探测土卫八两面的地下
Probing the subsurface of the two faces of Iapetus
摘要：
土星的卫星土卫八，这是在同步旋转，是由一个光学黑暗的材料覆盖主要是在其领先的一面，而其落后的一面是显着明亮。由于较长的波长探测更深的地下，观察双方在各种波长带来光的热，成分和物理性质随深度的可能变化。我们已经观察到Iapetus的领先和落后的半球在1.2和2.0毫米，使用NIKA2相机安装在IRAM 30米望远镜，并比较我们的意见，其他人在毫米至厘米波长。我们校准我们的观察土卫六，这是同时观察的视野内。由于靠近土星，有时很难将土卫八和土卫六的通量与土星的通量分开，在望远镜的旁瓣中检测到。初步结果显示，两个波长的后半球亮度温度在误差条内相等，与Ries（2012）的预测不同。在领先的一面，我们报告了一个陡峭的光谱斜率增加亮度温度（10 K）从1.2到2.0毫米，这可能表明快速变化的发射率在顶部几厘米的表面。比较漫散射模型和热模型将是必要的，以进一步限制的热物理性质的亚表面的土卫八的两个面孔。
英文摘要：
Saturn's moon Iapetus, which is in synchronous rotation, is covered by an optically dark material mainly on its leading side, while its trailing side is significantly brighter. Because longer wavelengths probe deeper into the subsurface, observing both sides at a variety of wavelengths brings to light possible changes in thermal, compositional, and physical properties with depth. We have observed Iapetus's leading and trailing hemispheres at 1.2 and 2.0 mm, using the NIKA2 camera mounted on the IRAM 30-m telescope, and compared our observations to others performed at mm to cm wavelengths. We calibrate our observations on Titan, which is simultaneously observed within the field of view. Due to the proximity of Saturn, it is sometimes difficult to separate Iapetus's and Titan's flux from that of Saturn, detected in the telescope's side lobes. Preliminary results show that the trailing hemisphere brightness temperatures at the two wavelengths are equal within error bars, unlike the prediction made by Ries (2012). On the leading side, we report a steep spectral slope of increasing brightness temperature (by 10 K) from 1.2 to 2.0 mm, which may indicate rapidly varying emissivities within the top few centimeters of the surface. Comparison to a diffuse scattering model and a thermal model will be necessary to further constrain the thermophysical properties of the subsurface of Iapetus's two faces.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
