图 1：云南天文台丽江高美古观测站；Lijiang Observatory (IAU code: 044) of Yunnan Astronomical Observatories, Chinese Academy of Sciences (CAS).

经前期深入调研、实地勘察、专家论证、台址监测，梦飞巡天望远镜安装在云南天文台丽江天文观测站（见图 1），由云南天文台负责改造升级现有基础设施，以满足梦飞巡天望远镜项目要求。观测站坐落于中国西南，东经100°01′48′′，北纬26°41′42′′，海拔3200米。常年以高原气候和亚热带季风气候为主，空气洁净，透明度高，光污染低，大气消光率低。

After an in-depth investigation, on-the-spot survey, expert demonstration, and site monitoring, Mephisto is decided to be installed at Lijiang Gaomeigu Observatory (see Fig. 1), Yunnan Observatories (YNAO), Chinese Academic of Science (CAS). YNAO is responsible for the site development to meet the requirements of the Mephisto project. The Lijang Observatory is in southwest China, with longitude 100°01′48′′ East, latitude 26°41′42′′ North, and altitude of 3200 meters. The site is dominated by plateau climate and subtropical monsoon climate. The air is clean with high transparency, low light pollution, and low atmospheric extinction.

望远镜圆顶由南京天文仪器有限公司负责设计、制造和安装。梦飞巡天望远镜圆顶采用与丽江2.4米望远镜圆顶类似设计，外径13米，包含6个侧窗以及4个风道，可以很快降低圆顶内外温差，保障圆顶视宁度。

Nanjing Astronomical Instrument Co., Ltd., CAS is responsible for designing, constructing, and installing the Mephisto dome.  It adopts a similar design to that of the Lijiang 2.4-meter telescope, with 13 meters in diameter, 6 side windows, and 4 wind holes on the ground, which could make the temperature in the dome rapidly approach to the environment, maintaining the dome seeing to a  optimal level.

2019年1月建成梦飞巡天望远镜台址监测系统（见图 2），为梦飞巡天望远镜未来巡天提供了详实的台站数据基础。系统包括8要素气象站、ADIMM、云量计、全天相机、天空背景计。截至目前，监测结果显示：视宁度中值1.2′′，每年可观测小时~1800小时，风向以西南风、西风和南风为主，风速中值3.2 m/s，在晴朗的无月夜，天顶天光亮度暗至V~21.75等。

A new monitoring system  was installed in January 2019, providing valuable data for the future operation of Mephisto. The system includes an 8-aspects climatological station, ADIMM, nephometer, all-sky camera and sky-background meter.  Till now, the weather condition at the Mephisto location is summarized as follows: the median seeing 1.2′′, ~1800 observational hours per year. The wind is mainly from the south-west, west and south directions, with a median speed of 3.2 m/s.  The zenith sky brightness is as dark as V ~ 21.75 mag during the moonless and cloudless night.

图 2：位于12米高水塔上的梦飞巡天望远镜台址监测系统，左图为水塔，右图为水塔上的监测系统； The Mephisto site monitoring system is mounted on a tower at a height of 12m. A global view of the tower and the layout of the monitoring system on top of the tower are shown in the left and right panels, respectively.