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Auroras can be regarded as the most fascinating manifestation of space weather and they are continuously observed by ground‐based and, nowadays more and more, also by space‐based measurements. Investigations of auroras and geospace comprise the main research goals of the Suomi 100 nanosatellite, the first Finnish space research satellite, which has been measuring the Earth's ionosphere since its launch on 3 December 2018. In this work, we present a case study where the satellite's camera observations of an aurora over Northern Europe are combined with ground‐based observations of the same event. The analyzed image is, to the authors' best knowledge, the first auroral image ever taken by a CubeSat. Our data analysis shows that a satellite vantage point provides complementary, novel information of such phenomena. The 3D auroral location reconstruction of the analyzed auroral event demonstrates how information from a 2D image can be used to provide location information of auroras under study. The location modeling also suggests that the Earth's limb direction, which was the case in the analyzed image, is an ideal direction to observe faint auroras. Although imaging on a small satellite has some large disadvantages compared with ground‐based imaging (the camera cannot be repaired, a fast moving spinning satellite), the data analysis and modeling demonstrate how even a small 1‐Unit (size: 10 × 10 × 10 cm) CubeSat and its camera, build using cheap commercial off‐the‐shelf components, can open new possibilities for auroral research, especially, when its measurements are combined with ground‐based observations. Plain Language Summary: Auroras, or polar lights, have been imaged by ground‐based terrestrial cameras for a long time. However, auroras can also be observed from space with cameras mounted on spacecraft. In the last few years, a number of very small satellites, so‐called nanosatellites with masses less than 10 kg, have been developed and launched into so‐called low Earth orbits at altitudes between 300 and 600 km. These small and light satellites are much cheaper than traditional large and heavy satellites, the masses of which could easily exceed hundreds of kilograms. Therefore, it is anticipated that nanosatellites will provide new possibilities to investigate auroras. In this study, we analyze, to our knowledge, the first image of an aurora taken by a nanosatellite. The satellite is a small, 10 × 10 × 10 cm, Suomi 100 satellite which was launched in December 2018. We show how the obtained auroral image can provide new information about auroras when it is combined with ground‐based observations and numerical modeling. When additional cameras will be included in the design and fabrication of small satellites, we will be able to increase our understanding of auroras and, consequently, the effects of the Sun on the Earth and beyond. Key Points: The concept of imaging aurora toward the Earth's limb by a CubeSat camera is demonstratedThe dark background available in the Earth‐limb viewing direction facilitates imaging of dim auroras, e.g., for auroral tomography purposesThe analysis shows that auroral imaging at low Earth orbit can provide a new context for ground‐based auroral and ionospheric observations [ABSTRACT FROM AUTHOR]

This work aims to provide details on the latest technological developments regarding LiDAR (Light Imaging Detection And Ranging) systems, with particular reference to the techniques, architectures, and methodologies partially or entirely implemented by means of the FPGA (Field Programmable Gate Array) environment. Currently, LiDAR technology is considered of great interest as it is widely employed in a variety of application fields, such as automotive, seismology, archaeology, metrology, and military. For this reason, the required performances are gradually increasing, which leads to complex and stringent solutions. The growth in LiDAR systems' complexity suggests the use of high-end general-purpose computing units such as central processing units to perform very complex tasks and FPGAs to perform multiple tasks in real-time through the implementation of dedicated computational blocks. The latter, in recent architectures, are therefore used for the execution of specific tasks that require high computational speed and system flexibility. This paper reports some case studies recently applied in the LiDAR field, with the aim of illustrating the role of FPGA technology and its benefits. [ABSTRACT FROM AUTHOR]

The Mercury Imaging X-ray Spectrometer is a highly novel instrument that is designed to map Mercury’s elemental composition from orbit at two angular resolutions. By observing the fluorescence X-rays generated when solar-coronal X-rays and charged particles interact with the surface regolith, MIXS will be able to measure the atomic composition of the upper ∼10-20 μm of Mercury’s surface on the day-side. Through precipitating particles on the night-side, MIXS will also determine the dynamic interaction of the planet’s surface with the surrounding space environment. MIXS is composed of two complementary elements: MIXS-C is a collimated instrument which will achieve global coverage at a similar spatial resolution to that achieved (in the northern hemisphere only – i.e. ∼ 50 – 100 km) by MESSENGER; MIXS-T is the first ever X-ray telescope to be sent to another planet and will, during periods of high solar activity (or intense precipitation of charged particles), reveal the X-ray flux from Mercury at better than 10 km resolution. The design, performance, scientific goals and operations plans of the instrument are discussed, including the initial results from commissioning in space. [ABSTRACT FROM AUTHOR]