Peering Into the Past and Redefining the Future With Space Telescopes

Humanity has always looked to the stars. You could say that stargazing is a connecting thread throughout our collective history. From Earth’s oldest cave paintings to Galileo’s discoveries in the 1600s and beyond, the stars have long inspired and aided human society.

Now, centuries later, our capacity to learn about the stars and the universe around us has seen a meteoric rise. Advances in optical engineering and the deployment of ground- and space-based telescopes will help us see farther than ever before.

Let’s explore two advanced space telescopes that enable global scientists to expand our understanding of the universe: the James Webb Space Telescope and the Nancy Grace Roman Space Telescope.

Space Superstars: The James Webb and Nancy Grace Roman Space Telescopes

Before the Hubble Space Telescope launched in 1990, scientists were already wondering what would be next. According to NASA, conversations about what would become the James Webb Space Telescope (also known as Webb or JWST) began in 1989.

While Webb follows in Hubble’s footsteps and complements its work, it is unique in a few key ways. For instance, Webb:

• Orbits the Sun instead of Earth
• Is optimized for infrared wavelengths, which results in longer wavelength coverage that enables it to see colder, older things in the universe and points of interest that can’t be observed with ground-based telescopes
• Pioneered critical technological advancements, such as:
  • A folded primary mirror that can fit in the rocket and is comprised of 18 hexagonal segments that, when precisely tuned to act as a single surface, are capable of collecting six times more light than Hubble
  • An unfolding extra-efficient sunshield and passive cooling to avoid having a lack of coolant end its mission
  • How to launch the largest (at the time) foldable telescope into space and ensure that it could self-assemble

Webb launched Dec. 25, 2021, with high hopes of expanding our knowledge of the universe and serving as the premier observatory of the next decade. Through Webb, astronomers around the world can study our universe’s history. This includes exploring everything from the Big Bang and the life cycles of stars to the formation of solar systems that can support life.

While Webb is still actively changing how we view our world, in the great tradition of space telescopes, the next big thing is already on the way. Named after NASA’s first chief astronomer, the Nancy Grace Roman Space Telescope (also known as Roman) was adopted by NASA in 2010 and is currently expected to launch no later than May 2027.

From the outset, Roman differs from Webb in a few ways. For instance, it had an interesting start when the National Reconnaissance Office (NRO) offered a spy satellite for repurposing in cosmological research. As for its core science, the Roman telescope sees in the visible and near-infrared, similar to Hubble. However, Roman’s field of view will be around 100 times larger than Webb's, which will help to complement Webb’s existing capabilities to see deeper into space. This means that Roman’s findings can select areas for Webb to investigate more closely.

As for what is catching Roman’s “eye,” the goals of this telescope include observing the universe to learn more about dark matter, dark energy, cosmic expansion over time, exoplanets, and completing the Galactic Plane Survey, which will map around 20 billion stars and aid in creating the most advanced picture of the Milky Way’s structure to date.

To achieve these goals, Roman, like its predecessors, will also rely on advanced technologies, such as its 300-megapixel infrared camera wide-field instrument and a high-performance coronagraph. Crucial technological innovations for Roman include extreme lightweighting of the primary mirror and an advanced array of detectors to cover the large field of view.

How Silicon, Simulation, and Systems Help Space Telescopes Excel

Before Webb and Roman can pull off these amazing feats, engineers must first create optimized designs that can thrive in space. Designs must be rad-tolerant, safe, secure, and capable of deploying the latest innovative technology, while also reducing weight, minimizing costs, and ensuring that timelines are met.

Adding to this complexity is the fact that Roman and Webb are designed to be deployed around a million miles from Earth. Webb orbits Sun-Earth Lagrange point 2 (L2) and Roman will also observe from L2. While this location provides a few key benefits, including enabling the telescopes to stay in line with Earth as it moves around the Sun and blocking out most of the light and heat coming from the Sun and Earth, it also means they cannot be repaired by an astronaut if something goes wrong. Instead, their designs must be flawless by the time they reach the launch pad.

The complex designs of these space telescopes make this an incredible challenge. For example, the entire optomechanical assembly must be folded for launch and then deployed in space. Ensuring that this can happen successfully involves considering the vacuum of space, radiation, thermal changes, vibrations, and more — all from Earth.

This is where companies like Synopsys come in. Synopsys has a long history of working as a contractor for government partners, and Ansys, part of Synopsys, is another helpful solution provider for space telescopes like Webb and Roman. As Jeff Baxter, director of application engineering at Ansys Government Initiatives (AGI), says, “simulation is critical to getting things First Time Right, especially in space because you only have one chance.”

