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Abstract: On July 22, 2011 and in the active region NOAA 11259 there ap- peared the event of the ejection of solar atmospheric Hα surges. According to the full-disc Hα observations of the Big Bear Solar Observatory in United States, three consecutive surges at one and the same place in the north of the main spot of the active region were discovered. The trajectories of these three surges exhib- ited the figure of straight lines, and their integral configuration is like an inverted Eiffel Tower. The first two surges are quite similar, and in each of them there appeared two bright points in the northern part of the main spot. After several minutes, the surges appeared in the midst of bright points. When the bright- ness of the bright points attained the maximum value, the surges spouted out from the midst of bright points. And after reaching the maximum altitude, they quickly vanished. Before the ejection of the third surge took place, no bright points appeared. Besides, its maximal altitude is merely one half of that of the first two surges. Via a comparison with the SDO/HMI (Solar Dynamics Obser- vatory/Helioseismic and Magnetic Imager) data of radial magnetic fields, it is found that in more than one hour before the appearance of the first surge there emerged bipolar magnetic fields in the region of ejection. Besides, in several min- utes before the ejection of each Hα surge the magnetic fluxes of positive polarity diminished. Via our analysis it is found that there appeared reconnections be- tween the newly emerging satellite magnetic fields and the preexisting magnetic fields in the spot, and this caused the continuous ejections of Hα surges. [Copyright &y& Elsevier]

Seven mediated and small ejective events on the sun observed at Ganyu Observing Station of Purple Mountain Observatory in 2000 are investigated. It is found that they were not accompanied by brightening. Their lengths were in the range 1–2.5×104 km, their widths, 3–5×103 km, and their lifetimes, 3–7 minutes. They were produced at places of weak magnetic fields and far away from large sunspots. These ejections are interpreted by numerical simulation with 1-D hydrodynamic equations of flow along magnetic arcs. As demonstrated by the results, they are different from the spicules and surges simulated by Suematsu et al. and Shibata et al. They are not matter with photospheric or chromospheric densities pushed by shock waves or rebound shock waves toward the solar corona, rather, they are ejections formed by continuous matter flows after magnetic reconnection. After evolving for about 5 minutes, they can attain a stationary hydrodynamic state. [Copyright &y& Elsevier]

On June 18, 2000, a small ejection phenomenon at the western limb of the sun was observed by Ganyu Station of Purple Mountain Observatory. Its lifetime was merely 15 minutes, and it did not belong to the ejection phenomena in late stages of solar flares. A very fine helical structure was visible. Assuming a velocity of 100 km/s produced by magnetic reconnection in the lower atmosphere and ignoring the Lorentz force, the height attainable by a column of ejecta of quasi-uniform density is derived, and the result is consistent with the observations. [Copyright &y& Elsevier]

This paper is to introduce a proposed deep space mission, which aims to perform in situ detection of the central structure, namely the magnetic reconnection current sheet, which drives the large-scale eruption on a star. The main focus of this mission is on the fine physical characteristics of the large-scale magnetic reconnection taking place on the Sun, our nearest star, revealing the secret of the most violent energy release process, also known as the solar storm, in the solar system. The scientific goal of this mission, magnetic reconnection, is a kernel process of energy conversion occurring in the magnetized plasma in the universe, and has long been a fairly important research topic or even research area in solar physics, space science, plasma physics, and the related fields. The in situ detection with a 5 ∼ 20 times enhanced spatial resolution of the instruments used on the Earth will provide us with the extra-clear images of the Sun and the related information. We are thus able to study, to learn, and to understand the Sun on an unprecedented platform, and further resolve the longstanding puzzle in the solar community regarding the fine physical property of the kernel process driving the solar eruption, as well as that of the coronal heating. [ABSTRACT FROM AUTHOR]