火星空间环境磁场探测研究

萤火一号卫星将对火星空间环境磁场实施探测. 火星磁场对火星弓激波、磁鞘、电离层、大气等绝大多数空间环境效应都具有重要影响, 萤火一号对火星磁场的探测是通过搭载于其上的科学载荷磁强计来实现的. 此磁强计在工作原理及具体设计上, 考虑了火星轨道严酷的工作环境和科学目标所需的测量要求. 通过装星前的地面标定测试, 验证了萤火一号磁强计可以在-130~75°C温度范围内测量±256 nT以内的磁场, 分辨率可达到0.01 nT, 带宽内总噪声小于0.03 nT, 能够满足萤火一号对火星空间环境探测的需求.

Martian Space Environment Magnetic Field Investigation---High Accuracy Magnetometer

This paper presents the purpose, design and methods of the exploration of Martian Space Environmental Magnetic Field by Yinghuo-1 (YH-1). YH-1 is the first Chinese Martian Space Environment Exploration Orbiter, which would be launched with Russian spacecraft ``Phobos-Grunt' in October, 2009, and will reach Mars orbit in September, 2010. The main scientific objectives of the YH-1 mission are related with Martian space magnetic field structure and dynamic processes, and a fluxgate magnetometer was considered to be one of the most import payloads in the YH-1 orbiter. The instrument is designed to work in harsh environment around Mars orbit and to collect high resolution data in operational orbit. Two three-component fluxgate type sensors are installed in one boom with separation distance of 45 cm, and gradiometer mode is used to minimize the remnant field of platform. The boom is located at the tip of the deployable solar panel, and the distance between the center of the spacecraft and the outer sensor is about 3.2 m. The operation temperature of YH-1 magnetometer sensors is expected in the range -130~+75°C and the dynamic range is ±256 nT in 16-bit resolution. With a very low noise level below 0.01 nT·Hz-1/2, this magnetometer can measure three-component magnetic field from DC to 10 Hz. The magnetometer will work together with a Plasma Package onboard this orbiter to complete exploration of Martian space environment. The total mass of this magnetometer package is about 2.5 ,kg, and power consumption is 6.8 W.