The Kitt Peak National Observatory’s NEID instrument has delivered some disappointing news to Star Trek fans. While NEID, like other radial velocity instruments, relies on the Doppler effect to detect wobbling motions of stars, a recent analysis of the supposed planet signal at different wavelengths of light emitted from various levels of the star’s photosphere revealed significant differences in Doppler shifts among individual wavelength measurements compared to the total signal when combined.
This discovery suggests that the planet signal detected by NEID is likely just a fluctuation in something on the star’s surface that corresponds to a 42-day rotation. This phenomenon could be caused by movement of hotter and cooler layers beneath the star’s surface, known as convection, along with spots and bright active regions called “plages” on the star. These features can affect a star’s radial velocity signals, leading to false detections of planets.
The NEID instrument’s observations were not due to the presence of a planet orbiting the star but rather from activity on its surface. This revelation underscores the complexities involved in interpreting data from radial velocity instruments and highlights the importance of considering all possible factors that could influence star signals.
