Building the million year disk

Building the million year disk

Summary: Go long with your archive. Not 100 years, not 1000 years, but 1 million years. Here's how it would work.


We store enormous amounts of data today and that is generally a good thing. The problem: we store on disk drives that may last five or six years and may be economic for three.

That is not even a medium-term solution. So researchers have been searching for more.

Whatever intelligent beings follow us may have some interest in the nature of our culture.  This is the goal of the Human Document Project.

Researchers at Hitachi Data Systems recently demonstrated quartz storage, readable by optical microscopes, with an expected life of millions of years. But there is a new entrant in the race for long live storage.

Researchers investigated a tungsten disk encapsulating silicon nitride which should last at least 1 million years. This dwarfs even the 1,000 year DVD.

Why bother?
Homo Sapiens is only a few hundred thousand years old. We may not make it to 1 million years before we either destroy ourselves or evolve into another species. Whoever or whatever intelligent beings follow us may have some interest in the nature of our culture.

This is the goal of the Human Document Project.

The problem
All data is volatile, which means it is not possible to store it forever. Even quartz will eventually wear away.

A long-lasting medium requires a high energy barrier against erasure. Strong thermal stability is key. Researchers found that the required testing temperature to show the data is stable for a million years is 380° Kelvin - a little higher than the boiling point of water.

This led to the choice of tungsten with embedded silicon nitride - transparent to electron beams - as the medium of choice. Tungsten has a high melting point and low thermal expansion. Silicon nitride has a high fracture toughness and a similar thermal expansion.

A related alternative is a medium with high reflection contrast. This is enables much thicker and tougher base since the medium doesn't need to be transparent. The two are similar except for a silicon baseplate:

Screen Shot 2013-11-19 at 7.37.12 PM
Courtesy of the authors.


They propose to write the data using barcodes and QR codes. QR codes can lose up to 7% of the data before becoming unreadable.

Using small QR codes it would be possible to use an optical microscope to read the disk. Embedding even smaller QR codes within each of the larger QR code pixels would dramatically expand the information capacity of the storage.

But the highest storage density would be achieved with electron beam readable media where the embedded silicon nitrite would form the zeros and ones of the code. But this would mean a much thinner and more fragile disk.

When tested the media was able to survive temperatures up to 713° Kelvin which suggests that with further research a true 1 million year disc is possible.

The Storage Bits take.
This is advanced research, not product development. But it points the way to a much more robust long-term digital storage.

Our entire digital civilization rest on persistent digital storage which requires frequent replacement to preserve data. As long as storage densities are increasing this is not a big problem but anything that cannot go on forever won't. And when that happens we will have tough choices to make about what data gets preserved and what doesn't.

If a variation on this technology can be commercialized we may be able to save a lot of energy as well as much of the fabric of our digital civilization. That would be a Very Good Thing.

You can read the paper Towards Gigayear Storage Using a Silicon-Nitride/Tungsten Based Medium by Jeroen de Vries, Dimitri Schellenberg, Leon Abelmann, Andreas Manz and Miko Elwenspoek here (pdf).

Comments welcome, as always. What do you think should be preserved for 1 million years? Miley Cyrus or Beethoven? Or?

Topics: Storage: Fear, Loss, and Innovation in 2014, Storage

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  • Why ?

    Why would you or anyone want a million year disk ?

    Just reliable over a lifetime would be just fine for most people, or a thousand years for say a library.
    • you also do not need to store ALL the data on this

      just the most important stuff and things that do not change much.
      like all history of the planet,
      the science laws and principals to be remebered and such...
      • Re: just the most important stuff

        Who decides which stuff is important? Something that might look like complete junk to you today, might tomorrow be the key to survival of humanity...
      • I would store

        The derp song encoded in FLAC.
    • Yeah

      Still not sure what was the point of this article or the impetus in writing it.
    • Archiving

      I'm guessing some people will comment that archiving will be the driver, however I disagree. If humanity had managed to engineer a million year 5 1/4" floppy disk I'm certain that it's obsolescence would make its purpose moot.
    • Read the link!

      They're talking about preserving the Arts, Sciences and everyday life of now so there would be no guesswork in the future. We know the ancient Egyptians built the pyramids but we have no idea how . . .
    • libraries

      There are libraries that are already thousands years old, as of today. Apparently, whatever you store in a library must last longer.

      Also, it is very true, that when you reach certain information density, you start throwing out stuff. At some point, you throw out stuff that you ought to preserve, as happens today with paper documents. Lots of these are thrown away, without being digitized simply because the libraries are out of storage (for paper books). With digital stuff, even more is thrown out.
  • Overkill

    You only need to store the information for a few generations and expect that future generations will preserve it using their technology for their next few generations.
    Check out patent #7,489,818 for a technology that can get data saved for 500+ years today!
    • RE: Overkill

      The patent assumes a long-term archive medium. The patent covers encoding for long term storage, but not the underlying medium.

      R Harris
  • Why write it?

    Because the topic is interesting in itself. I respectfully suggest that anyone who fails to contrive uses for this has a failure of imagination.
    Otto Schlosser
    • Agreed

      It's discoveries like these that gets us one step closer to the Star Trek TNG memory cube.
  • gravitational field reversal

    we seem to be fine at imagining a future Earth where we can't access our electronic digital data, or at least a future Earth where re-archiving isn't going to happen (Revolution, Walking Dead, WW3 etc), if any of those scenarios happen wouldn't it be good to already have stored important stuff on non-electronic media that can last until the new civilizations can make use of it?
    • Well, possibly.....

      However, how would a future civilization read the stored content?
      It's conceivable that an advanced race previously existed that has been catastrophically wiped out and we have no awareness of them and they chose to encode their civilization's data in granite, yet we've no concept of what to look for or how to read it ....
      • And yet

        Some day we might, so their effort has not gone to waste. If they had not stored their knowledge somehow, we have absolutely no chance to retrieve it, ever.
      • Crystal skull?

        This glaring flashing arrow of symbolism is REALLY blatant to me. But to date, we still haven't been able to abstract information from them.
        Then, it's been only a few decades since they've started to crop up...
        • What's really real?

          Most of the crystal skulls are fakes. How would we know an ancient database isn't a fake too, an electronic Piltdown Man? Eventually computing power will make anything electronic possible, much as CNC has made most any physical object possible.
  • Million year disc

    What is the point of having information stored that long if 1) You do not have the equipment necessary to access the info 2) The method used to read the information is forgotten? Archeologists do not automatically assume that everything they find from a past civilization could possibly be an item with information embedded within. Seems like a pointless exercise!
  • There's always something worth saving.

    OK, a million years is a bit silly, but something with more longevity that the present common technologies would be nice. Maybe all of your photographs are of you making ducklips in front of a mirror, but some folks have photos or historical docs that are truly worth archiving.
    Even a minor improvement in durability would be nice. I don't need a million-year disk any more than I need a race car, but both help drive the technological improvements that help us little guys.
  • So, you've made a Million year storage, now what?

    What is known as the dead sea scrolls were discovered in the late 1940's ish. Believed to be about 2,000 years old. That's nothing compared with a million year storage. Even after that time, not only did almost no one even knew how to read them. Many were destroyed by the people that discovered them. Not even knowing what they were, used as fuel for their cooking fires. Making a million year disk is merely technology. The more importantly should be a method to guarantee they are remembered so they don't end up in a 2K years cooking someones breakfast or not being knowingly destroyed by some future natural catastrophe, dictator or religious zealots like the buddas of bamiyan, the Aztec codex, and the Tikis of the Polynesians as just a few examples