One of the earliest great works of literature is The Epic of Gilgamesh. Written on clay tablets, it’s an epic poem from ancient Mesopotamia dating back to 2100 BCE. General recorded human history roughly coincides with the invention of writing around 3-4000 BCE. While there are other ways history can be documented, such as architecture, art and the archeological record, we only have written accounts from about 6000 years of human history.
I find it incredible that I can pick up a book today and read a story written by people over 4000 years ago. In thinking about this though, I wondered: are we doing any better at preserving our written history or modern literature for future millennia? Stone and clay tablets may be about as low-tech as you can get, but they do last. The best hard drive might not even keep data intact for 500 years.
Despite all of our technical prowess, it seems to count for very little in preserving data over the very long term. If we assume that future generations will be able to eventually read any data storage mechanism we have, what are some options and what are the pros/cons?
A hard disk drive stores data magnetically on glass or aluminum platters. These magnetic fields persist even after power is removed, but the fields will decay eventually. It’s difficult to say how rapidly this will occur due to environmental conditions, but some permanent magnets will lose about 1% of their strength about every 10 years. That amounts to a half-life of about 65 years. Yikes. But HDD platters are not permanent magnets, and because the magnetic fields are packed so closely they can contribute to mutual breakdown. Hard drives haven’t really been in existence long enough for us to start seeing these kinds of failures (which will occur long after mechanical failures), but it’s unlikely a hard drive will be able to store data for more than 100 years magnetically without severe data degradation.
SSDs are not much better. They store data with static electrical charges, but these charges, like magnetic fields, will eventually break down. The breakdown will be faster the more writing is done to the device. Because SSDs are an even younger technology than hard disk drives, it’s unclear how long they might be able to last, but I wouldn’t count on more than a few hundred years in ideal conditions.
I’m not painting a very pleasant picture for super long-term data storage here. Are we destined to lose the untold petabytes of data created by modern humans to magnetic and static charge decay? Should we start recording bits to stone tablets?
There is hope. Yes you certainly could record things in stone (and we often still do, if you consider monuments), but data can also be stored long term on quality paper with quality ink. We do have the technology there to make that happen. Thousands of years? Possibly. Personally, though, my preference for very long term data storage is actually a twist on a fairly old technology: vinyl records. It’s a physical storage mechanism, and instead of using vinyl as the material, you can use virtually anything. We could engineer a very hard material, and imprint digital data onto the record physically and if kept in a reasonably stable environment, it should theoretically last forever. NASA thought it was good enough to use when creating the golden record sent with the Voyager space probe. For that record, they used gold-plated copper. Another reason they chose that storage mechanism is that it’s not hard to figure out how to read from it. There are no complicated digital protocols or fleeting interfaces. It could be read any number of ways.
It’s surprising how little our advanced technology can help solve this problem, but I hope that we do. Recording history is the best way for us to keep growing and advancing.