A three-dimensional four species multi-fluid magnetohydrodynamic (MHD) model was constructed to simulate the solar wind global interaction with Mars. The model was augmented to consider production and loss of the sign...A three-dimensional four species multi-fluid magnetohydrodynamic (MHD) model was constructed to simulate the solar wind global interaction with Mars. The model was augmented to consider production and loss of the significant ion species in the Martian ionosphere, i.e., H^+, O2^+, O^+, CO^+2, associated with chemical reactions among all species. An ideal dipole-like local crustal field model was used to simplify the empirically measured Martian crustal field. Results of this simulation suggest that the magnetic pile-up region (MPR) and the velocity profile in the meridian plane are asymmetric, which is due to the nature of the multi-fluid model to decouple individual ion velocity resulting in occurrence of plume flow in the northern Martian magnetotail. In the presence of dipole magnetic field model, boundary layers, such as bow shock (BS) and magnetic pile-up boundary (MPB), become protuberant. Moreover, the crustal field has an inhibiting effect on the flux of ions escaping from Mars, an effect that occurs primarily in the region between the terminator (SZA 90°) and the Sun Mars line of the magnetotail (SZA 180°), partially around the terminator region. In contrast, near the tailward central line the crustal field has no significant impact on the escaping flux.展开更多
The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,Phobos.The physical nature of these"Phobos e...The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,Phobos.The physical nature of these"Phobos events"is examined using results from related investigations over the last twenty years.It is concluded that there is no clear evidence at present to support the association of magnetic field disturbances in the solar wind with Phobos.The situation will be further clarified taking advantage of the multi-spacecraft observations of the Yinghuo-1(YH-1),Mars Express and MAVEN missions beginning in 2012.It is expected that many novel features of solar wind interaction with Phobos(and possibly also Deimos) itself will also be revealed.展开更多
基金supported by the pre-research projects on Civil Aerospace Technologies No.D020103 and D020105 funded by China’s National Space Administration (CNSA)support from the National Natural Science Foundation of China (NSFC) under grants 41674176, 41525015, 41774186, 41574156, and 41941001
文摘A three-dimensional four species multi-fluid magnetohydrodynamic (MHD) model was constructed to simulate the solar wind global interaction with Mars. The model was augmented to consider production and loss of the significant ion species in the Martian ionosphere, i.e., H^+, O2^+, O^+, CO^+2, associated with chemical reactions among all species. An ideal dipole-like local crustal field model was used to simplify the empirically measured Martian crustal field. Results of this simulation suggest that the magnetic pile-up region (MPR) and the velocity profile in the meridian plane are asymmetric, which is due to the nature of the multi-fluid model to decouple individual ion velocity resulting in occurrence of plume flow in the northern Martian magnetotail. In the presence of dipole magnetic field model, boundary layers, such as bow shock (BS) and magnetic pile-up boundary (MPB), become protuberant. Moreover, the crustal field has an inhibiting effect on the flux of ions escaping from Mars, an effect that occurs primarily in the region between the terminator (SZA 90°) and the Sun Mars line of the magnetotail (SZA 180°), partially around the terminator region. In contrast, near the tailward central line the crustal field has no significant impact on the escaping flux.
基金supported in part by NSC Grant NSC 96-2752-M-008-011-PAE and Ministry of Education under the Aim for Top University Program NCU
文摘The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,Phobos.The physical nature of these"Phobos events"is examined using results from related investigations over the last twenty years.It is concluded that there is no clear evidence at present to support the association of magnetic field disturbances in the solar wind with Phobos.The situation will be further clarified taking advantage of the multi-spacecraft observations of the Yinghuo-1(YH-1),Mars Express and MAVEN missions beginning in 2012.It is expected that many novel features of solar wind interaction with Phobos(and possibly also Deimos) itself will also be revealed.
