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Foust Forward | Big opportunities for big science with big rockets

SpaceX's Starship/Super Heavy vehicle on the pad prior to its April 20, 2023, launch attempt. Credit: SpaceX

Attendees of this year’s Space Symposium were understandably distracted by what was going on a thousand miles from Colorado Springs. The conference was bookended by SpaceX’s first attempt to launch Starship, scrubbed April 17 because of a frozen valve, and its liftoff on the second attempt three days later. In between, there was plenty of speculation about when it might launch, whether it would be successful and what it meant for the space industry.

Starship has gotten attention for its critical role in NASA’s Artemis lunar exploration campaign and for SpaceX’s own second-generation Starlink constellation. But others are thinking about what Starship and other super-heavy-lift rockets, like Blue Origin’s New Glenn and NASA’s Space Launch System, can do, particularly for science missions.

“Starship can enable next-generation science,” said Julianna Scheiman, director of NASA satellite missions at SpaceX, during a panel at Space Symposium April 18. That comes in part from the sheer payload performance of the rocket. “You can imagine an interplanetary probe or an interstellar probe where you don’t need to track mass by the gram.”

The benefits go beyond mass, though. “It comes down to time, volume and mass,” said John Blevins, NASA SLS chief engineer. The volume comes from the rockets’ larger payload fairings, seven meters or more in diameter. That enables larger spacecraft and reduces the need for deployable systems like those developed for the James Webb Space Telescope.

Time comes from faster transits to distant destinations. “People forget how big the solar system is,” said Louise Prockter, chief scientist for the Applied Physics Lab’s Space Exploration Sector. She has worked on outer solar system mission concepts that require a decade or more of travel time, even for small spacecraft. “That has consequences in terms of power sources and the complexity of the mission.”

All three factors help reduce complexity. “In addition to giving us the opportunity to maybe not fold up the aperture quite as much as we would normally do, it also gives us a lot of volume and mass margin, and that’s very important on these very large missions,” said Mark Clampin, director of NASA’s astrophysics division. He has made the capabilities of such large vehicles one of the guiding tenets for the development of NASA’s next large space telescope, the Habitable Worlds Observatory.

That reduced complexity brings with it the promise of lower costs. Scheiman noted that traditionally there has been a strong correlation between cost and mass of spacecraft: heavier ones cost more. “I can only hope that we can totally break that cost model,” she said, with heavier but less complex spacecraft.

But by how much? Proponents of big rockets are reticent to quantify cost savings. “It’s not something that we can share easily,” said Steve Squyres, a planetary scientist best known for leading the Spirit and Opportunity rover missions who is now chief scientist at Blue Origin.

Asked about those cost savings on the panel, he noted Blue Origin was still developing New Glenn. “We’re taking that very seriously, and time will tell how much we can bring it down.”

Part of that reticence stems from the competitive nature of the launch industry. Still, it would benefit both companies and scientists to work together to publicly quantify how much money can be saved through big rockets. Design studies of even hypothetical missions, such as space telescopes or outer planet orbiters, could show how much complexity, and thus cost, can be saved.

That’s vital given the strains facing NASA’s science portfolio. At the same time as that panel, NASA Administrator Bill Nelson was describing to Senate appropriators the budget challenges his science missions are facing, as cost growth on Mars Sample Return eats into other missions. “In the largest science budget ever, you can’t fit 10 pounds of potatoes in a five-pound sack,” he said.

It’s in the interest of scientists and companies alike to show how the benefits of big rockets can enable big missions, making that five-pound bag a little roomier.

This article originally appeared in the May 2023 issue of SpaceNews magazine.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...