The orchestra is playing loudly, and someone in the third row is whispering. Hearing that whisper is the task facing astronomers studying the star HR 8799: four bright giant planets drown out the faint light of a possible fifth, hidden very close to the star.

The James Webb Space Telescope used a mask with seven holes to turn its mirror into something like a diffraction grating. The light from the planets adds up into a pattern that reveals their positions. But detector noise was spoiling that pattern. The new Amigo pipeline built a complete model of how light travels from photons to pixels, accounted for these disturbances, and subtracted them. What remained was a peak 150 milliarcseconds north of the star. It is like spotting a coin from 200 kilometers away. The source's contrast came out to 2.2×10⁻⁴, only slightly above the 3σ threshold, but an orbital fit gives the candidate, f, a semimajor axis of about 7 astronomical units and a mass of 1.7 Jupiter masses.

Previously, the inner region of HR 8799 remained out of reach because of systematic detector errors that corrupted interference patterns at small angular separations. Now the method of fully forward-modeling the NIRISS detector opens up zones that were hidden before. It can be applied right away to archival JWST data to search for faint companions around other stars.

The orchestra keeps playing, but now we have a score that includes the whisper too. All that's left is to wait for follow-up observations to confirm that the fifth planet really does move together with the star, and isn't just a chance glint.