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Near‐infrared observations of the Pluto Charon system were captured with the Palomar High Angular Resolution Observer (PHARO) adaptive optics (AO) system on the 200‐inch Hale telescope during the historically small solar phase angles in 2018–2019. Both objects exhibit large opposition surges of ∼30%–35% in the last half degree of solar phase angle, which is among the largest observed for icy moons and other Kuiper Belt Objects. In addition, Pluto's surge is exceptionally steep. Pluto's unusual phase curve may be due to an unusual surface texture caused by seasonal volatile transport and active geologic processes. These observations enable accurate determination of Pluto's geometric albedo in the JHK filter system, which we find to be 0.86 ± 0.04, 0.59 ± 0.05, and 0.39 ± 0.04 for Pluto, respectively, and 0.68 ± 0.06 for Charon in the J filter. Plain Language Summary: The New Horizons spacecraft revealed Pluto to be a geologically active, complex world. It never observed small solar phase angles, when the disk of Pluto is fully illuminated. In 2018 and 2019, Pluto reached a historically small solar phase angle that will not be repeated for 161 years. Observations at Palomar Observatory show that both hemispheres of Pluto, as well as its main moon Charon, exhibit a surge of over 30% in brightness at opposition, suggesting an unusual surface texture due to activity and volatile transport. Key Points: Pluto reached an historically small solar phase angle that will not be repeated for 161 years and that complements New Horizons observationsObservations with the adaptive optics system at Palomar Observatory during this time successfully captured both hemispheres of PlutoPluto exhibits an unusually large opposition surge that may be due to active geology and an unusual surface texture [ABSTRACT FROM AUTHOR]

Background The importance of hyperphagia as a cause for energy imbalance in humans with Bardet- Biedl syndrome ( BBS) has not been established. We therefore compared hyperphagic symptoms in patients with BBS vs. controls. Methods: We studied 13 patients with BBS and 23 non-syndromic controls with similar age, sex and body mass index ( BMI) z-score. A 13-item hyperphagia questionnaire was completed by patients' parents/guardians. Results Total hyperphagia questionnaire score was higher in BBS than controls (27.6 ± 9.0 vs. 19.1 ± 7.9, P = 0.005). Behaviour and drive subscales were higher for BBS than controls (12.5 ± 4.1 vs. 7.8 ± 3.2, P = 0.001, and 11.2 ± 4.1 vs. 8.3 ± 3.8, P = 0.04, respectively); severity was not significantly different between groups (3.8 ± 1.5 vs. 3.0 ± 1.3, P = 0.072). After adjustment for demographic variables and BMI z-score, total and behaviour subscale scores remained significantly different between groups, suggesting food-seeking activity, rather than preoccupation with food may be the main hyperphagic feature among patients with BBS. Conclusion Appetite dysregulation may contribute to obesity in BBS. [ABSTRACT FROM AUTHOR]