Endogenic heat at Enceladus' north pole.
Where this comes from
- Record sourced from PubMed, PMID 41202129.
- Also identified by DOI 10.1126/sciadv.adx4338 and PMC identifier 12594170.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The long-term survival of Enceladus' ocean depends on the balance between heat production and heat loss. To date, the only place where a direct measurement of Enceladus's heat loss has been made is at the south pole. Here, we show that the north pole also emits heat at a greater rate than can be explained by purely passive models. By comparing winter and summer observations taken with the Cassini Composite InfraRed Spectrometer, we find a winter temperature ~7 kelvin warmer than passive modeling predicts, accounting for uncertainties in emissivity and thermal inertia. An additional endogenic heat flux of 46 ± 4 milliwatts per square meter is required to match the observed radiance. The implied local shell thickness is 20 to 23 kilometers-consistent with the higher end of thickness models based on gravity, topography, and libration measurements. This work provides a previously unidentified constraint for models of tidal heat production, shell thickness, and the long-term evolution of Enceladus' ocean.