南方基地知识库

台址信息监测系统是现代天文观测台站必备的辅助系统之一,在开展天文实测过程中发挥着重要的作用。首先介绍了丽江天文观测站的基本概况,目前己经投入运行的天文望远镜设备,以及丽江2.4 m通用光学望远镜上配备的科学终端仪器。随后论述了国内外优秀天文观测台站己配备的台址信息监测设备,重点阐述了丽江天文观测站建立的台址信息监测系统。分析了丽江站一个年度的气象数据、云量数据、可观测小时数、可观测夜数和天光背景数据,以及近几年测量的大气视宁度数据,得出丽江站全年的光学天文观测条件的基本特征。根据实际观测情况,将丽江2.4 m望远镜全年的观测时间段分为三个等级,为国内天文学家申请使用并开展科学观测提供参考。 

Lijiang Observatory (also known as GMG) is at 100°01′48″(E), 26°41′42″(N), 3200m above sea level, 40km from Lijiang City. There are 8 telescopes: Lijiang 2.4-m Telescope (LJT), lijiang 1.8-m telescope, Sino-Thai 70-cm telescope (STT), Burst Optical Observer and Transient Exploring System 4 (BOOTES4), Yunnan-Hong Kong 45-cm Transiting Exoplanet Survey Telescope (TEST), 30-cm Automated DIMM, 9-cm Taiwan Automatic Telescope network 3 (TAT) and 10-cm Lijiang Coronagraph Telescope (LCT). Lijiang 2.4-m Telescope is a general-use optical telescope, which has 6 scientific instruments, defferent instruments can be changed in one minute by using the rapid instrument exchanging system. The instruments including: YFOSC (Yunnan Faint Object Spectrograph and Camera), PICCD (Princeton Instruments VersArray 1300B CCD Camera), LiJET (LiJiang Exoplant Tracker), CHILI (China Lijiang Integrated Field Unit), HiRES (fiber-fed High-Resolution Echelle Spectrograph), EMCCD, et al. The Astronomical Site Monitoring System (ASMS) of Lijiang Observatory is composed of astro-climatic station (ACS) and astro-monitoring station (AMS). The ACS includes meterological station, cloud sensor, brightness sensor and seeing monitor DIMM; the AMS includes the all-sky camera and video sureillance. Data acquisition frequency of the ASMS of Lijiang Observatory is 1 min for a set of data, we analysed a full year's data, summing up the basic observation condition of Lijiang Observatory. The average temperature is 8℃, the average relative humidity is 71%, the average wind speed is 1.36m/s, more than 80% of the wind direction is southwest. The cloud amount is 3.2 in observing session, but 8.2 in non-observing session. The total observation time is about 2150h, equal to 210~220 nights (if the observation time is longer than 3h, it will be defined as an observation night). The average seeing is about 1.2", in conclusion, Lijiang Observatory is one of the best optical astronomical sites in China, it has good seeing condition and low wind speed, very transparent atmosphere and nearly no light pollution. The best observation session is from October to next May.