Deploying the Webb Telescope

An engineer shares what it was like to support the launch and commissioning of the James Webb Space Telescope.

Scarlin Hernandez
Scarlin Hernandez

As a spacecraft engineer who supports the James Webb Space Telescope's Mission Operations Center at STScI in Baltimore, Scarlin Hernandez has not only had a front row seat—she has access to the controls. She supported Webb during its December 25, 2021 launch, and has worked on console throughout its commissioning. Here, she describes what it's like to command the telescope and what her professional future may hold.

Tell me about your work as a spacecraft engineer for the James Webb Space Telescope.

I'm part of the flight operations team in the Mission Operations Center at the institute. My day-to-day varies from on-console shift work, where I'm observing Webb's telemetry, analyzing data, and ensuring health and safety of its spacecraft systems, to working on software products and tools. I also monitor and maintain systems onboard the spacecraft, such as the deployment system, which controlled the motors of the deployments. For example, I helped oversee the antenna, sunshield, and primary mirror wings deploy within the first month after launch.

Prior to launch, I led a couple of wavefront sensing and control integration and testing campaigns. I worked on Webb's Optical Telescope Element, which gathers the light coming from space and sends it to the science instruments. I also helped develop and test the spacecraft unit that controls the actuators [or motors] of the mirrors.

Tell us about Webb's deployments and commissioning. What has it been like so far?

Getting ready for shift work and all of Webb's deployments meant I was adjusting my sleep schedule, meal prepping, and ensuring I was ready to give it my all! Being a part of the deployment team is very special and very rewarding. It has been an honor to work with such incredible engineers. We will forever be bonded by this once-in-a-lifetime milestone.

Supporting the deployments was such a historic moment for humanity—and personally as an engineer and all that I represent. I was sitting on the edge of my seat. Witnessing how beautifully each deployment went after years of hard work was very emotional! I felt like Beyoncé headlining Coachella!

I had coded real-time command scripts, and created and tested operating procedures for Webb before launch. Seeing those scripts being used successfully during deployments was deeply rewarding and humbling. It's almost indescribable.

I remember being the first flight operations team member to put hands on the ground systems in the Mission Operations Center. I was the first to test them. Later on, I started conducting end-to-end data flow tests—sending commands from our systems to the Deep Space Network systems and to the telescope. Finally, I became one of the directors on the last hardware test with the telescope from our Mission Operations Center before it was packed up and shipped out to French Guiana. It was definitely a full circle moment for me.

What's coming up in 2022?

The mission operations team will support the observatory as it cools to operating temperatures. We will also focus the telescope's mirrors, calibrate and finetune the instruments, and make our first discoveries!

What might your work look like after commissioning?

I will still be monitoring telemetry, trending data, performing analyses, providing anomaly support, and maintaining systems onboard the spacecraft, including the actuator drive unit. We will maintain alignment of the telescope throughout the life of the mission, so I will support a range of activities, such as primary mirror segment moves.

Let's back up. Why did you join STScI?

I had been working for a low-Earth-orbit satellite mission at NASA's Goddard Space Flight Center for about four years and decided that I wanted to work for a mission that was going to explore deep space. As I started researching Webb and found out about STScI—which I had never heard of even though I was raised in Baltimore City and attended high school at Baltimore Polytechnic Institute—I decided to apply! The rest is history. I'm coming up on eight years this fall.

What does the future hold for you?

Honestly, I'm excited to see the discoveries we will make with Webb. One of the things that is most fascinating to me is that we will find things that we didn't even know existed! Longer term, I would like to go into project management. I've been rewarded for the relationships I've built with other contractors and my technical contributions to the project. Over the years, I've taken project management trainings offered at STScI, which is nice because I've been able to become a certified Scrum Master. I've also learned a lot on other projects I've led in the past, such as creating a women empowerment program, the first institute-wide diversity, equity, and inclusion program, as well as recruitment campaigns, including the Society of Women Engineers conference and Capitol Technology University's internship program.

Article updated March 2022.