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This is the second part of Stolzenbach et al. (2023, https://doi.org/10.1029/2022JE007276), named hereafter Paper I, extends the period to the end of MY 34 and the first half of MY 35. This encompasses the end phase of the MY 34 Global Dust Storm (GDS), the MY 34 C‐Storm, the Aphelion Cloud Belt (ACB) season of MY 35, and an unusual early dust event of MY 35 from LS30° to LS55°. The end of MY 34 overall aerosol size distribution shows the same parameters for dust and water ice to what was seen during the MY 34 GDS. Interestingly, the layered water ice vertical structure of MY 34 GDS disappears. The MY 34 C‐Storm maintains condition like the MY 34 GDS. A high latitude layer of bigger water ice particles, close to 1 μm, is seen from 50 to 60 km. This layered structure is linked to an enhanced meridional transport characteristic of high intensity dust event which put the MY 34 C‐Storm as particularly intense compared to non‐GDS years C‐Storms as previously suggested by Holmes et al. (2021, https://doi.org/10.1016/j.epsl.2021.117109). Surprisingly, MY 35 began with an unusually large dust event (Kass et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AGUFMP039…01K) found in the Northern hemisphere during LS35° to LS50°. During this dust event, the altitude of aerosol first detection is roughly equal to 20 km. This is close to the values encountered during the MY 34 GDS, its decay phase and the C‐Storm of the same year. Nonetheless, no vertical layered structure was observed. Mars has a peculiar tendency, in one in every three Martian year, the entire planet is covered by dust suspended in the atmosphere. These events are referred as Global Dust Storms (GDS). The dust is lifted by fierce winds from the ground up to 80 km high. The mixture of water ice crystals and dust particle in the air of Mars change how the incoming Sun light warms the atmosphere. It is then of a crucial importance to properly characterize the nature and size of the aerosols, especially during a GDS, to better understand the dynamics of the Martian atmosphere. The spacecraft (ESA/Roscosmos) ExoMars Trace Gas Orbiter has been studying the Martian atmosphere since April 2018 and observed a GDS but also other and less intense dust storms. These data help us distinguish the aerosols nature (dust and water ice) and sizes during these distinct types of dust events. Our study confirms that, globally, the particles of dust and water ice are quite small, close to 1 μm or even less. Their distribution varies a lot, meaning that one may find a lot of different particle sizes or lot of similar sized particles. MY 34 C‐Storm aerosol effective size and vertical structure is similar to MY 34 Global Dust Storm (GDS)MY 35 early dust event aerosol shows similar effective size and vertical structure as MY 34 GDSMY 34 GDS leads to more intense C‐Storm and an unusual early storm at the start of MY 35 MY 34 C‐Storm aerosol effective size and vertical structure is similar to MY 34 Global Dust Storm (GDS) MY 35 early dust event aerosol shows similar effective size and vertical structure as MY 34 GDS MY 34 GDS leads to more intense C‐Storm and an unusual early storm at the start of MY 35

Since the beginning of the Trace Gas Orbiter (TGO) science operations in April 2018, its instrument “Nadir and Occultation for MArs Discovery” (NOMAD) supplies detailed observations of the IR spectrums of the Martian atmosphere. We developed a procedure that allows us to evaluate the composition and distribution's parameters of the atmospheric Martian aerosols. We use a retrieval program (RCP) in conjunction with a radiative forward model (KOPRA) to evaluate the vertical profile of aerosol extinction from NOMAD measurements. We then apply a model/data fitting strategy of the aerosol extinction. In this first article, we describe the method used to evaluate the parameters representing the Martian aerosol composition and size distribution. MY 34 GDS showed a peak intensity from LS190° to 210°. During this period, the aerosol content rises multiple scale height, reaching altitudes up to 100 km. The lowermost altitude of aerosol's detection during NOMAD observation rises up to 30 km. Dust aerosols reffwere observed to be close to 1 μm and its νefflower than 0.2. Water ice aerosols reffwere observed to be submicron with a νefflower than 0.2. The vertical aerosol structure can be divided in two parts. The lower layers are represented by higher reffthan the upper layers. The change between the lower and upper layers is very steep, taking only few kilometers. The decaying phase of the GDS, LS210°–260°, shows a decrease in altitude of the aerosol content but no meaningful difference in the observed aerosol's size distribution parameters. Mars' atmosphere is filled with dust and water ice particles carried by the winds. These aerosols affect the way sunlight is distributed in the atmosphere and on the surface, and this directly affects temperature. In addition, approximately every three Martian years, Mars experiences what is known as a “global dust storm.” This type of dust storm covers the entire red planet in dust. It affects the temperature and water vapor content of the Martian atmosphere. Determining and assessing aerosol properties, number, size and mass during and after a global dust storm is of crucial importance to understanding its underlying mechanisms. Here, we develop an analysis scheme to study the size, nature, number and distribution of Martian aerosols. Our study confirms that, overall, dust and water ice particles are quite small, close to 1 μm or even smaller, and that a global dust storm affects the intensity of other storms that follow. Retrieval of Martian aerosols key properties from NOMAD‐SO data during the MY 34 GDSMesospheric dust and water ice reffare mainly ∼1 μm and ≤0.5 μm respectively during the MY 34 GDS and its decay phaseDuring the MY 34 GDS, the effective variance shows a slight N/S asymmetry and values mainly ≤0.2 Retrieval of Martian aerosols key properties from NOMAD‐SO data during the MY 34 GDS Mesospheric dust and water ice reffare mainly ∼1 μm and ≤0.5 μm respectively during the MY 34 GDS and its decay phase During the MY 34 GDS, the effective variance shows a slight N/S asymmetry and values mainly ≤0.2

We present a new planetary nebula, first identified in images from the Australia Telescope Compact Array, although not recognized at that time. Recent observations with the Spitzer Space Telescope during the GLIMPSE Legacy program have rediscovered the object. The high-resolution radio and infrared images enable the identification of the central star or its wind, the recognition of the radio emission as thermal, and the probable presence of polycyclic aromatic hydrocarbons in and around the source. These lead to the conclusion that G313.3+00.3 is a planetary nebula. This object is of particular interest because it was discovered solely through radio and mid-infrared imaging, without any optical (or near-infrared) confirmation, and acts as a proof of concept for the discovery of many more highly extinguished planetary nebulae. G313.3+00.3 is well resolved by both the instruments with which it was identified and suffers extreme reddening due to its location in the Scutum-Crux spiral arm.