Abstract. Recent high-sensitivity imaging of the Sun's white-light corona from space has revealed a variety of unexpected small-scale phenomena, including plasma blobs that are ejected continually from the cusplike bases of streamers, fine raylike structures pervading the outer streamer belt, and inflows that occur mainly during times of high solar activity. These phenomena can be interpreted as different manifestations of magnetic field line reconnection, in which plasma and magnetic flux are exchanged between closed and open field regions of the corona. The observations provide new insights into a number of longstanding questions, including the origin of the streamer material in the outer corona, the sources of the slow solar wind, and the mechanisms that regulate the interplanetary magnetic field strength. The Streamer Belt as a Warped Plasma SheetAs has long been known from eclipse observations, the large-scale structure of the corona changes systematically over the l 1-year sunspot cycle. This effect is illustrated in Figure 1, which shows a pair of polarized-brightness images recorded with the LASCO C2 coronagraph in May 1997 and September 1999, respectively. In the earlier image, representative of the white-light corona near sunspot minimum, the streamers lie close to the heliographic equator, the higher latitudes being dominated by dark polar coronal holes traversed by faint polar plumes. In the later image, representative of the corona near sunspot maximum, the bright streamers are distributed more or less symmetrically about the solar disk, and the large polar holes are no longer present.The visual impression obtained from images like those in Figure 1 is that of a disjunct collection of cylindrical stalks.However, as we now demonstrate, the observed streamer structure beyond r • 2.5 Rs can be described by a model in which the scattering electrons are confined to a narrow, warped sheet located where the magnetic field reverses its polarity.We employ Sun-centered spherical coordinates (r, X, •b), with ;t denoting heliographic latitude and •b denoting Car-25,133