Explore James Webb Space Telescope Data using Python
Let’s first appreciate the fact that James Webb Space Telescope (JWST) is fully deployed (as of Jan 8th, 2022) and ready to unfold the unknown universe through various observations and science experiments.
JWST is the largest and most complex telescope ever launched into space after years of delays with approximately a $10 billion price tag! Now that it is fully deployed, cruising towards L2 point where it will be permanently stationed and looking back in time, millions or billion light-years! Primary mirror resembles a honeycomb but all the pieces of the mirror need to be adjusted by moving them into their respective positions, in most cases moving a nano millimeter at a time. Once settled in L2 orbit, JWST team plans to spend next 3 months is to configure all the major components before starting any planned or scheduled various observations.
The big difference between HUBBLE and WEBB is their distance from earth. We can still make a trip to HUBBLE to fix any issues and that is not possible in case WEBB due to the 1.5 million kilometers distance from our planet. Before we jump into the Data and Python topic, a quick look at the very basic components of JWST and how it communicates with the ground team.
Deep Space Network (DSN)
JWST communicates through DSN to receive commands and instructions to perform maneuver corrections or experiments and sends telemetry data.
The Deep Space Network is NASA’s international array of giant radio antennas that supports interplanetary spacecraft missions, plus a few that orbit Earth. The DSN also provides radar and radio astronomy observations that improve our understanding of the solar system and the larger universe. DSN’s main role is to collect data, process the data, converts/decode and make it available for the rest of the receiving systems or distribute it. Read more about Ka band here
Learn more about DSN here
This is component is equipped with a number of subsystems to handle electrical power, altitude, communication, command and data handling, telemetry, thermal control and propulsion. This system is actually installed on the warm side of the telescope, facing sun. It is designed to withstand the temperatures due to it’s location on the telescope.
There is a Command Telemetry Processer (CTP), data storage unit and Solid State Recorder (SSR) with a capacity of roughly 59 GB (58.9 GB), less than a standard iPhone storage.
This is pointed towards our planet, used primarily to receive commands and transfer data via Deep Space Network and operates on Ka-band and S-band radio communication with the help of Raytheon ECLIPSE system by Raytheon Technologies, customized to suit NASA’s communication needs.
By definition, telemetry is, self recording and transmitting data to the receiving systems (application) in an automated fashion by a remotely placed physical device or software application. Once the raw data is obtained from various instruments on JWST, raw data is transformed in to a format to perform further analysis.
Simple way to start understanding telemetry concepts are through Phidgets. Phidgets are programmable USB sensors through which we can gather data. I’m very familiar with Temperature Monitor Phidget in my Coffee Roaster, connected through an open source artisan program. Using this sensor allows me to monitor Environment and Beans Temperatures and adjust my coffee roast process to come up with a unique roast profile.
If a physical device is used for telemetry, to collect data of the current state, devices are equipped with a sensor, configured with a destination path to transmit the data, possible display (not necessary), built in software to record and capability to receive commands to control the device. With this kind of characteristics and setup, telemetry devices can be installed/setup in remote locations and that’s what make them more useful.
How remote a telemetry device can be? Approximately 10 Billion miles away from our planet, still sending data and still traveling at amazing speed. Meet Voyager 1!
As mentioned earlier in this article, NASA opted to use Raytheon’s ECLIPSE system, customized to work with JWST to send commands and also to collect telemetry raw data. Once telemetry raw data is obtained there is a separate system aka Data Management System (DMS) to transform telemetry data into more readable formats, FITS, ASDF, ECSV and JSON files.
Once JWST data are obtained, telemetry data from the recorded science data files are received by the Data Management System (DMS) in the same binary format that is stored on the JWST Solid State Recorder (SSR). Then, they are processed to extract the science data and relevant detector and exposure information.
Space Telescope Science Institute (STScl) supports Python for development so most of the Python modules can be installed using pip and supports Conda environment.
If you are familiar with Anaconda distribution, Conda is included in the Anaconda Enterprise. STScl recommends the following steps to work with JWST data, only Linux and MacOS platforms are tested and supported. Unfortunately Windows is not currently supported.
- Install the JWST Science Calibration Pipeline and calibration references files
- Install Astropy
- Install the JWST Data Analysis Visualization Tool, Jdaviz
- Clone the JWST Analysis Notebooks Repo for examples on your local machine
Please visit this link for any latest updates https://jwst-docs.stsci.edu/getting-started-with-jwst-data
Once JWST starts full observations and NASA starts making the transformed data available, we can experiment with the simulated data, available here
Intro to JWST Data Files – https://jwst-docs.stsci.edu/understanding-jwst-data-files
Very interesting part is, you can pick your favorite instrument (MIRI, NIRCam, NIRISS, NIRSpec or Multi-Instrument) on JWST and start learning, exploring and analyze the data to discover more facts or interesting finds about the universe.
For me the most exciting part is, Python and Data Analysis skills can be used to explore the data that is generated around 1.5 million kilometers away from our planet!
Let’s first appreciate the fact that James Webb Space Telescope (JWST) is fully deployed (as of Jan 8th, 2022) and ready to unfold the unknown universe through various observations and science experiments. JWST is the largest and most complex telescope ever launched into space after years of delays with approximately a $10 billion price tag!…