The solar corona is the most conspicuous part of the solar atmosphere in which flares and coronal mass ejections occur frequently and from which solar wind is flowing quasi-steadily. The corona is visible to our eyes only during total eclipses. In the past decade, a number of solar spacecraft, including SOHO, TRACE, RHESSI, Hinode, and STEREO, were launched to observe the corona in white-light, EUV and X-rays, which brought out many important observations and theories. A number of ground instruments have also been developed in recent years. Although our knowledge on the physics of the corona has been greatly advanced, many key problems remain unanswered, and in general, the corona is generally still mysterious to us.

The dynamics of the corona is controlled by the evolving photospheric magnetic field and guided by the coronal magnetic field. The measurement of both photospheric and coronal magnetic fields is extremely important. Recently, global vector magnetographs and high-resolution local magnetograms have been made available, which may shed light on the understanding of the coronal structures and dynamics. Recent observations show that the solar corona consists of many thin loops or threads with the plasmas brightening and fading independently. Efforts have been made to identify these loops through various observations. The dynamics in each thread is believed to be related to the formation of filaments. The filament threads are now found to be in a dynamic non-equilibrium or dynamic state, in contrast to what was previously thought. The mechanism sustaining the dynamics is worth exploring in detail. Coronal loops often show oscillations and waves, which provides a new window to diagnose the unknown coronal magnetic field, in particular the detection of Alfvenic waves with high-cadence observations during eclipses.

Solar flares and coronal mass ejections are the two most energetic phenomena on the Sun. Some advances have been made through radiative hydrodynamics, magnetic field extrapolations, MHD and kinetic simulations, etc. The SOHO spacecraft revealed a new phenomenon called "EIT waves", but the low cadence captures this mechanism insufficiently. High-cadence observations from STEREO and during eclipses in white light and in the red and green coronal lines are likely to reveal new wave phenomena. All these topics have a great impact on solar-terrestrial physics.

After more than two years of observations, the new spacecraft, Hinode and STEREO, have obtained many exciting results about the solar corona, especially the 3-dimensional view of coronal structures. These results will be discussed at the CAS-IAU joint meeting, and should be highly stimulating for researchers in solar physics.

The 2009 July 22 total solare eclipse, with a maximum duration of more than 6 minutes (some locations in China will see a duration of nearly 6 minutes) , is the longest one over a century. This unique chance will certainly attract a lot of solar physicists and astronomers from all over the world, , and so a topical meeting on solar physics near the best observational sites is very appropriate. The 3-day meeting offers an opportunity for solar physicists to exchange new results, discuss hot topics, and propose future observations and research. This meeting has also an educational impact on the society for its relation with the rare solar eclipse phenomenon, especially since China has the longest history of solar eclipse observations. Moreover, the year 2009 has been named as the International Year of Astronomy. This meeting just after the total solar eclipse is thus an important part of the activities associated with the global celebration of astronomy and its contributions to society and culture. The meeting is supported partly by IAU and partly by other organizations in China.

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