Read an article the other day about scientists creating an optical disk that would be readable in a million years or so. The article in Science Mag titled A million – year hard disk was intended to warn people about potential dangers in the way future that were being created today.
A while back I wrote about a 1000 year archive which was predominantly about disappearing formats. At the time, I believed given the growth in data density that information could easily be copied and saved over time but the formats for that data would be long gone by the time someone tried to read it.
The million year optical disk eliminates the format problem by using pixelated images etched on media. Which works just dandy if you happen to have a microscope handy.
Why would you need a million year disk
The problem is how do you warn people in the far future not to mess with radioactive waste deposits buried below. If the waste is radioactive for a million years, you need something around to tell people to keep away from it.
Stone markers last for a few thousand years at best but get overgrown and wear down in time. For instance, my grandmother’s tombstone in Northern Italy has already been worn down so much that it’s almost unreadable. And that’s not even 80 yrs old yet.
But a sapphire hard disk that could easily be read with any serviceable microscope might do the job.
How to create a million year disk
This new disk is similar to the old StorageTek 100K year optical tape. Both would depend on microscopic impressions, something like bits physically marked on media.
For the optical disk the bits are created by etching a sapphire platter with platinum. Apparently the prototype costs €25K but they’re hoping the prices go down with production.
There are actually two 20cm (7.9in) wide disks that are molecularly fused together and each disk can store 40K miniaturized pages that can hold text or images. They are doing accelerated life testing on the sapphire disks by bathing them in acid to insure a 10M year life for the media and message.
Presumably the images are grey tone (or in this case platinum tone). If I assume 100Kbytes per page that’s about 4GB, something around a single layer DVD disk in a much larger form factor.
Why sapphire
It appears that sapphire is available from industrial processes and it seems impervious to wear that harms other material. But that’s what they are trying to prove.
Unclear why the decided to “molecularly” fuse two platters together. It seems to me this could easily be a weak link in the technology over the course of dozen millennia or so. On the other hand, more storage is always a good thing.
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In the end, creating dangers today that last millions of years requires some serious thought about how to warn future generations.