We present the results from four stellar occultations by (486958) Arrokoth, the flyby target of the New Horizons extended mission. Three of the four efforts led to positive detections of the body, and all constrained the presence of rings and other debris, finding none. Twenty-five mobile stations were deployed for 2017 June 3 and augmented by fixed telescopes. There were no positive detections from this effort. The event on 2017 July 10 was observed by SOFIA with one very short chord. Twenty-four deployed stations on 2017 July 17 resulted in five chords that clearly showed a complicated shape consistent with a contact binary with rough dimensions of 20 by 30 km for the overall outline. A visible albedo of 10% was derived from these data. Twenty-two systems were deployed for the fourth event on 2018 Aug 4 and resulted in two chords. The combination of the occultation data and the flyby results provides a significant refinement of the rotation period, now estimated to be 15.9380 ± 0.0005 hours. The occultation data also provided high-precision astrometric constraints on the position of the object that were crucial for supporting the navigation for the New Horizons flyby. This work demonstrates an effective method for obtaining detailed size and shape information and probing for rings and dust on distant Kuiper Belt objects as well as being an important source of positional data that can aid in spacecraft navigation that is particularly useful for small and distant bodies.

RECON is a citizen-science telescope network designed to observe high-uncertainty occultations by outer solar system objects. Adopting circular models for the object profiles, we derive a radius =-+ r 16 1 2 km and a geometric albedo =-+ p 0.13 V 0.024 0.015 for 2014 YY 49 and a radius =-+ r 66 5 5 km and a geometric albedo =-+ p 0.045 V 0.008 0.006 for 2013 NL 24. To the precision of these measurements, no atmosphere or rings are detected for either object. The two objects measured here are among the smallest distant objects measured with the stellar occultation technique. In addition to these geometric constraints, the occultation measurements provide astrometric constraints for these two Centaurs at a higher precision than has been feasible by direct imaging. To supplement the occultation results, we also present an analysis of color photometry from the Pan-STARRS surveys to constrain the rotational light curve amplitudes and spectral colors of these two Centaurs. We recommend that future work focus on photometry to more deliberately constrain the objects' colors and light curve amplitudes and on follow-on occultation efforts informed by this astrometry.

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A stellar occultation by the extreme large-perihelion trans-Neptunian object (541132) Leleākūhonua (also known by the provisional designation of 2015 TG387) was predicted by the Lucky Star project and observed with the Research and Education Collaborative Occultation Network on 2018 October 20 UT. A single detection and a nearby nondetection provide constraints for the size and albedo. When a circular profile is assumed, the radius is km, corresponding to a geometric albedo , for an adopted absolute magnitude of H V  = 5.6, typical of other objects in dynamically similar orbits. The occultation also provides a high-precision astrometric constraint.

Research focused on minoritized communities has predominantly been conducted by individuals associated with universities who have little connection to or investment in these communities beyond their research agenda. Oftentimes, this research benefits the researcher more than the community. This study of a peer‐taught, prison‐based, adult language, and literacy program challenged traditional research paradigms through the implementation of participatory action research (PAR). Informed by PAR epistemologies, the research team, composed of the incarcerated peer‐instructors and a university volunteer, employed qualitative methodologies over an 18‐month period to better understand how the program was experienced by its different members in relation to classroom practices and policies. We examine how PAR provided a reflexive space for us to examine our shifting subjectivities as members and researchers in the program while also challenging our understandings of the experiences of program members. Additionally, this study calls for a broader consideration of how change is defined.