SCIENCE CHINA Physics, Mechanics & Astronomy © Science China Press and Springer-Verlag Berlin Heidelberg 2011 phys.scichina.com www.springerlink.com *Corresponding author (email: shuhongyang@nao.cas.cn)  Research Paper  October 2011 Vol.54 No.10: 1906–1910 doi: 10.1007/s11433-011-4471-1 Polar plumes observed at the total solar eclipse in 2009 YANG ShuHong 1,2* , ZHANG Jun 1 , ZHANG ZhiYong 1 , ZHAO ZhaoWang 1 , LIU YangBing 1 , SONG Qian 1 , YANG ShangBin 1 , BAO XingMing 1 , LI LePing 1 , CHU Zhe 1 & LI Ting 1,2 1 Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China; 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China Received January 24, 2011; accepted April 15, 2011; published online August 30, 2011 During the total solar eclipse of July 22, 2009, we carried out a white-light observation in Anji, Zhejiang, China. The aim was to observe the polar plumes (PPs) with high spatial and temporal resolutions in white-light. With the observational data, we investigate the properties and evolution of the PPs and compare them with those of the low-latitude plumes (LPs). We find that both the PPs and the LPs have comparable lengths and widths, and the mean length and width are 300 Mm and 16 Mm, re- spectively. The average inclination angle (13 degree) of the PPs is smaller than that (32 degree) of the LPs. Generally, the plumes which are closer to the coronal hole center are more vertical. We trace the PPs and the LPs in the sequence of images and find that none of them disappears and no new one is created. Additionally, neither plasma outflow nor transverse oscilla- tion is observed. These imply that the evolution process of plumes is much longer than the timescale of eclipse. Sun: eclipses, Sun: corona, Sun: evolution PACS: 96.60.-j, 96.60.Tf, 92.60.Vb 1 Introduction Polar plumes (PPs) are bright raylike features located over the north and south polar coronal holes. They are deemed to trace out the open magnetic field lines. The formation of PPs is interpreted as small-scale magnetic reconnection at the coronal base [1,2]. The plasma in plumes is much denser than the interplume corona [3,4], and both plumes and in- terplume areas are suggested as sources of solar wind [5,6]. Solar eclipses as interesting astronomical phenomena at- tract astronomers and the general public all the time [7–9]. Observations at total solar eclipses have their advantages for scientific studies though lots of space-borne observatories are working [10,11]. At the total solar eclipse on August 1, 2008, several groups organized by the Chinese Academy of Sciences carried out scientific observations in Jiuquan, Gansu Province, and obtained many observational results [12–17]. Those results are related to many subjects of solar physics, such as the spectra and polarizations of the solar chromosphere and corona, and the fine structures of corona. More details can be found in a review of Zhang et al. [18]. When total solar eclipses occur, we have the opportunity to observe PPs in white-light on the ground. PPs have been investigated with solar eclipse observations, as well as ob- servations from the Solar and Heliospheric Observatory (SOHO [19]), the Solar Terrestrial Relations Observatory (STEREO [20,21]), and some other instruments [22–31]. However, what are the properties of PPs like in fine scale if observed with a high spatial resolution in white-light? How do the PPs evolve in short timescale if investigated with a high temporal resolution? The total eclipse which occurred on July 22, 2009 lasted about 6 min on mainland China. At that eclipse, we carried out a white-light observation in Anji, Zhejiang Province. The aim of our observation was to in- vestigate the properties and evolution of the PPs with high spatial and temporal resolutions in white-light.