The "middle corona" is a critical transition between the highly disparate physical regimes of the lower and outer solar corona. Nonetheless, it remains poorly understood due to the difficulty of observing this faint region (1.5-3 R☉). New observations from the GOES Solar Ultraviolet Imager in August and September 2018 provide the first comprehensive look at this region's characteristics and long-term evolution in extreme ultraviolet (EUV). Our analysis shows that the dominant emission mechanism here is resonant scattering rather than collisional excitation, consistent with recent model predictions. Our observations highlight that solar wind structures in the heliosphere originate from complex dynamics manifesting in the middle corona that do not occur at lower heights. These data emphasize that low-coronal phenomena can be strongly influenced by inflows from above, not only by photospheric motion, a factor largely overlooked in current models of coronal evolution. This study reveals the full kinematic profile of the initiation of several coronal mass ejections, filling a crucial observational gap that has hindered understanding of the origins of solar eruptions. These new data uniquely demonstrate how EUV observations of the middle corona provide strong new constraints on models seeking to unify the corona and heliosphere. Our EUV Observations and the Middle CoronaThe solar corona is the primary driver of almost all plasma dynamics throughout the solar system 1 . However, the precise nature of the connection between the corona and the heliosphere remains surprisingly poorly understood 2 . Recent solar and heliospheric observations taken by Parker Solar Probe, well within Mercury's orbit, revealed a highly structured environment shaped by flows and ejecta interacting with the corona's complex magnetic field 3,4,5,6 . The influence of these flows on the heliosphere and structural evolution

The four Solar Ultraviolet Imagers (SUVI) on board the Geostationary Operational Environmental Satellite (GOES)‐16 and GOES‐17 and the upcoming GOES‐T and GOES‐U weather satellites serve as National Oceanic and Atmospheric Administration's operational solar coronal imagers. These four identically designed solar Extreme UltraViolet instruments are similar in design and capability to the Solar Dynamics Observatory‐Atmospheric Imaging Assembly suite of solar telescopes, and are planned to operationally span two solar cycles or more, from 2017 through 2040. We present the concept of operations for the SUVI instruments, operational requirements, and constraints. The reader is also introduced to the instrument design, testing, and performance characteristics. Finally, the various data products are described along with their potential utility to the operational user or researcher.