A consensus among leading American astronomers is that NASA’s next wave of great observatories should take advantage of game-changing lift capabilities offered by giant new rockets like SpaceX’s Starship.
Launching a follow-on to the James Webb Space Telescope (JWST) on Starship, for example, could unshackle the mission from onerous mass and volume constraints, which typically drive up complexity and cost, a panel of three astronomers recently told the National Academies’ Committee on Astronomy and Astrophysics.
“The availability of greater mass and volume capability, at lower cost, enlarges the design space,” said Charles Lawrence, the chief scientist for astronomy and physics at NASA’s Jet Propulsion Laboratory. “We want to take advantage of that.”
Lawrence’s presentation dealt with the impact of large, new launch vehicles on future astronomy missions. The presentation was given last week alongside Martin Elvis, an astronomer at the Harvard-Smithsonian Center for Astrophysics, and Sara Seager, an astrophysicist and planetary scientist at MIT. Lawrence, Elvis, and Seager authored a paper earlier this year in the journal Physics Today discussing this topic.
It’s widely known that the Starship’s ability to lift more than 100 metric tons into space, at a fraction of the cost per kilogram of existing rockets, would change the way the wider space industry does business. The Starship’s 9-meter diameter (8 meters of the diameter would be usable for a payload) is nearly double the width of the payload volume on any existing rocket.
But astronomers are starting to get serious in planning for rockets like the Starship, or Blue Origin’s New Glenn with a slightly smaller 7-meter payload fairing, to be available to loft the next generation of big space telescopes.
Big telescopes on big launchers
In 2021, the National Academies released a once-in-a-decade review of the top astronomy and astrophysics priorities for the US science community. In this survey, known in shorthand as Astro2020, a distinguished panel of scientists laid out a roadmap for NASA to spend the bulk of the 2020s developing technologies and designs for the next series of “great observatories” that will follow the likes of Hubble, Chandra, James Webb, and the Roman Space Telescope scheduled for launch in 2027.
NASA’s policy is to follow the science community’s recommendations wherever possible. Sometime around the end of the decade, the thinking goes, NASA should be ready to officially kick off development of these new telescopes. First should be a large telescope called the Habitable Worlds Observatory, which would be comparable in size to Webb with a primary mirror around 6 meters (20 feet) across and a coronagraph or a starshade to blot out starlight, enabling direct observations of planets around other stars, or exoplanets. This is a capability not available on Webb.
The Habitable Worlds Observatory, with sensitivity to light in infrared, visible, and ultraviolet wavelengths, would be tasked with observing Earth-like exoplanets in search of worlds that have the makeup to support life. Later, NASA should launch similarly ambitious far-infrared and X-ray telescopes to study the formation of stars, black holes, and galaxies, scientists recommended in 2021.