The polar contribution to the heat flow of Io

Polar brightness temperatures on Io are higher than expected for any passive surface heated by absorbed sunlight. This discrepancy implies large scale volcanic activity from which we derive a new component of Ioʹs heat flow. We present a ‘Three Component’ thermal background, infrared emission model for Io that includes active polar regions. The widespread polar activity contributes an additional ∼0.6 W m−2 to Ioʹs heat flow budget above the ∼2.5 W m−2 from thermal anomalies. Our estimate for Ioʹs global average heat flow increases to ∼3±1 W m−2 and ∼1.3±0.4×1014 watts total.