Observation of Wobbling and Precessing Jet Signatures in Gamma-Ray Emission from Blazar PKS 1424-41

We report a clear observational evidence for jet precession and nutation manifested in the gamma-ray emissions of the blazar PKS 1424 - 41. An analysis of about 16 yr of Fermi-LAT observations reveals three distinct and superimposed quasi-periodic oscillations (QPOs), with characteristic timescales of about 5.26 yr, about 0.96 yr and about 1.3 yr. The longer timescale is detected with a local significance of about 4.1 sigma (99.9958% confidence) and a global significance of about 2.45 sigma (98.5714% confidence). The shorter timescales (about 0.96 yr and about 1.3 yr) both show local significances exceeding 3 sigma. To interpret the origin of these modulations, we examine two physically motivated scenarios: Lense-Thirring precession of a misaligned accretion disk and orbital-driven jet precession in a binary supermassive black hole (BSBH) system. We model the gamma-ray variability using a compound framework that incorporates jet precession together with intrinsic jet rotation (nutation), which successfully reproduces the observed year-like QPOs. Our results indicate that the long-term, persistent about 5.26 yr oscillation is most consistent with a BSBH origin, while the shorter year-like QPO modulation can be naturally attributed to rotation or wobbling of the jet axis. If PKS 1424 - 41 hosts a supermassive black hole binary, it represents a promising target for future space-borne gravitational-wave observatories such as the Laser Interferometer Space Antenna (LISA), providing an independent probe of supermassive black hole binaries.