木星大气探测综述 木星大气探测综述
 大气科学  2018, Vol. 42 Issue (4): 890-901 PDF

Spacecraft Missions to Jupiter
Wei Qiang, Hu Yongyun
Laboratory for Climate and Atmosphere-Ocean Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871
Abstract: China is planning to launch the country's first spacecraft to Jupiter and its satellites around 2030. The space mission has organized a series of discussions for scientists and engineers. Proposals of scientific objectives and engineering techniques are being collected. To help formulate the scientific goals of the Jupiter mission, the authors review past missions to Jupiter conducted by the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA). Among the nine space missions that explored Jupiter and its satellites so far, seven are flyby missions. The two others particularly for Jupiter, Galileo and Juno, carried many suites of instruments. Observations are not limited to Jupiter's atmosphere. Rather, they extend to the magnetosphere, ionosphere, and internal structures. In this paper, the authors focus on observations of the Jovian atmosphere. The authors introduce the flyby missions briefly, while the Galileo and Juno spacecrafts are summarized in greater details. The authors also discuss some of the outstanding questions.
Key words: Jupiter      Jovian atmosphere      Planet      Deep space exploration      Atmospheric dynamics
1 引言

 图 1 木星结构示意图。修改自Wahl et al.（2017） Figure 1 Schematic plot of Jupiter's structure. Adapted from Wahl et al. (2017)

2 飞越观测

7次飞越观测的飞船均由美国宇航局发射，分别是先锋10号（Pioneer 10，Kliore et al., 1974)、先锋11号（Pioneer 11，Ingersoll et al., 1975)、旅行者1号（Voyager 1，Broadfoot et al., 1979; Smith et al., 1979b)、旅行者2号（Voyager 2，Smith et al., 1979a）、尤利西斯（Ulysses，Smith et al., 1992）、卡西尼（Cassini，Brown et al., 2003; Porco et al., 2003）和新视野号（New Horizons，Reuter et al., 2007; Stern, 2008）。表 1给出了7次飞越观测飞船的名称、距离木星最近位置的时间以及最近距离。

2.1 先锋号飞船

2.2 旅行者号飞船

2.3 卡西尼、尤利西斯和新视野号飞船

 图 2 卡西尼号飞船于2000年12月7日拍摄的木星照片，照片分辨率是每像素144 km。照片中的黑点是木星的卫星欧罗巴（Europa）投射到木星上的影子。照片来自NASA/JPL/University of Arizona Figure 2 A photo of Jupiter taken by Cassini spacecraft on 7 December 2000 at a resolution of 144 km per pixel. The black dot is the shadow of Jupiter's satellite, Europa. Image from NASA/JPL/University of Arizona

 图 3 纬向风随纬度的分布，虚线是旅行者号在1979年观测的纬向风速（Limaye, 1986），实线是卡西尼号在2000年观测的纬向风速（Porco et al., 2003）。引自Ingersoll et al. (2004) Figure 3 Zonal wind as a function of latitude, the dashed line is measured by Voyager in 1979 (Limaye, 1986), the solid line is measured by Cassini in 2000 (Porco et al., 2003). Cited from Ingersoll et al. (2004)

 图 4 旅行者号测量的木星大气对流层和平流层温度垂直廓线。引自Lindal et al. (1981) Figure 4 Vertical temperature profiles in the upper troposphere and stratosphere, measured by Voyager 1. Cited from Lindal et al. (1981)

3 专门探测

3.1 伽利略号

 图 5 伽利略探测器测量的纬向风风速随大气层高度的变化。中间实线为测得的风速，左右两条为误差上界和下界。引自Atkinson et al. (1998) Figure 5 Zonal wind as a function of altitude, measured by the Galileo probe. The upper and lower values envelop the best-fit data (central line). Cited from Atkinson et al. (1998)
3.2 朱诺号

 图 6 朱诺号携带的相机于2017年5月25日拍摄的木星南极大气运动状况。照片拍摄时，朱诺号飞船距离木星云顶约5200 km。照片来自NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles Figure 6 Atmospheric movement of Jupiter's south pole taken by Juno camera on 25 May 2017. Juno was about 5200 km away from the Jupiter's cloud top as the image was taken. Image from NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

 图 7 6个微波通道测量的最低亮温随纬度的分布，黑色和绿色线是分别于2016年8月27日和12月11日测量的。左侧垂直坐标表示最低亮温（单位：K），右侧垂直坐标表示氨云顶以下的大气层深度，6个微波通道对应的气压值也在图中给出。背景图是哈勃太空望远镜于2016年2月10日拍摄的木星可见光照片的一部分（PIA19643）。引自Bolton et al. (2017) Figure 7 Nadir brightness temperatures in the six channels of the microwave versus latitude. The black and green curves are from the Perijove passes on 27 August 2016 and 11 December 2016. The left vertical axis shows nadir brightness temperature (units: K), the right vertical axis shows depth below the top of ammonia clouds, pressures corresponding to the six channels of microwave sounding are also marked on the plot. The background is an image of a Jupiter map taken by the Hubble Space Telescope on 10 February 2016 in the visible wavelength range (PIA19643). Cited from Bolton et al. (2017)

 图 8 纬向平均氨气体积混合比垂直剖面。引自Bolton et al. (2017) Figure 8 Vertical cross section of zonal mean ammonia mixing ratio. Cited from Bolton et al. (2017)

4 结论和讨论