Discovery alert: Spock’s home planet goes “poof”

The bad news for Star Trek fans comes from an instrument called NEID, recently added to the Kitt Peak National Observatory telescope complex. NEID, like other radial velocity instruments, relies on the “Doppler” effect: shifts in a star’s light spectrum that reveal its wobbling motions. In this case, analysis of the supposed planetary signal at different wavelengths of light emitted from different levels of the star’s outer envelope, or photosphere, revealed significant differences between the individual wavelength measurements – their Doppler shifts – and the overall signal when they were all combined. That means the planetary signal is, in all likelihood, actually the flickering of something on the star’s surface, coinciding with a 42-day rotation – possibly the stirring up of hotter and cooler layers beneath the star’s surface, called convection, combined with surface features of the star such as spots and “plages,” or bright, active regions. Both of these can alter a star’s radial velocity signals.