As photographers, we know a thing or two about storage. After all, those precious RAW files can take up a lot of space. So naturally many of us are looking for memory cards with enough capacity to accommodate them all. But surprisingly, the James Webb Space Telescope (JWST) stores all of its data on a single modest 68GB solid-state drive—which is smaller than the SD card currently in my camera. Let’s dive into it.
Related: How to “Focus” a Six-Ton Space Telescope
Will it run out of storage space?
Staying in constant contact with Earth is not possible, so the information gathered by the JWST must live somewhere until it can be discharged. But, if you are wondering if the disk will run out of space, the answer is no, it won’t.
The 68GB capacity seems pretty minimal considering the fact that the very first image was a huge composite of 12.5 hours of exposure, but the truth is that the JWST regularly transmits data before it reaches capacity of storage. In fact, the drive can hold up to 24 hours of information, even when the JWST is producing its maximum amount of data (57 GB per day).
In addition to observational data storage, approximately 3% of on-board storage is reserved for engineering and telemetry data. However, it should be noted that NASA engineers expect the onboard capacity to decrease to around 60 GB after a decade of use due to the extremely low temperatures and high radiation levels in space. With 3% storage announced, could Webb be running out of storage sooner than scientists predicted? It’s hard to say, but NASA engineers seem confident the telescope will hit the 20-year mark.
How it works
JWST data is transmitted via the Deep Space Network (DSN), the same used by Mars rovers, Voyager probes and the Transiting Exoplanet Survey Satellite, among others. The DSN uses three antenna complexes located in Canberra, Australia; Madrid, Spain; and Barstow, California.
Currently, the telescope is 932,000 miles from Earth. To send its data over this entire distance, the JSWT uses Ka band frequencies, a type of microwave on the electromagnetic spectrum that allows transfer speeds of around 28Mb/second. At full capacity, the telescope has the capacity to log up to 57 GB of data per day, compared to 2 GB per day for Hubble.
To obtain data from the JWST, researchers must schedule a contact window up to 20 weeks in advance. The communication channels use the Reed-Solomon error correction protocolalso used in DVDs, Blu-ray discs and QR codes.
While its storage configuration might seem spectacularly unmonumental, the JWST is clearly doing just fine. And we can’t wait to see what he continues to discover!