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The Curiosity Rover has been exploring the Gale Crater using the on‐board Navigation Camera to monitor the line‐of‐sight (LOS) dust extinction within the crater. Previous studies of the line‐of‐sight extinction have shown an annual trend where a minimum in extinction occurs around Ls = 100° and a maximum occurs around Ls = 300°. However, past studies have been constrained to images acquired only between 10:00 and 14:00 local time, limiting our understanding of the variation of dust extinction in Gale Crater throughout the day. Here, using a method that corrects for variable lighting geometry, we reanalyze the line‐of‐sight images captured throughout the mission to include images acquired in the early morning and late afternoon. Additionally, we update the line‐of‐sight record to include over 1,000 additional sols of the mission through sol 3,663, which updates our record of extinction in Gale to the end of Mars Year 36—a period of almost 5.5 Mars Years. Using images taken throughout the sol, we examine the diurnal trend in dust extinction, where a maximum is seen around solar noon. This diurnal trend is observed throughout the year, with a larger diurnal variation observed during the southern summer. Additionally, the geographic homogeneity in dust loading is quantified, with higher dust loading observed in the western portion of the line‐of‐sight images, corresponding with the north‐western portion of the crater rim. These observations suggest that dust lifting from the surface and vertical mixing are factors in the diurnal, seasonal, and geographic dynamics observed in the extinctions. Plain Language Summary: The Curiosity Rover has used its Navigation Camera to image the northern rim of Gale Crater for over 3,000 martian days. These images are used to calculate the amount of airborne dust between the rover and the crater rim. Past studies using these images found that the amount of dust was lowest during southern‐hemisphere winter and highest during southern‐hemisphere summer. In this work, a new method to find the amount of dust was used, allowing us to use images taken throughout the day for the first time. The entire set of crater rim images was reanlayzed using the new method, including new images captured up to sol 3,663. We find a daily cycle, where the amount of dust in the air is lowest in the morning and evening, and highest around noon. In addition, there is more airborne dust between the rover and the crater rim on the western side of the image compared with the center and eastern side. This suggests that dust is moving within the Gale Crater on short timescales, where dust lifting from the surface likely plays a key role in the diurnal trend, in combination with air outside the crater mixing with air within the crater. Key Points: The line‐of‐sight dust extinction is calculated through 3,663 sols using the Mars Science Laboratory's Navigation CameraDiurnally, the dust extinction peaks at solar noon, with lower values in the morning and eveningThe diurnal variation is higher during the dustier southern summer and lower during the southern winter when dust extinction is at a minimum [ABSTRACT FROM AUTHOR]

We use in situ environmental measurements by the Mars Science Laboratory (MSL) mission to obtain the surface energy budget (SEB) across Curiosity's traverse during the first 2500 sols of the mission. This includes values of the downwelling shortwave solar radiation, the upwelling solar radiation reflected by the surface, the downwelling longwave radiation from the atmosphere, the upwelling longwave radiation emitted by the surface, the sensible heat flux associated with turbulent motions, and the latent heat flux associated with water phase changes. We then analyze their temporal variation on different timescales and relate this to the mechanisms causing these variations. Through its Rover Environmental Monitoring Station, MSL allows for a more accurate determination of the SEB than its predecessors on Mars. Moreover, the unprecedented duration, cadence, and frequency of MSL environmental observations allow for analyses of the SEB from diurnal to interannual timescales. The results presented in this article can be used to evaluate the consistency with predictions from atmospheric numerical models, to validate aerosol radiative properties under a range of dust conditions, to understand the energy available for solar‐powered missions, and to enable comparisons with measurements of the SEB by the Perseverance rover at Jezero crater. Plain Language Summary: The primary energy input at the Martian surface is the solar radiation, which depends on the time of the day and season, geographical location (latitude and altitude), and atmospheric dust and gas abundances. Another energy input is the thermal atmospheric forcing, which depends on the vertical distribution of dust and water ice aerosols as well as CO2 and H2O molecules. Together with the reflected solar radiation and the thermal radiation emitted by the surface, these four terms make up the net radiative forcing of the surface. In response to it, energy outputs as turbulent motions and water phase changes emerge to cool down/warm up the ground. The remaining energy is available to control the thermal environment in the surface and shallow subsurface through conduction into the soil. By using first‐of‐their‐kind measurements from the Mars Science Laboratory mission, we calculate the energy inputs and outputs across Curiosity's traverse over the first 2500 Martian days of the mission. We then analyze their temporal variations and relate this to the mechanisms causing such variations. An accurate determination of the surface energy budget is key to preparing for the human exploration of Mars because it contributes to improvements in the predictive capabilities of numerical models. Key Points: We have calculated each term of the surface energy budget during the first 2500 sols of the Mars Science Laboratory missionWe have analyzed the variation of each term from diurnal to interannual timescales in relation to the mechanisms causing the variationsOur results are important in preparation for the human exploration of Mars to evaluate the consistency with predictions from models [ABSTRACT FROM AUTHOR]

