A Starshade Test Turns Exoplanet Imaging Into a Navigation Challenge

Engineers are studying how a free-flying screen could align with a telescope precisely enough to dim a distant star.

Written by: Mara Chen
Published: June 24, 2026
Reading time: 6 minutes

A large radio observatory dish beneath a dark night sky — Photo credit: Simon Delalande from Unsplash

Key Findings

A starshade would fly far from the telescope while staying precisely aligned.
Petal shape controls how diffracted light behaves at the telescope.
Formation sensing is as important as the shade material itself.

A starshade is simple in concept: put something between the telescope and the star. The difficulty is everything after that sentence.

Blocking without blurring

The shade must suppress starlight while allowing light from a faint nearby planet to reach the telescope. Its petal edges are shaped to control diffraction.

Flying a shadow

Because the shade and telescope would be separated by large distances, navigation becomes part of the optical system. The spacecraft must know whether the shadow is centered.