The challenge of detecting an Earth-like planet is significant due to the fact that it is approximately 10 billion times fainter than its parent star. To capture the faint light reflected from the planet, a coronagraph must be used to block almost all of the star’s light. However, any instability in the telescope’s optics can lead to leakage of starlight and cause glare that masks the planet.
Precise control of both the telescope and the instrument’s optical quality, or wavefront, is necessary for detecting an Earth-like planet using a coronagraph. This requires an exceptional level of control to 10s of picometers (pm), which is roughly on the order of the size of a hydrogen atom. This underscores the extraordinary precision needed for this endeavor.