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As an end-member of terrestrial planet formation, Mercury holds unique clues about the original distribution of elements in the earliest stages of solar system development and how planets and exoplanets form and evolve in close proximity to their host stars. The importance of in situ measurements via a landed mission to Mercury was recognized by the 2013–2022 Decadal Survey, and again with its selection for a Planetary Mission Concept Study in support of the 2023–2032 Decadal Survey. Mercury is the only inner planet unexplored by a landed spacecraft; landing on Mercury is uniquely challenging due to the large $\Delta\mathrm{V}$ requirements and extreme thermal environment for such a mission. This paper describes the mission concept design that meets those challenges by leveraging recent technology advances including increased launch vehicle performance capability, further development and use of solar electric propulsion (SEP), and Next-Generation radioisotope thermoelectric generator (NextGen RTG) development. These advances enable a New-Frontiers-class mission concept which achieves one full Mercury year (∼88 Earth days) of surface operations with an 11-instrument, high-heritage payload that is delivered to a landing site within Mercury's widely distributed low-reflectance material, and addresses science goals encompassing geochemistry, geophysics, the Mercury space environment, and geology. The mission concept presented here addresses the primary challenges of a Mercury Lander mission with a four-stage design that launches on an expendable Falcon Heavy vehicle. Mass savings are enabled through jettisoning of stages prior to large burns and optimization of propulsion systems for each phase: cruise, orbit, initial descent, and landing. The flight system utilizes an SEP cruise stage to reach Mercury and jettisons this stage prior to the Mercury orbit insertion (MOI) burn. MOI and orbit-lowering maneuvers are executed with a large bipropellant propulsion system on an orbital stage. During the orbital phase, a narrow-angle camera acquires images for final selection of a low-hazard landing zone within the region of interest. The orbital stage is jettisoned just prior to descent. A solid rocket motor (SRM) descent stage executes the braking burn, and final landing is performed following SRM burnout and jettison with the Lander's bipropellant propulsion system and continuous LIDAR operations to support hazard detection. Landing occurs at dusk to meet thermal requirements, permitting ∼30 hours of sunlight for initial observations. The NextGen RTG powered lander continues operations through the Mercury night. Direct-to-Earth (DTE) communication is available for the initial three weeks of landed operations, unavailable for the following six weeks, and resumes for the final month. Thermal conditions exceed lander operating temperatures shortly after sunrise, ending operations. A total of ∼11 GB of data are returned to Earth.

The NASA Double Asteroid Redirection Test (DART) is a technology demonstration mission that will test the kinetic impactor technique on a binary near-Earth asteroid system, Didymos. Didymos is an ideal target, since the 780 m primary, Didymos A, is well characterized, and the 163 m secondary, Didymos B, is sufficiently small to allow measurement of the kinetic deflection. Didymos also represents the population of Near Earth Objects that are the asteroids most likely to pose a near-term threat to Earth. Scheduled to launch in June 2021, the DART spacecraft will autonomously intercept Didymos B in October 2022, altering the orbit period of Didymos B with respect to Didymos A. The impact will occur when the Earth-Didymos range is close enough to allow observation by Earth-based optical and radio telescopes. The spacecraft will be guided to the impact by its on-board autonomous real-time system Small-body Maneuvering Autonomous Real-Time Navigation (SMART Nav). In addition, DART is carrying a 6U CubeSat provided by Agenzia Spaziale Italiana (ASI). The CubeSat will provide imagery documentation of the impact, as well as in situ observation of the impact site and resultant ejecta plume. The development is currently in Phase C, with mission Critical Design Review (CDR) planned for summer 2019. It is a substantial challenge to navigate the DART spacecraft to a hypervelocity impact with the Didymos secondary. The DART spacecraft will carry an ion propulsion system with the NASA Evolutionary Xenon Thruster Commercial (NEXT-C)engine, which provides flexibility in trajectory design to achieve the desired Didymos arrival conditions. The trajectory maximizes the asteroid deflection with an arrival velocity of 6 km/s relative to Didymos-B, while maintaining a proximity to Earth that allows both observation of the impact, and sufficient communication gain to recover imagery of the target upon the approach. Additionally, NEXT-C allows the mission an opportunity to fly by another asteroid and characterize SMART Nav performance seven months prior to its use for the Didymos impact. The DART spacecraft carries 22 m2 solar arrays to generate the ~3.5 kW needed to power the NEXT-C engine. These long arrays introduce substantial flexible body motion to the spacecraft. This motion must be managed carefully to maintain the DART narrow angle camera on the target asteroid, even while performing the necessary autonomous ΔV maneuvers required to intercept the target. Guidance to Didymos B is further complicated by having to switch targets late in the approach, as SMART Nav must target the primary asteroid initially, as the secondary is too small to be resolved by the narrow angle camera until ~1 hour prior to impact. Shadowing of both primary and secondary set by arrival lighting makes it challenging to impact at the center of Didymos B. The spacecraft streams images back to Earth in real time, up until impact.

Carrier-based linear transport sputter deposition systems are routinely used in the silicon photovoltaic (PV) cell industry owing to the demonstrated usefulness of such systems in the High Volume Manufacturing (HVM) of silicon PV cells, where throughputs of thousands of wafers per hour are expected, and where Cost-of-Ownership (COO) differences of pennies per PV wafer can make or break a manufacturer. The metals being sputter deposited for silicon PV cells are typically some combination of Ti, TiW, Al, and Cu — the same materials that the Advanced Packaging industry uses for barrier/seed structures in Cu Redistribution Layers (RDL). In Fan-Out Wafer Level Packaging (FOWLP) today, cluster tool architectures from front-end semiconductor fabrication are the Process-of-Record (POR) configuration for RDL barrier and seed deposition. We present here details about barrier/seed layer processes for Fan-Out RDL developed on a carrier-based linear transport Physical Vapor Deposition (PVD) system, including metal film uniformity, sheet resistance, and film adhesion results for both 300mm round fan-out wafers and for 600mm × 600mm square fan-out panels. We also present our analysis of system throughput, PVD target utilization, and overall COO, as compared to the metrics characteristic of a typical PVD cluster tool.