a pile of feathers is heavier than a tank! Of course it all depends on the size of the pile but who can bother with those little details.
Re:MicroSD (Score:5, Interesting)
Technically, if you don't count the hardware to read the data, we could simply remove the hard disk platters from the drive. Since most of the drive's weight is made up of the casing and read electronics, it would probably swing the data/weight ratio back in the favor of hard disks.
Re:library of congress (Score:3, Interesting)
Re:library of congress (Score:4, Interesting)
10,886,216.9 kilograms or 10.9 kilotons is slightly less than one Hiroshima.
So if every book in the Library Of Congress was made of TNT and you detonated them all together, the total yield would be slightly less than one very small atomic bomb. Fuck.
Re:library of congress (Score:3, Interesting)
Re:There is a way! (Score:4, Interesting)
Insightful? Assuming you can perfectly remember 1 byte per second, you'd be memorizing for over 100 million years. The human brain is great and all that, but no way are you going to store that much data while being able to reproduce it later.
Considering a single "frame" of vision for a pair of human eyes is estimated at 576 megapixels (truncating at peripheral vision). We'll imagine that each pixel is assigned a 16-bit hexadecimal value. That means, each time you glance at something, each frame would be calculated at a little more than 1/1000th of a terabyte. The lowball framerate for the human eye is about 18 frames/second (things look fluid). That means that every 50 seconds, your eye is downloading a terabyte of information. He'll absorb it in less than a day through eyesight alone. That doesn't include audio, olfactory, touch, or taste. His brain's data compression will downsize a lot of that information, so it will take him more than a day, but for your i/o ports, taking in a petabyte of information is a daily task.
You'd be hard-pressed to find a living organism that downloads information at 1B/sec
Re:There is a way! (Score:3, Interesting)
Pointless. You could put 1 billion people on a scale and have them all memorize data as fast as they could and the weight won't change (correcting for evaporation, etc.).
-b
About 0.8 micrograms (Score:1, Interesting)
Assuming you represent 1s and 0s as the presence/absence of an atom of aluminum on a sheet one atom thick, then it weighs (at the most, if you store all 1s) about 0.807 micrograms. This all fits onto a sheet of aluminum 1 atom (250 picometers) thick and about 3.35 by 1.67 centimeters in size. Though that would be some impressive hardware that could manipulate that.
Re:No, a bettery wouldn't get any lighter (Score:5, Interesting)
But you are converting mass into energy and energy into mass even in this case, although the amounts are ridiculously small in the case of chemical reactions, which is why conservation of mass is a more than reasonable approximation in chemistry. The mass is stored in the molecular binding energy of the battery's chemicals, and converted into the energy used when the battery discharges. For example, if you weighed very very carefully a bunch of hydrogen gas, a bunch of oxygen gas, and the water you got after combining the two (in a fuel cell reaction, which we can think of as the simplest sort of battery from a chemistry point of view), the water would weigh ever slightly less than the hydrogen and the oxygen, though the difference would be extremely small, since the binding energy difference of a water molecule versus that of hydrogen and oxygen molecules is only a few tens of electron volts, about 10^-35 kg or thereabouts, which amounts to a difference of about a quadrillionth of a gram for one mole of water. For nuclear reactions though, the binding energies we deal with are millions of times greater, and E=mc^2 is much more obvious. For instance, in the nuclear fusion of the two helium-3 nuclei to produce one helium-4 and two free protons, the helium-4 and the two protons weigh less than the original helium-3 nuclei by about 12.86 MeV/c^2, or about 6 milligrams less than if we started with a mole of helium-3 at the beginning of the fusion reaction.