Mars' planet‐encircling or global dust storms (GDSs) are an iconic and enigmatic feature of the Red Planet. Occurring every few Mars Years (MYs), on average, they are a stochastic process in the otherwise largely repeatable annual cycle of martian weather. In 2018 (MY 34 in the calendar of Clancy et al. [2000], https://doi.org/10.1029/1999je001089), an international fleet of spacecraft–six orbiters and two rovers–observed the most recent GDS. This introduction and the articles of this special collection describe the evolution and impacts of the storm from the surface to the exosphere, compare this storm to previous GDSs, identify new phenomena never previously seen in such storms, and attempt to determine how and when GDSs develop. Plain Language Summary: Mars' planet‐encircling or global dust storms are an iconic and enigmatic feature of the Red Planet. Occurring every few Mars Years, on average, they are a seemingly random process in the otherwise largely repeatable annual cycle of martian weather. In 2018, an international fleet of spacecraft, six orbiters and two rovers, observed the most recent global dust storm. This introduction and the articles of this special collection describe the evolution and impacts of the storm from the surface to the top of the atmosphere and beyond, compare this storm to previous global dust storms, identify new phenomena never‐before seen in such storms, and attempt to determine how and when global dust storms develop. Key Points: Six orbiters, two rovers, and Earth‐based telescopes observed the 2018 Mars global dust stormThe 27 papers of this special collection study the storm with observations, modeling, and theoryThe 2018 storm is the most comprehensively studied Mars global dust storm to date [ABSTRACT FROM AUTHOR]

Mars' atmosphere typically supports dust aerosol with an effective radius near 1.5 μm, varying from ~1 μm during low dust times near northern summer solstice to ~2 μm during higher dust times in southern spring and summer. After global dust events, size variations outside this range have not previously been observed. We report on imaging and spectral observations by the Curiosity rover through the 2018 global dust event. These observations show that the dust effective radius was seasonally normal prior to the local onset of increased opacity, increased rapidly above 4 μm with increasing opacity, remained above 3 μm over a period of ~50 Martian solar days, then returned to seasonal values before the opacity did so. This demonstrates lifting and regional‐scale transport of a dust population ~3 times the size of typical dust aerosol. Plain Language Summary: During the global dust storm of 2018, the Curiosity rover measured the variation of atmospheric dust over time. During the onset of the dust storm, typical Martian dust was enhanced by much larger particles that were freshly lifted off the surface in distant storms and then carried to the rover site at Gale crater. The larger dust particles persisted for weeks, but fell out of the atmosphere faster than the typical dust as normal conditions were restored. Key Points: The Curiosity rover observed dust aerosol size variations through the 2018 global dust eventThe average dust radius increased above 4 μm, more than double the largest sizes previously seen with Curiosity's instrumentsThe observations demonstrate the lifting and regional‐scale transport of dust significantly larger than typical dust aerosol [ABSTRACT FROM AUTHOR]