IN SPACE, NO ONE CAN HEAR YOU OPEN CHRISTMAS PRESENTS

We have entered a new era of wonder in exploring the universe. Launched on Christmas Day 2021, the James Webb Space Telescope (JWST) is the largest optical telescope ever placed outside Earth’s atmosphere and arguably the most complex mechanical structure ever deployed in space. But for years (decades!), I had my doubts.

The project that was eventually to coalesce into the JWST began to take shape as a successor to the Hubble Space Telescope in discussions during the 1990s. But these early conversations did not have consensus (or funding), and were aspirational in nature, not detailed in design. By the time the Next Generation Space Telescope began to take shape, I already had the jaded view that it was a career-bolstering jobs program created by bureaucratic space agencies around the globe. There was a generation of young scientists that were excited about this Hubble replacement, yet I was skeptical that it would ever get off the ground (literally).

Perhaps some of my skepticism was my own emotional attachment to Hubble. Hubble was MY generation’s inspiring mission. It was the “wow” factor that had inspired scientists like me to believe the secrets of the universe were in reach. So part of me was truly sad to see this icon being replaced in the public consciousness. But replaced is the wrong way to think of this. It’s progress. And I’m not saying Hubble was not everything I had internalized it to be for its time. It can be “both / and”. JWST is the logical next step in exploring our universe. But back to the James Webb…

Telescopes are measured by the size of their aperture. Think of a telescope as a bucket that collects light. Just like in a rain shower, if you have a bucket with a wide mouth, you can catch more rain than in a bucket with a narrow mouth. Telescopes with larger apertures (either mirrors or lenses) can collect more light. And the mirror of JWST is big… 6.5-meters-across big! Even by terrestrial (installed on Earth) standards this would be a big telescope! But to put this in space is a crazy idea!

Just how big is 6.5 meters? Well, since you asked, that’s 21 feet across. Taller than the average giraffe; roughly the same diameter as the fuselage of a Boeing 747. It’s 2 basketball-goals-stacked-on-top-of-each-other tall. Take 4 people of average height and have them stand fingertip to fingertip. That is how wide the JWST mirror is.

But why was I so pessimistic about this program? Why the skepticism?

The original NASA design of the late 1990s had a target cost of $1 billion over 10 years of construction. The final design and construction cost ended up being almost $8.8 billion. Wouldn’t you like to go almost 10x over budget and have the government keep funding you? In the late ‘90s, the launch was planned to occur in 2007. By 2007, this date had pushed to 2014. By the time launch came in 2021, there had been so many cost and timing overruns that I didn’t have confidence in the statements of the program administrators. Up until the point of launch, I remained skeptical that the program was anything more than another late, over-budget and under-performing program.

Then came launch on Christmas Day. There was no shortage of press coverage, and everyone loved talking about the “Christmas present” that this was. And while launch is the most visible portion of any space program, it marks the point where things get scary. Not because launch is literally riding a column of fire to space, but because once you’re in space, everything is harder. In all but the most rarest of circumstances (looking at you, Hubble), you relinquish physical access to the asset once it launches. And remember how I mentioned JWST was the most complex mechanical structure ever deployed in space? The JWST is an infrared telescope, which means it is most sensitive when cooled to unbelievably cold temperatures. For this reason, the design team came up with a clever but complex sun shield that has 140 release mechanisms, 400 pulleys, and over 400 meters of cable to deploy 5 human-hair-thick membranes the size of a tennis court. Seriously. None of that is an exaggeration. It’s a crazy idea, and all of this must unfold flawlessly while in space. 

In addition to the sunshield, the mirror of JWST is actually 18 different hexagonal mirror segments with 132 actuators that align the mirror segments to nanometer-level precision. The design team for JWST was bold. You can see the series of carefully orchestrated movements in this animation. (Credit: James Webb Space Telescope YouTube Page.)

My heart started to soften towards JWST shortly after launch. Having been involved in the launch of over 150 satellites, I know how much planning (and terror) goes into each launch. And shortly after the deployment sequence started, it was apparent that the program team knew what they were doing. From my outsider’s perspective, the deployment was flawless. It was measured and deliberate and beautifully choreographed. By the time the satellite reached its final location in space, I was already a convert. 

Then… then… the science started! The images began to be received by the science teams and released to the public, and they exceeded every expectation! Their is absolute wonder and awe abound in these images. They are truly indescribable. I encourage you to explore two links.

The first is a gallery of the initial images released by the JWST team. They are stunning. (Credit: STScI.)

The second is a comparison between Hubble and JWST images of the same objects. (Credit John Ed Christensen.)

Hubble was like walking through an art museum with a candle. You can tell where the art is, and you can appreciate the styles and compositions. But JWST is like walking through a museum in broad daylight, able to see every nuance and stroke and decision by the master artist. For me, I’m not looking at the universe… I’ve been plonked down in the middle of it.

As you have likely guessed, I’ve become a devotee. I’m excited about the James Webb Space Telescope and the things it will teach us about our universe. Most of all, I can’t wait for it to teach us what questions to ask to design the next generation telescope that will come after this. Can you even imagine? I can.