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Abstract An internationally collaborative airborne campaign in July 2023 – led by the University of Bergen (Norway) and NASA, with contributions from many other institutions – discovered that thunderstorms near Florida and Central America produce gamma rays far more frequently than previously thought. The campaign was called Airborne Lightning Observatory for Fly’s Eye Geostationary Lightning Mapper (GLM) Simulator (FEGS) and Terrestrial Gamma-ray Flashes (TGFs), which shortens to ALOFT. The campaign employed a unique sampling strategy with NASA’s high-altitude ER-2 aircraft, equipped with gamma-ray and lightning sensors, flying near ground-based lightning sensors. Realtime updates from instruments, downlinked to mission scientists on the ground, enabled immediate return to thunderstorm cells found to be producing gamma rays. This maximized the observations of radiation created by strong electric fields in clouds, and showed how gamma-ray production may be physically linked to thunderstorm lifecycle. ALOFT also sampled storms entirely within the stereo-viewing region of the GLM instruments on GOES-16/18 and performed multiple underflights of the International Space Station Lightning Imaging Sensor (ISS LIS), while using an upgraded FEGS instrument that demonstrated the operational value of observing multiple wavelengths (including ultraviolet) with future spaceborne lightning mappers. In addition, a robust complement of airborne active and passive microwave sensors – including X- and W-band Doppler radars, as well as radiometers spanning 10-684 GHz – sampled some of the most intense convection ever overflown by the ER-2. These observations will benefit planned convection-focused NASA spaceborne missions. ALOFT is an exemplar of a high-risk, high-reward field campaign that achieved results far beyond original expectations. 

After over a decade of researcher anticipation for the arrival of persistent memory (PMem), the first shipments of 3D XPoint-based Intel Optane Memory in 2019 were quickly followed by its cancellation in 2022. Was this another case of an idea quickly fading from future to past tense, relegating work in this area to the graveyard of failed technologies? The recently introduced Compute Express Link (CXL) may offer a path forward, with its persistent memory profile offering a universal PMem attachment point. Yet new technologies for memory-speed persistence seem years off, and may never become competitive with evolving DRAM and flash speeds. Without persistent memory itself, is future PMem research doomed? We offer two arguments for why reports of the death of PMem research are greatly exaggerated. First, the bulk of persistent-memory research has not in fact addressed memory persistence, but rather in-memory crash consistency, which was never an issue in prior systems where CPUs could not observe post-crash memory states. CXL memory pooling allows multiple hosts to share a single memory, all in different failure domains, raising crash-consistency issues even with volatile memory. Second, we believe CXL necessitates a ``disaggregation'' of PMem research. Most work to date assumed a single technology and set of features, \ie speed, byte addressability, and CPU load/store access. With an open interface allowing new topologies and diverse PMem technologies, we argue for the need to examine these features individually and in combination. While one form of PMem may have been canceled, we argue that the research problems it raised not only remain relevant but have expanded in a CXL-based future.