Detecting an Earth-like planet presents a significant challenge due to its dimness compared to its parent star. This makes it extremely difficult to collect the faint light reflected from the planet, as it is overshadowed by the brightness of the star. To effectively capture this light, it is necessary to block nearly all of the star’s light using specialized technology such as a coronagraph.
However, even with this technology, careful control of the telescope’s optics is still required to prevent any instability that could lead to leakage of starlight. Factors such as misalignment between mirrors or changes in mirror shape can result in glare that obscures the planet, making it even more challenging to detect. In order to successfully detect an Earth-like planet using a coronagraph, precise control of both the telescope and instrument’s optical quality must be achieved at an extraordinary level, on the order of 10s of picometers (pm), which is approximately the size of a hydrogen atom. This level of precision is critical in order to effectively capture the faint light emitted by an Earth-like planet.