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This paper presents our efforts to characterize the candidate landing region (109°–133°E, 23°–30°N) for Tianwen‐1, China's first mission to Mars, in terms of engineering safety and scientific significance. Topographic analysis reveals that the region has a low elevation around −4,230 m, and 98% of the region have slopes smaller than 8°. The geomorphological mapping and analysis show that the region has an average crater density of about 28 craters (≥200 m in diameter) per 100 square kilometers, with several clusters of high crater densities distributed around the center of the region. There are also pitted cones distributed mainly in the southern part of the region, with a density of approximately 6.6 cones per 100 square kilometers in specific local areas. The region has rock abundances ranging from 1% to 23%, with local clusters of low and high rock abundances. The region comprises four main geological units, including a lowland unit formed in the Late Hesperian and a volcanic unit formed in the Amazonian and Hesperian period. Their specific surface ages are estimated through the analysis of crater size‐frequency distribution. Combining the engineering constraints on surface slopes, crater density, cone density, and rock abundance, a hazard map of the candidate landing region is generated for landing site evaluation and safety assessment. Based on the results, we further discuss the potential scientific outcomes from the exploration in this region. The findings will be helpful for the mission planning and maximization of the scientific return from Tianwen‐1, and complement existing Martian scientific research. Key Points: Topographic, geomorphological, and geologic characterization of the candidate landing region of Tianwen‐1A hazard map of the region combining engineering constraints on slopes, crater density, cone density, and rock abundanceTwo local areas in the region are highlighted as potential landing sites for their low hazard and scientific significance [ABSTRACT FROM AUTHOR]

China's first Mars sampling return mission (Tianwen‐3) is designed to launch and retrieve samples around 2030. Three tentative landing areas (TLAs) (Amazonis, Chryse and Utopia Planitiae, i.e., TLA‐A, TLA‐C and TLA‐U) are selected based on elevation <−2,000 m and latitude between 17° and 30°N. As a dominant feature of Martian meteorology, dust storms manifest in all seasons and affect the accuracy and safety of Mars exploration missions. Tianwen‐3's landing, sampling and ascent phases are in the dust storm season. Therefore, analyzing dust storm activity around landing areas is significant for the Tianwen‐3 mission. According to Mars Daily Global Maps taken by Mars Orbiter Camera spanning Martian years 24–28, 2,476 dust storm events around the three TLAs were identified in this research. Dust storm temporal probabilities within TLA‐A, TLA‐C and TLA‐U were calculated as 0%–44.69%, 0%–66.29% and 0%–33.64%, separately. Dust storm spatial probabilities around the TLA‐A, TLA‐C and TLA‐U were computed, with ranges of 0%–10.71%, 0%–14.55% and 0%–19.96% during the T1 period (Ls = 161–309°), and 0%–6.75%, 0%–7.65% and 0%–8.26% during the T2 period (Ls = 342‐55°), respectively. Finally, considering the temporal and spatial distribution of dust storms, we recommend the T2 period as the launch scenario. Three safe periods (Ls = 2–18°, 4–12°, and 356–4°) were assigned for the entry‐descent‐landing (EDL) phase, along with one period (Ls = 45–55°) for the take‐off and ascent phase. Five circular landing zones with dust storm spatial probability <3% were selected for the Tianwen‐3 mission. Plain Language Summary: Tianwen‐3 is the first Mars sampling return mission by China, scheduled to launch and return samples around 2030. Three tentative landing areas (TLAs), Amazonis Planitia (TLA‐A), Chryse Planitia (TLA‐C), and Utopia Planitia (TLA‐U), located at elevations of <−2,000 m and within the latitude range of 17°–30°N. Three TLAs are situated along the trajectories of Martian dust storm sequences. The harsh dusty conditions significantly impact the success of the Mars exploration mission. Therefore, it is meaningful to analyze the dust storm occurrence probability within and around three TLAs. In this study, we utilized Mars Global Surveyor (MGS) Mars Daily Global Maps to (a) detect the dust storm events around three TLAs in five consecutive Mars years (MY 24–28); (b) calculate and analyze the temporal and spatial probabilities of dust storm occurrence; and (c) designate the safe landing areas, the preferred take‐off and ascent and entry‐descent‐landing (EDL) periods for the Tianwen‐3 mission. Key Points: Dust storms within three tentative landing areas exhibit distinct seasonality and heterogeneity throughout a Mars year, with clear solstitial pause periodsDust storm spatial‐temporal analysis reveals that the T2 period is more suitable as the launch scenario for the Tianwen‐3The preferred entry‐descent‐landing period, preferred take‐off and ascent period, and safe landing areas are chosen for the Tianwen‐3 [ABSTRACT FROM AUTHOR]

China's first Mars exploration mission (Tianwen‐1), launched on July 23, 2020 with the goal of "orbiting, landing, and roving," and its tentative landing areas (TLAs) are Chryse Planitia (TLA 1) and Isidis‐Elysium Planitia (TLA 2). Dust storm is a typical activity on Mars; it has strong interaction with atmospheric circulation and will influence the visibility of the Martian surface. To ensure the safety and accuracy for landing, it is meaningful to analyze the probability of dust storm activity during Entry‐Descent‐Landing (EDL) season in TLAs. First, based on Mars Orbiter Camera (MOC) and Mars Color Imager (MARCI) Daily Global Maps (MDGMs) from Mars Years 24–31, we identified 882 dust storms within the 2,000 km radius monitor circle of TLA 2 (short for TLA 2‐C). Second, the average daily probability of dust storm activity (Adp_ds) in TLA 2‐C was calculated, with a range of 0% to 14.13% showing obvious seasonality and discontinuity. Third, we divided TLA 2‐C into 0.5° longitude × 0.5° latitude square grids and calculated their spatial probability of dust storm activity. The spatial probability of dust storm in TLA 2‐C ranged from 0% to 11.87% and generally reduced from north to south. Finally, according to the temporal and spatial dust storm probability in TLA 2 during EDL season, we suggested the optimal landing time of China's Tianwen‐1 mission was in Ls = 20–41° and selected five preferred landing areas with the spatial probability of dust storm <3% for this mission. Plain Language Summary: The first China's Mars exploration mission (Tianwen‐1), will achieve the targets of "orbiting, landing, and roving." There are two tentative landing areas (TLAs) in the latitude range of 5–30°, Chryse Planitia (TLA 1) and Isidis‐Elysium Planitia (TLA 2). TLA 2 is on the south of Utopia which is an important origination area of dust storm sequences in the northern hemisphere. The probability of dust storm activity is an important criterion of atmospheric risk assessment for a Martian surface mission. Thus, it is crucial to evaluate the probabilities and characteristics of dust storm activity in and around TLA 2. In this paper, we used Mars Daily Global Maps (MDGMs) of Mars Orbiter Camera (MOC) and Mars Color Imager (MARCI) to (1) identify and catalog the dust storms in and around TLA 2; (2) calculate and analyze the temporal and spatial probability of dust storms in and around TLA 2; and (3) select the preferred landing time and areas for Tianwen‐1 mission based on the temporal and spatial probability of dust storm activity in TLA 2. Key Points: The temporal probability of dust storm activity in Isidis‐Elysium Planitia shows obvious seasonal and inconsecutive activityThe spatial probability of dust storm activity in Isidis‐Elysium Planitia is generally reduced from north to southThe optimal landing time was in Ls = 20–41°, and five preferred landing areas were selected for Tianwen‐1 [ABSTRACT FROM AUTHOR]