Radiant energies of planets and moons are of wide interest in the fields of geoscience and planetary science. Based on long-term multiinstrument observations from the Cassini spacecraft, we provide here the first observational study of Titan's global radiant energy budget and its seasonal variations. Our results show that Titan's radiant energy budget is not balanced over the Cassini era (2004–2017) with the absorbed solar energy (1.208 ± 0.008) × 10²³ J larger than the emitted thermal energy (1.174 ± 0.005) × 10²³ J. The energy imbalance is 2.9 ± 0.8% of the emitted thermal energy. Titan's global radiant energy budget is not balanced either at the timescales of Earth's years and Titan's seasons. In particular, the energy imbalance can be beyond 10% of the emitted thermal energy at the timescale of an Earth year. The energy imbalance revealed in this study has important impacts on Titan, which should be examined further by theories and models.

中文翻译：

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卡西尼号时代（2004-2017）泰坦的全球辐射能量收支

行星和卫星的辐射能在地球科学和行星科学领域受到广泛关注。基于卡西尼号航天器的长期多仪器观测，我们在此提供了对泰坦全球辐射能量收支及其季节性变化的首次观测研究。我们的研究结果表明，在卡西尼时代（2004-2017）期间，泰坦的辐射能量收支不平衡，吸收的太阳能（1.208±0.008）×10 ²³  J大于发射的热能（1.174±0.005）×10 ²³ J. 能量不平衡为散发热能的 2.9 ± 0.8%。泰坦的全球辐射能量收支在地球年和泰坦季节的时间尺度上都不平衡。特别是，在地球年的时间尺度上，能量不平衡可能超过排放热能的 10%。本研究揭示的能量不平衡对泰坦有重要影响，应通过理论和模型进一步研究。