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Utilizing Mars Atmosphere and Volatile EvolutioN (MAVEN) observations from October 2014 to May 2023, we perform a detailed survey of magnetosonic waves generated in the solar wind (refer to as upstream MS waves), with frequencies near the proton gyrofrequency in the solar wind environment. The distribution of the solar wind‐generated MS waves has been carefully investigated, including in the solar wind and in the Martian magnetosphere by propagation. The results show that these MS waves are widely distributed below the Martian bow shock but are more concentrated below the magnetic pileup boundary, particularly in the subsolar region. The waves possess higher occurrence rates on the dayside with larger amplitudes; the occurrence rates also show dusk‐side‐preferred asymmetry. The Martian crustal magnetic field can prevent MS waves from penetrating into lower altitudes, while higher solar dynamic pressure benefits their penetration. The wave amplitudes exhibit a weak positive correlation with the solar wind dynamic pressure. These obtained global distribution features of Martian upstream MS waves observed by MAVEN are valuable to improve current understanding of the dynamic variations of Martian charged particles and the underlying contribution of wave‐particle interactions driven by MS waves. Plain Language Summary: Magnetosonic waves with frequencies near the proton gyrofrequency in the solar wind environment play an important role in altering the plasma and atmospheric environment of the planet through interactions with charged particles. In this study, we statistically investigate, using Mars Atmosphere and Volatile EvolutioN observations from October 2014 to May 2023, how these waves, referred to as upstream MS waves, are distributed in the Martian space. They are found to occupy the space downstream of the bow shock but are more concentrated below the magnetic pileup boundary. Also, they are seen more frequently on the dayside and dusk side than on the other halves. The penetration of upstream MS waves becomes difficult when encountering the Martian crustal field, or when the solar dynamic pressure is lower than usual. The amplitude of waves tends to grow larger when the solar dynamic pressure increases. These results can greatly benefit studies on how charged particles can be accelerated by the waves and escape from Mars, which could profoundly change the climate of this planet. Key Points: Upstream MS waves are predominantly below the dayside magnetic pileup boundary of Mars with a dawn‐dusk asymmetry in distributionUpstream MS waves can more easily propagate to lower altitudes in the dayside regions with weak crustal magnetic field of MarsSolar wind dynamic pressure can influence the occurrence of upstream MS waves [ABSTRACT FROM AUTHOR]

The foreshock region filled with turbulences is a natural lab for studying interactions between plasma and waves. The underlying processes are vital for dissipating the energy carried by the solar wind into the Martian environment. In this study, we analyze an ultralow-frequency wave observed on 2015 August 14 by Mars Atmosphere and Volatile Evolution upstream of the Martian bow shock. The wave properties match with those of 30 s waves; the dispersion calculation shows that the upstream plasma was capable of generating the observed waves. The analysis of the ion behaviors implies the wave generated without a field-aligned beam, while the growth rate of waves seems to be modulated by the interplanetary magnetic field conditions. These results indicate the unique role of the Martian foreshock in the interaction between the solar wind and the planet. [ABSTRACT FROM AUTHOR]