The James Webb Space Telescope captures the universe on a 68GB SSD

With the James Webb Space Telescope (JWST) now up and running and picking up some Amazing Photos, you may be wondering exactly how it is stored. Surprisingly, it has a relatively small SSD drive of 68GB, according to IEEE Spectrum – Enough to handle a day’s worth of JWST images, but no more than that.

While this may seem ridiculously small for a $10 billion satellite, there are several reasons why NASA chose the system. First, JWST is located a million miles from Earth, bombarded with radiation and operating at temperatures well below 50 degrees above absolute zero (-370 degrees Fahrenheit). Therefore, the SSD, like all other parts, must be radiation-reinforced and withstand a complex certification process.

Although not as fast as consumer SSDs, it can still fill up in less than 120 minutes via the telescope’s 48Mbps ICDH subsystem. At the same time, JWST can send data back to Earth at 28Mbps over a 25.9GHz Ka-band connection to the Deep Space Network.

This means that although it collects a lot more data than ever before (57GB compared to 1-2GB per day), it can send all of that data back to Earth in about 4.5 hours. It does this during two communication windows of 4 hours per day, each allowing 28.6GB of scientific data to be transferred. In other words, it just needs enough storage space to collect everyday images – there’s no need to keep them on the telescope itself.

However, there is a mystery. NASA estimates that only 60 gigabytes of storage will be available at the end of the JWST’s 10-year lifespan due to corrosion and radiation – 3% of the drive is used for remote standard and engineering data storage. This will leave a very small margin from JWST, leaving us wondering if it will approach the longevity of Hubble – still going strong after 32 years.