无碰撞激波是空间中常见的现象，它能将太阳风粒子和由行星周围中性粒子电离形成的新生带电离子加速到很高的能量，也会对行星际空间和行星空间环境造成剧烈影响。基于空间卫星的观测数据，在金星、地球、木星、土星和天王星附近都有大量的行星际激波观测数据，但是目前还没有在火星附近比较完整的行星际激波观测样本。此外，大部分的空间观测卫星都处在纯净的太阳风中，我们对纯净太阳风中的行星际激波的性质了解的比较清楚，但是对处在行星环境中的行星际激波的特征却知之甚少。本论文利用火星大气与挥发物演化探测器（MAVEN）在火星上游的等离子体和磁场观测数据，详实证认并记录了从2014年10月到2018年11月接近4.1年时间内出现在火星上游环境中的行星际激波以及它们的驱动源，并计算了激波及其驱动源的基本参数，建立了完整的出现在火星上游环境中的行星际激波及其驱动源的数据库。基于这些样本，我们全面的研究了在火星上游等离子体环境中传播的行星际激波的基本特征，行星际激波从1 AU传播到火星轨道附近过程中的演化，以及火星环境对行星际激波的影响。本文的主要工作如下： 

      1. 为了研究由太阳风高速流与低速流相互作用区（SIR）驱动的行星际激波的特征，我们系统地证认了在2014年10月到2018 年11月传播到火星轨道附近（平均距离为1.52 AU）的SIR。在这段时间内，MAVEN一共观测到149个SIR事件，我们选其中数据质量较好的126个SIR用来研究。发现在1.52 AU附近SIR的发生率为每年36.3个，比1 AU处的每年32.4个略高一点，说明大部分的SIR在1 AU处已经形成。1.52 AU附近的SIR的平均持续时间为37小时，与1 AU处的36.73小时几乎相等，表明SIR传播到1.52 AU时没有加速膨胀。从1 AU到1.52 AU，SIR的最大磁场强度和总压强明显下降，表明SIR的强度有所降低。SIR从1 AU演化到1.52 AU，其边界处的激波发生率从20.3%上升到33.3%以上。前向激波发生率是后向激波发生率的2倍。从1 AU到1.52 AU，激波强度变弱，而激波的传播速度几乎没有改变。

      2. 除了研究由SIR驱动的行星际激波之外，我们还研究了由不同驱动源驱动的行星际激波。我们重新对这段时间内的数据进行遍历，一共证认了52个行星际激波，包含39个前向激波和13个后向激波。发现大部分（79%）的前向激波是由SIR 驱动，只有少数几个是由行星际日冕物质抛射（ICME）驱动；所有的后向激波都是由SIR驱动的。92%的激波是准垂直激波。平均来看，SIR驱动的前向激波和后向激波的激波强度大致相同，而且都强于ICME驱动的前向激波。激波强度对火星弓激波上游的观测位置没有系统的依赖性。

      3. 此外，我们还研究了火星环境对行星际激波形状的影响，但是并没有找到证据表明作为传播介质中障碍物的火星及其弓激波影响了传播到其附近的行星际激波的形状。

      这些结果能帮助我们了解在不同传播环境中的行星际激波的性质，也有助于我们了解火星上游的太阳风条件以及它们对火星空间环境的潜在影响。除此之外，我们建立的行星际激波数据库为日后研究火星上游环境中的等离子体结构对行星际激波的具体影响，以及行星际激波对火星空间环境的影响打下了很好的基础。

Collisionless shocks are ubiquitous in the space. It can accelerate the solar wind particles and new-born ions ionized from the neutral components around planets to very high energy. In addition, they have great impacts to the interplanetary space and planetary space environments. There have been large amounts of interplanetary (IP) shock cases observed by spacecrafts near Venus, Earth, Jupiter, Saturn and Uranus. Up to now, however, there is no complete IP shock samples observed near Mars due to the lack of observations. In addition, most spacecrafts are observing in the pristine solar wind, which makes us understand the properties of IP shocks in pristine solar wind very well, but the properties of IP shocks in the planetary environment are less understood. Based on the plasma and magnetic field data observed by Mars Atmosphere and Volatile EvolutioN mission (MAVEN), we clearly identified and recorded the IP shocks and their drivers propagating in the upstream environment of Mars from October 2014 to November 2018, calculated their basic parameters, and built complete data bases of IP shocks and their drivers. Based on these samples, we then study the characteristics of IP shocks propagating in the plasma environment upstream from Mars, the evolution of IP shocks from 1 AU to the Mars’ orbit, and the effects of Martian environment to IP shocks. The main works of this thesis are as follows:

1. To study the properties of IP shocks driven by stream interaction regions (SIRs), we systematically identified the SIRs propagated to the Mars’ orbit (1.52 AU on average). A total of 149 SIRs are identified during the period from October 2014 to November 2018, and 126 SIRs with high-quality data are selected for this study. We find that the average occurrence rate of SIRs at 1.52 AU is 36.3 per year, which is comparable to but slightly higher than that (32.4 per year) at 1 AU, meaning that most SIRs are well formed at 1 AU. The average duration of SIRs at 1.52 AU is about 37.0 hours, comparable to that at 1 AU (36.73 hours), indicating that SIRs have not yet expanded more rapidly as they are convected to 1.52 AU. The maximum magnetic field strength and pressure of SIRs decrease significantly from 1 to 1.52 AU, indicating that the intensity of the SIRs has decreased. The shock association rates of SIRs increase from 20.3% to 33.3% or higher as SIRs evolve from 1 to 1.52 AU. The forward shocks tend to occur twice more frequently than the reverse shocks. The strength of the shocks becomes weaker and the average shock speed remains almost unchanged from 1 to 1.52 AU.

2. In addition to studying the IP shocks driven by SIRs, we also study the IP shocks driven by different drivers. We traversed the observations during this period again and identified 52 IP shocks in total, including 39 forward shocks and 13 reverse shocks. We find that most (79%) of the forward shocks are driven by SIRs with only a few cases being driven by interplanetary coronal mass ejections (ICMEs), and all the reverse shocks are driven by SIRs. 92% of the identified shocks are quasi-perpendicular shocks. On average, the shock strengths of SIR-driven forward and reverse shocks are comparable, and they are stronger than that of ICME-driven forward shocks. The shock strengths show no systematic dependence on the shock locations relative to the Martian bow shock. 

3. In addition, we have also studied the influence of the Mars on the shape of IP shocks, but have found no evidence that the shock shapes are affected by Mars and its bow shock as an obstacle in the propagating medium.

The results can help us understand the nature of IP shocks propagating in different environments, as well as the solar wind conditions at Mars and their potential impact on the Martian space environment. In addition, the IP shock data base makes a good foundation for study the detail effects of plasma structures upstream from Mars on the IP shocks and the effects of IP shocks on Martian space in the future.