Some astronomers also have Starship in their eyes. “There’s no way to talk about it without resorting to cliches, but ‘best rocket engine ever,’ probably, by most metrics,” says David Rubin, a cosmologist at the University of Hawaii, Manoa. He wonders how much simpler the $10 billion James Webb Space Telescope (JWST) might have been if its 6.5-meter-wide segmented mirror hadn’t had to fold up to fit on its rocket. Engineers could have built a monolithic mirror and launched it as is within the 9-meter-wide Starship fairing, which encloses a volume about half as big as a hot air balloon.

Rubin also dreams of using Starship to construct a giant telescope—say 30 meters—in space. Limbed robots could precisely lay down mirror segments on a scaffolding, forming a giant mirror that could pick out the universe’s first galaxies and look for signs of life in the atmospheres of Earth-like exoplanets. “The science gains scale really quickly as you build larger and larger telescopes,” Rubin says.

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