Collaborative Research: A Multi-Frequency Campaign to Probe Neptune's Dynamics and Deep Atmospheric Structure

根据地面和太空望远镜的观测结果，海王星大气层的循环已经建立了模型。科学家们现在认为，海王星有一个大气层，其中的气体在海王星的赤道和南极下沉，在中纬度上升。但科学家们也看到了云，那里的空气预计会下沉，而稀薄的大气，那里的空气预计会上升。为了研究这一矛盾，研究人员将使用射电望远镜和光学望远镜同时观测海王星。他们的目标是了解云的形成和气体的运动，以便了解海王星不同深度的大气组成，整个行星的大气循环，风暴，以及海王星所有地方不寻常的局部变化。学生和业余天文学家也将参与这个项目。这项研究通过详细介绍海王星的结构和组成，为国家利益服务。海王星是太阳系四颗气态巨行星之一，与其他恒星周围发现的许多行星相似。研究人员还定期向公众介绍他们的研究，并将介绍海王星的故事，以及它与行星形成的一般关系。一个海王星的全球环流模型已经被推导出来，气体在中纬度上升，在赤道和南极下降。这种环流模式从平流层（0.1毫巴压力水平）一直延伸到对流层深处的几十毫巴。然而，仍有许多谜题存在，例如在空气下沉的区域（例如，南极、赤道）存在云，以及在中南部纬度相对较低的射电不透明度，与空气上升的预期相反。主要研究人员将使用甚大阵列（1-13厘米）、阿塔卡马大型毫米/亚毫米阵列（1-3毫米）、哈勃太空望远镜（可见）和W. M.凯克天文台（NIR）望远镜的组合，经常同时观测海王星，将云的形成与气体动力学和冷凝结合起来。这些数据对于了解深层大气的组成、全球环流模式、局部风暴系统和海王星大气中的湍流运动至关重要。合并后的数据集覆盖了海王星从平流层到~100巴的整个高度范围。这颗行星的地图将以不同的频率制作，使用升级后的VLA在纬度和经度上都能分辨出来。同时获得的可见光（HST）和近红外（Keck上的自适应光学）图像将描绘云和风暴的特征。将获得连续波长和几种不平衡物质（如CO、HCN、PH3）光谱窗内的ALMA数据。学生和业余天文团体将为这项研究做出贡献。研究人员还定期向公众介绍他们的研究，并将介绍海王星的故事，以及它与行星形成的一般关系。

The circulation of the planet Neptune's atmosphere has been modeled based on observations made from ground and space-based telescopes. Scientists now see Neptune as having an atmosphere with gases that sink at Neptune's equator and south pole, and rise at its mid-latitudes. But scientists have also seen clouds where air was expected to be sinking, and thinner atmosphere where air was expected to be rising. To study this contradiction, the investigators will use radio and optical telescopes to observe Neptune at the same time. They aim to understand the cloud formation and motions of gases, in order to understand the composition of Neptune's atmosphere at many different depths, the circulation of the atmosphere across the whole planet, storms, and unusual but local changes across all of Neptune. Students and amateur astronomers will also work on this project. This research serves the national interest by detailing the structure and composition of Neptune, one of four gas giant planets in the Solar System, and similar to many planets discovered around other stars. The investigators also regularly give talks to the public about their research, and will present the story of Neptune and how it relates to planet formation in general. A global circulation model of the planet Neptune has been derived, with gas rising at mid-latitudes and descending over the equator and the south pole. This circulation model extends from the stratosphere (0.1 mbar pressure levels) down to tens of bars into the deep troposphere. Many puzzles remain, however, such as the presence of clouds in regions of subsiding air (e.g., South pole, equator), and a relatively low radio opacity at mid-southern latitudes contrary to expectations of rising air. The principal investigators will use the combination of Very Large Array (1-13 cm), Atacama Large Millimeter/submillimeter Array (1-3 mm), Hubble Space Telescope (visible) and W. M. Keck Observatory (NIR) telescopes to observe Neptune often simultaneously to couple cloud formation to gas dynamics and condensation. These data are critical for understanding the composition of the deep atmosphere, the global circulation pattern, localized storm systems and turbulent motions in Neptune's atmosphere. The combined datasets cover Neptune's entire altitude range from the stratosphere down to ~100 bar. Maps of the planet will be produced at different frequencies resolved in both latitude and longitude using the upgraded VLA. Simultaneously-obtained images in the visible (HST) and NIR (adaptive optics on Keck) will characterize clouds and storms. ALMA data at continuum wavelengths and in the spectral windows of several disequilibrium species (e.g., CO, HCN, PH3) will be obtained. Students and the amateur astronomy community will contribute to this research. The investigators also regularly give talks to the public about their research, and will present the story of Neptune and how it relates to planet formation in general.