Lense–Thirring precessing magnetar engine drives a superluminous supernova | Nature

Subjects Astrophysical disks General relativity and gravity High-energy astrophysics Stars Abstract Type I superluminous supernovae (SLSNe-I) are at least an order of magnitude brighter than standard SNe, with the power source for their luminosity still unknown 1 , 2 , 3 . The central engines of SLSNe-I are suggested to be magnetars 4 , 5 but most of the SLSNe-I light curves have several bumps that are unexplained by the standard magnetar model 6 , 7 , 8 . Existing explanations for the bumps either modulate the engine luminosity or invoke interactions with circumstellar material (CSM). Surveys of the limited sample of SLSN-I light curves find no compelling evidence favouring either scenario 7 , 9 , leaving both the nature of the light-curve fluctuations and the applicability of the magnetar model unresolved. Here we report high-cadence multiband observations of a SLSN-I with clear ‘chirped’ (that is, decreasing period) light-curve bumps that can be directly linked to the properties of the magnetar central engine. Our observations are consistent with a magnetar centrally located within the expanding supernova ejecta, surrounded by an infalling accretion disk undergoing Lense–Thirring precession. Our analysis demonstrates that the light curve and bump frequency independently and self-consistently constrain the magnetar spin period to P = 4.2 ± 0.2 ms and the magnetic-field strength to B = (1.6 ± 0.1) × 10 14 G. These results provide the first observational evidence of the Lense–Thirring effect in the environment of a magnetar and confirm the magnetar spin-down model as an explanation for the extreme luminosity observed in SLSNe-I. We anticipate that this discovery will create avenues for testing general relativity in a new regime—the violent centres of young SNe. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution Access options Access through your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any time Learn more Subscribe to this journal Receive 51 print issues and online access $199.00 per year only $3.90 per issue Learn more Buy this article Purchase on SpringerLink Instant access to the full article PDF. USD 39.95 Prices may be subject to local taxes which are calculated during checkout Fig. 1: Multiband light curves of SN 2024afav. Fig. 2: Diagram of disk infall and precession. Fig. 3: Alternative explanations of modulations. Fig. 4: Application to legacy SLSNe-I. Data availability The photometric and spectroscopic datasets analysed during the present study are available in the WISeREP online database ( https://www.wiserep.org/object/27312 ). Code availability The code used to run parts of this analysis as well as sample walkers from MOSFiT are available on Github ( https://github.com/jrfarah/24afav_analysis ). References Gal-Yam, A. in Handbook of Supernovae (eds Alsabti, A. W. & Murdin, P.) 195–237 (Springer, 2017). Moriya, T. J., Sorokina, E. I. & Chevalier, R. A. Superluminous supernovae. In Supernovae (eds Bykov, A. et al.) Vol. 68, 109–145 (Springer, 2019). Quimby, R. Superluminous supernovae. Zenodo https://doi.org/10.5281/zenodo.3478147 (2019). Kasen, D. & Bildsten, L. Supernova light curves powered by young magnetars. Astrophys. J. 717 , 245–249 (2010). Article ADS Google Scholar Woosley, S. E. Bright supernovae from magnetar birth. Astrophys. J. Lett. 719 , L204–L207 (2010). Article ADS Google Scholar Lunnan, R. et al. Hydrogen-poor superluminous supernovae from the Pan-STARRS1 Medium Deep Survey. Astrophys. J. 852 , 81 (2018). Article ADS Google Scholar Hosseinzadeh, G. et al. Bumpy declining light curves are common in hydrogen-poor superluminous supernovae. Astrophys. J. 933 , 14 (2022). Article ADS Google Scholar Chen, Z. H. et al. The hydrogen-poor superluminous supernovae from the Zwicky Transient Facility Phase I survey. II. Light-curve modeling and characterization of undulations. Astrophys. J. 943 , 42 (2023). Article ADS Google Scholar Chatzopoulos, E. & Tuminello, R. A systematic study of superluminous supernova light-curve models using clustering. Astrophys. J. 874 , 68 (2019). Article ADS CAS Google Scholar Kumar, A. et al. GOTO Transient Discovery Report for 2024-12-27. Transient Name Server Discovery Report, No. 2024-5091 (2024). de Wet, S., Wichern, H., Leloudas, G. & Yaron, O. ePESSTO+ Transient Classification Report for 2025-01-24. Transient Name Server Classification Report, No. 2025-337 (2025). Dong, X.-F., Liu, L.-D., Gao, H. & Yang, S. Magnetar flare-driven bumpy declining light curves in hydrogen-poor superluminous supernovae. Astrophys. J. 951 , 61 (2023). Article ADS Google Scholar Zhang, B., Li, L., Dai, Z.-G. & Zhong, S.-Q. Hydrogen-poor superluminous supernovae with bumpy light curves powered by precessing magnetars. Astrophys. J. 985 , 172 (2025). Article ADS Google Scholar Og