资源环境科技发展态势分析平台

We use an infrared data set captured between 1984 and 2017 using several instruments and observatories to report five rare equatorial disturbances that completely altered the appearance of Jupiter's equatorial zone (EZ): the clearance of tropospheric clouds revealed a new 5- mu m-bright band encircling the planet at the equator, accompanied by large 5-mu m-bright filaments. Three events were observed in ground-based images in 1973, 1979, and 1992. We report and characterize for the first time the entire evolution of two new episodes of this unusual EZ state that presented their maximum 5-mu m-brightness in December 1999 and February 2007, coinciding with a brown coloration south of the equator and with large bluish filaments and white plumes in the northern EZ at visible wavelengths. We characterize their typical infrared-bright lifetimes of 12-18 months, with possible periodicities of 6-8 or 13-14 years. We predict that a full-scale equatorial disturbance could occur in 2019-2021.

Plain Language Summary Jupiter's banded structure, white zones (cloud-covered regions) and brown belts (cloud-free regions), exhibits dramatic planetary-scale changes. In this paper, we report five rare events at Jupiter's equatorial zone that changed the appearance of this zone completely at the cloud forming region (1-4 bar), leaving a bright band at the equator, accompanied by narrow and bright filaments (festoons) at the northern equatorial zone. We use ground-based 5-mu m data, which reveal the thermal emission from 1 to 4 bar region (bellow the ammonia cloud), captured between June 1984 and August 2017 (almost three Jovian years) to report and characterize for the first time two new disturbances at Jupiter's equatorial zone that took place in 1999-2000 and 2006-2007. We found that changes in the cloud morphology at the equatorial zone during these disturbances occurred first at the cloud tops (similar to 700 mbar), months before they were observed at the cloud forming region at 1-4 bar. We also found that these disturbances are confined at the cloud deck (similar to 150 mbar to 4 bar), lasting 12-18 months. After analyzing five documented equatorial zone disturbances, we conclude that these events are periodic/stochastic with typical intervals of 6-8 or 13-14 years. We predict a new disturbance in 2019-2021, during Juno's exploration epoch.