Scientific and Technical Discovery at the Millstone Hill Geospace Facility

该奖项是对马萨诸塞州韦斯特福德的米尔斯通山天文台(MHO)的维护和运营的奖励。MHO位于麻省理工学院的干草堆天文台，该天文台已经由该研究所设立了几十年。该站点包括两个2.5兆瓦的超高频发射机，一个固定的天顶直径68米的天线和一个46米的全转向天线。1958年，美国麻省理工学院林肯实验室为美国空军建造了超高频雷达，用于弹道导弹和卫星跟踪。1974年，美国国家科学基金会开始支持高层大气的雷达作战研究。这两个非相干散射雷达的功率和频率在世界上仍然是独一无二的，有几个这样的雷达仍在为科学工作。现代技术还没有超过这种雷达和其他类似雷达所能达到的分辨率。除了为美国科学界维护这一独特的资产外，该奖项还为Madrigal数据库提供资金，该数据库是来自地球各地的地面观测的中央数据库。这是航空科学界的一项关键资产。MHO在中纬度、亚极光地带进行测量，使其成为国家稳定机构极光带资产(阿雷西博天文台和吉卡马卡射电天文台)之间的关键位置。2020-2025年MHGF计划将在地球空间科学的前沿开展电离层和热层研究。这些研究包括：(1)热层-电离层动力学和变异性研究，包括潮汐、行星波和电离层行进扰动的长持续时间雷达观测；(2)波和扰动特征研究，包括太阳终结器、中层重力波和整个大气的耦合反应；(3)地磁暴反应和磁层-电离层耦合；(4)2024年4月美国大陆日全食期间的日食反应和动力学。MHGF将使地球空间雷达观测能够支持社区科学目标，办法是：(1)增加米尔斯通山的总观测时间，将雷达观测时间从约1000小时/年增加到1250小时/年；(2)利用适合系统科学调查的大视场提供亚极光覆盖；以及(3)利用经过验证和校准的系统提供高质量数据。国土安全部将开展一系列新的为期30天的米尔斯通山IS雷达中纬度活动，这些活动将：(1)在雪松和GEM讲习班组织以科学为重点的规划工作；(2)协调更多的地面和天基观测，以最大限度地实现科学回报；(3)领导对上述专题以及Cedar和GEM所界定专题的数据分析；以及(4)组织和主办为期30天的模式-数据比较讲习班，以促进将IS雷达数据用于地球空间系统科学。MHGF将展示一种新的基于中纬度流星雷达的中性风观测能力，使用先进的无线电捕获和快速平台，将(1)测量米尔斯通山上空的精细中间层中性风结构；(2)重叠30天的IS雷达运行，并提供大约一年的中性风数据；(3)探索比较IS雷达和基于多进多出(MIMO)的流星风测量的技术。MHGF还将生产和提供基于GNSS的总电子含量数据产品，这些产品(1)提供视线和垂直总电子含量观测并进行偏差校准；(2)支持社区在地球空间科学研究中使用GNSS产品。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is for the maintenance and operations of the Millstone Hill Observatory (MHO) in Westford, Massachusetts. MHO sits at the MIT Haystack Observatory which has been by the institute for many decades. The site consists of two 2.5MW UHF transmitter, a fixed zenith 68m diameter antenna and a 46m fully steerable antenna. In 1958, the UHF radar was built by MIT Lincoln Laboratory for the US Air Force for ballistic missile and satellite tracking. In 1974, NSF began supporting the radar operations studies of the upper atmosphere. The power and frequency of these two incoherent scatter radars remain unique in the world, with a handful of such radars still in operation for science. Modern technology has yet to surpass the resolution that can be obtained by this radar and the others like it. In addition to maintaining this unique asset for the US scientific community, this award provides funding for the Madrigal database, which is a central database groundbased observations from across the planet. It is a key asset for the Aeronomical science community. MHO makes measurements in the mid latitudes, subauroral zone making it a key location between NSFs auroral zone assets (AMISR) and equatorial assets (Arecibo Observatory and Jicamarca Radio Observatory).The 2020-2025 MHGF program will conduct ionospheric and thermospheric research at the frontiers of Geospace science. These include (1) thermosphere-ionosphere dynamics and variability studies, including tides, planetary waves, and traveling ionospheric disturbances using long duration IS radar observations; (2) studies of wave and disturbance signatures including those from the solar terminator, mesospheric gravity waves, and coupled whole atmospheric responses; (3) geomagnetic storm response and magnetosphere-ionosphere coupling; and (4) eclipse response and dynamics during the April 2024 continental US total eclipse. MHGF will enable Geospace radar observations to support community science objectives, through (1) increasing total Millstone Hill IS radar observation time from ~1000 hours/year to 1250 hours/year; (2) providing sub-auroral coverage using a wide field of view suited for system science investigations; and (3) producing high quality data using validated and calibrated systems. MHGF will conduct a new series of annual 30-day continuous Millstone Hill IS radar mid-latitude campaigns that will (1) organize a science focused planning effort at the CEDAR and GEM workshops; (2) coordinate additional ground and space-based observations to maximize science returns; (3) lead data analysis for the topics listed above and those defined by CEDAR and GEM; and (4) organize and host a 30-day run focused model-data comparison workshop to promote IS radar data use for geospace system science. MHGF will demonstrate a new mid-latitude meteor radar based neutral wind observation capability using advanced radio capture with the RAPID platform that will (1) measure fine-scale mesospheric neutral wind structure over Millstone Hill; (2) overlap a 30-day IS radar run and provide approximately one year of neutral wind data; and (3) explore techniques for comparison of IS radar and multiple-in multiple-out (MIMO) based meteor wind measurements. MHGF will also produce and make available GNSS based total electron content data products that (1) provide line of sight and vertical total electron content observations with bias calibration; and (2) support the use of GNSS products in Geospace science research by the community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.