An unsolved problem facing scholars has been where and how solar wind plasma from the sun’s atmosphere penetrates into the terrestrial magnetosphere, which is our planet’s outermost shielding, during geomagnetically quiet times. Recently, by using multi-spacecraft data, an international scientific research team led by Prof. Shi Quanqi from the Institute Space Science (ISS) of Shandong University and Prof. Zong Qiugang from the School of Earth and Space Sciences of Peking University found an unexpected and significant Solar wind entry window in the high-latitude terrestrial magnetosphere. This result has recently been published by Nature Communications.

The Earth is one of the six planets in our solar system that has magnetic fields, which are block and deflect most solar wind charged particles from the sun’s atmosphere, and prevent them from directly interacting with the atmosphere of the planet. This shielding is thought to be one of the most important factors protecting life on the ground and protecting spacecraft in geospace from being damaged. A small portion of the solar wind charged particles penetrate into the terrestrial magnetosphere, the shielded region of geospace, and participate in active magnetospheric, ionospheric and upper atmospheric processes, such as storms, substorms, aurorae and other space weather effects which can be hazardous to satellites, communication networks, power facilities and navigation systems and can even threaten the safety astronaut. An understanding of the movement of solar wind plasma throughout the terrestrial magnetosphere is therefore one of the most important issues in space science and space weather. It is generally thought that the majority of these penetrating solar wind plasmas enter through the low latitude region during active times. But there is no consensus as to where and how the solar wind enters during quiet times. Using cluster multi-satellite data, the researchers report observations of several new and unexpected solar wind plasma entry regions discovered in the high latitudes of the Earth’s magnetosphere, that is, the lobes tailward of the cusp region, during quiet times. From several observational facts as well as data simulation, they suggest that these regions are most likely produced by magnetic reconnection at the high-latitude magnetopause. They also found that the occurrence of these regions suggests that they are responsible for the majority of the plasma entry into the terrestrial magnetosphere region during such quiet times.

This work is supported by Natural National Science Foundation of China (NNSFC) and the Shandong Natural Science Foundation. The Center for Space Weather (CSW) of Shandong University was founded in 2007, and is one of the newly-developed space physics branches in China. After its initial rapid development, CSW has grown into a dynamic and outstanding research group with ten faculties. The group members has garnered several prestigious awards including the Sunanda and Santimay BASU-early career award presented by the AGU-SPA division, the Youth Award in Science and Technology of Shandong Province, and the Fu Min Xing Lu Labor Award of Shandong Province. They are also awarded funding for more than ten research projects from the NNSFC. They have published more than 30 papers in top journals such as Astrophysical Journal, Journal of Geophysical Research, Astronomy and Astrophysics, Physical Review X, and Solar Physics, and have given more than 10 invited talks in international academic conferences as invited speakers. CSW has already been recognized by both the Chinese and international space physics community.

For further information, please visit:http://www.nature.com/ncomms/journal/v4/n2/full/ncomms2476.html

Source: SDU at Weihai,www.view.sdu.edu.cn