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HST observations taken less than a month before the Mid-Cycle deadline show that a secondary dark feature has appeared on Neptune comma closer to the equator than the main dark vortex known as NDS-2018. We propose deep imaging in the F467M filter that is ideal for detecting dark features comma which cannot be seen at infrared wavelengths only HST has the short wavelength spatial resolution capable of observing these spots. New observations are needed to constrain the evolution of NDS-2018 and the recently-discovered secondary dark feature comma given the limited information currently available on these storms. Results from the proposed study would constrain future modeling efforts and lay groundwork for potential Neptune spacecraft missions in the coming decades. Infrared JWST observations of Neptune in 2022 will be blind to NDS-2018 and any secondary dark features comma but the JWST observations are intended to characterize any localized compositional or thermal anomalies associated with storms or other discrete features. The proposed HST observations would enhance the interpretation of JWST data by showing whether NDS-2018 is still present at the time of the JWST observations comma and whether any secondary dark features (either localized or global-scale) are present. We seek to explore five key questionsdoublePoint What is the dynamical nature of secondary dark featuresquestionMark How do secondary dark features influence the north-south migration of the dark vortexquestionMark What does vortex migration tell us about the background atmospherequestionMark Are Jupiter-Saturn vortices different from Neptune.s dark spotsquestionMark What global-scale effects are produced by dark vorticesquestionMark