One way that Ansys simulation solutions can make the most of this one chance is during the testing and development phases. For instance, Webb could not be fully tested in the zero gravity and extremely cold temperatures of space. So how could engineers be sure it would survive an L2 orbit using Earth-based testing?

“Simulations had to bridge the gap,” says Erin Elliott, principal R&D engineer at Ansys. Those working on space telescopes can use simulation solutions to accurately design and verify system performance. Elliott knows this firsthand, since she was part of the team that developed the software and hardware for Webb's primary mirror alignment.

Here, Elliott heavily relied on Ansys Zemax OpticStudio optical system design and analysis software. Elliott shared in an interview with Engineering.com that she used OpticStudio software for tasks such as testing best- and worst-case scenarios to align Webb’s 18 segments perfectly so that they could function like a single mirror. Elliott and her team used OpticStudio software to simulate the complex optics of Webb in the absence of a full-scale model, enabling efficient and accurate testing in a virtual space environment.

This was of the highest importance, since Webb’s mirrors needed to be developed with extreme precision, including making changes as small as the width of a virus to optimize the design, says Adam Gorski, director of national security solutions at Ansys, part of Synopsys.

In the years since Webb’s development, OpticStudio software has been updated to include an application programming interface (API) that “makes it easy to embed it in your simulations … so you can run one big simulation,” says Elliott. Other helpful updates include the introduction of the structural, thermal, analysis, and results (STAR) tool, which enables thermal and structural deformation data to be directly added to optical models, as well as improved analysis and handling for off-axis mirrors and manufacturability considerations. These updates will make creating the next great space telescopes even easier.

OpticStudio software has also been used to simulate a spot diagram as part of the characterization of Roman's slitless spectrometer, for a study on Roman's wide-field instrument's compact prism assembly for slitless spectroscopy, and more.

This is just the start of how Synopsys can help space telescopes achieve their missions. As Elliott says, “all space telescopes have some things in common,” and could benefit from using:

• Ansys Systems Tool Kit (STK) digital mission engineering software and Ansys Orbit Determination Tool Kit (ODTK) orbital measurement processing software as critical parts of a flight dynamics system, to build complex design reference missions (DRMs), to design trajectories, to perform operational orbit determinations, and more
• Ansys Thermal Desktop thermal-centric modeling software to simulate and verify thermal predictions on the delicate heat-sensitive instruments on space telescopes
• Ansys Mechanical structural finite element analysis software to find solutions to the precise mirror pointing and analyze the critical support structure

Additional solutions that can assist the innovators designing and developing space telescopes include Ansys HFSS high-frequency electromagnetic simulation software, Ansys ModelCenter model-based systems engineering software (as seen in this example), and the Ansys System Architecture Modeler (SAM) capability.

From systems to silicon, every piece of a space telescope must be confidently designed to exist in the harsh space environment. Our products have and will continue to enable researchers to strike this balance. For instance, the combination of Ansys simulation solutions with chips designed using Synopsys products will enable engineers to efficiently design and optimize for the space environment by using trusted products that can be found in one place.

These solutions are more than just helpful; they are imperative to succeeding in space. As Gorski puts it, Webb “was one of the hardest endeavors in all of human history, and it really wouldn't have been possible without Ansys software.”

From Peering Into Our Mysterious Past To Making Discoveries That Can Change Our Future

The impact of space telescopes extends from solving some of the universe's earliest mysteries to inspiring the next generation of scientists.

“(Webb) is giving us clearer views of things that we've already understood, but because it's looking at the infrared part of the spectrum, we're seeing things that we could never see before,” says Gorski. “It's completely transformed the developmental models of the universe … and is giving us a window into other worlds and into the creation of the universe that we're all a part of.”

Webb and Roman aren’t the only space telescopes making a big impact, either. The upcoming Habitable Worlds Observatory (HWO) will search for signs of life on planets orbiting different stars, while also facilitating astrophysics research.

While the achievements and findings gained from space telescopes may seem removed from our day-to-day existence — they are literally happening millions of miles away — they have a tangible impact on our lives and in advancing key technologies. The technologies developed to ensure these telescopes succeed in their missions can also help advance satellites and will result in advancements in a wide range of Earth-based industries, including the automotive, medical, and robotics fields. In this way, these same space technologies are powerful enough to support many aspects of modern life, from GPS to weather prediction, not just the study of the stars.

And this is only the start. As humanity has always looked to the stars, we will continue to do so — we’ve only explored a tiny part of our universe after all. Space telescopes and solutions from Synopsys enable mission success that will help us make new discoveries across time.

Solutions from Synopsys in the space industry and beyond, can help innovators make these discoveries, enabling us to better understand not only our past, present, and future but our place in the universe.

Disclaimer: NASA was not involved in the creation of this article and did not endorse the use of images in this article.