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Lunar Reference Systems

月球参考系统

基本信息

批准号：
199890609
负责人：
Professor Dr.-Ing. Jürgen Kusche
金额：
--
依托单位：
Institut für Geodäsie und Geoinformationstechnik
依托单位国家：
德国
项目类别：
Research Units
财政年份：
2011
资助国家：
德国
起止时间：
2010-12-31 至 2018-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/199890609?language=en
关键词：
Lunar Reference Systems

项目摘要

The goal of this project is to realize Moon-related systems consistently tied to the ITRS/ICRS, a prerequisite for further lunar science and exploration. This project also paves the way for transferring established geodetic methods for mapping of extra-terrestrial bodies. In the first period, basic concepts have been developed: We have improved LLR analysis and modelling, e.g. by an added ground and reflector station, as well as taking tidal displacements of lunar reflectors into account. We re-analysed the LLR data set including all currently available LLR normal points. Through simulations, we showed the benefit of novel reflector types. We have demonstrated how photographs of landing sites can be combined with LRO images to generate highly accurate local maps stabilised by the LLR reflector coordinates. We have developed techniques for LRO orbit determination based on different types of tracking data. In the second funding phase, these methods shall be further extended, e.g. by using LOLA crossovers or novel data from D-VLBI. The major objectives are to refine realisations of the lunar reference system, consistently embedded into the ICRF. This will be achieved by taking different measures:1) Realise LLR modelling with mm-level of accuracy. Refinement of models affecting lunar motion and rotation, e.g. external and internal torques, will further improve the LLR retroreflectors¿ coordinates as point-wise realisations of the lunar reference system.2) Reconstruct precise LRO orbits from multiple data sets. An independent capability for combined determination of orbits and low-degree harmonics of lunar gravity shall be established, using radiometric as well as LRO one-way laser tracking and altimetric data.3) Integrating novel data from missions LRO and GRAIL. We will develop a capability in Germany, independent from NASA, for referencing LRO altimetry and imagery to the lunar system, and contributing to improved physical parameters of the Moon. At the end of project, we will be able to analyse data from other orbiter missions.4) Data combinations. Combinations of LROC images and LOLA altimetry will lay the basis for accurately mapping the Moon. LROC images are combined with images from former lunar missions and tied to the LLR reflector coordinates. In the polar regions, accurate DTMs from LOLA will be the basis for generating illumination maps, which will be valuable for future landing missions, to identify places with the longest possible daylight hours.5) New solutions of the lunar reference system. A concept for the combination of LLR with VLBI observations will be developed by analysing simulated and, if possible, real differential VLBI measurements between radio transmitters on the Moon and quasars. As a major result, the current realisation of the selenocentric system will be improved to achieve accurate and Moon-wide uniform coordinate knowledge and a high-resolution lunar map. This lunar frame will be firmly tied to the ICRF and ITRF.

该项目的目标是实现与ITRS/ICRS一致的月球相关系统，这是进一步月球科学和探索的先决条件。该项目还为将已确立的大地测量方法用于测绘地外天体铺平了道路。在第一个阶段，基本概念已经发展：我们改进了LLR分析和建模，例如通过增加地面和反射站，以及考虑月球反射器的潮汐位移。我们重新分析了LLR数据集，包括所有当前可用的LLR正态点。通过模拟，我们展示了新型反射器的好处。我们已经演示了如何将着陆点的照片与LRO图像结合起来，生成由LRO反射器坐标稳定的高精度局部地图。我们开发了根据不同类型的跟踪数据确定LRO轨道的技术。在第二个筹资阶段，将进一步扩展这些方法，例如使用LOLA交叉数据或D-VLBI的新数据。主要目标是完善月球参考系统的实现，始终嵌入ICRF。这将通过采取不同的措施来实现：1)实现mm级精度的LLR建模。对影响月球运动和旋转的模型的改进，例如外部和内部扭矩，将进一步改善LLR后向反射器的坐标，作为月球参考系统的逐点实现。2)从多个数据集重建精确的LRO轨道。利用辐射和LRO单向激光跟踪和测高数据，建立独立的轨道和月球重力低次谐波联合测定能力。3)整合LRO和GRAIL任务的新数据。我们将在德国开发一种独立于NASA的能力，用于参考LRO的测高数据和月球系统的图像，并为改善月球的物理参数做出贡献。在项目结束时，我们将能够分析来自其他轨道飞行器任务的数据。4)数据组合。LROC图像和LOLA测高数据的组合将为精确测绘月球奠定基础。LROC的图像与以前月球任务的图像结合在一起，并与LROC反射器的坐标联系在一起。在极地地区，来自LOLA的精确dtm将成为生成照明地图的基础，这将对未来的着陆任务很有价值，以确定白昼时间最长的地方。5)月球参照系的新解。将通过分析月球和类星体上的无线电发射机之间模拟的和（如果可能的话）真实的差分VLBI测量结果，提出将LLR与VLBI观测相结合的概念。其主要成果是，目前的月心系统实现将得到改进，以实现精确的、全月范围的统一坐标知识和高分辨率的月球地图。这个月球框架将与ICRF和ITRF紧密相连。