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Abstract We present the discovery of GJ 251 c, a candidate super-Earth orbiting in the habitable zone (HZ) of its M dwarf host star. Using high-precision Habitable-zone Planet Finder and NEID RVs, in conjunction with archival RVs from the Keck I High Resolution Echelle Spectrometer, the Calar Alto High-resolution Search for M dwarfs with Exoearths with Near-infrared and optical Echelle Spectrograph, and the Spectropolarimétre Infrarouge, we improve the measured parameters of the known planet, GJ 251 b (P_b= 14.2370 days; $m\sin \left(i\right)$= 3.85 ${}_{-0.33}^{+0.35}$M_⊕), and we significantly constrain the minimum mass of GJ 251 c, placing it in a plausibly terrestrial regime (P_c= 53.647 ± 0.044 days; $m\sin i_c$= 3.84 ± 0.75M_⊕). Using activity mitigation techniques that leverage chromatic information content, we perform a color-dependent analysis of the system and a detailed comparison of more than 50 models that describe the nature of the planets and stellar activity in the system. Due to GJ 251’s proximity to Earth (5.5 pc), next generation, 30 meter class telescopes will likely be able to image terrestrial planets in GJ 251’s HZ. In fact, GJ 251 c is currently the best candidate for terrestrial, HZ planet imaging in the northern sky. 

We designed, facilitated, and re-designed an inquiry activity in an introductory undergraduate astronomy research methods course at the University of Texas at Austin over two different semesters. The teaching venue for this inquiry activity took place in the course “AST 376R: A Practical Introduction to Research Methods”, the inquiry activity was inserted into an existing course structure, taking place over multiple class periods. We discuss how we were able to leverage the Professional Development Program (PDP) inquiry themes and introduce students to specific STEM practices, using this experience as a primer or mini version of a larger research activity and research experience that they would determine and lead themselves later on in the semester. In this paper we describe the benefits for students in this course and the lessons learned by the instructors. 

In addition to educating participants about inquiry instruction, equity and inclusion in STEM, and assessment, the Institute for Scientist and Engineer Educators’ (ISEE’s) Professional Development Program (PDP) is intentionally designed to provide opportunities for participants to return in subsequent years to observe (shadow), practice, and train in a variety of roles (e.g., design team leader, discussion group leader, apprentice facilitator, apprentice instructor). Returning participants not only receive instruction to guide them in these roles, but also receive feedback from core team designers and experienced facilitators and instructors while conducting and after performing these roles. Panelists will discuss one or more roles they engaged in as a PDP participant and how these experiences shaped their approaches to learning, teaching, and working with others as part of their professional careers. Topics to be covered will include leadership, facilitating dialogues and group discussions, the process of active listening, and the intentional design of ideas around diversity, equity, and inclusion. 

Abstract The unprecedented medium-resolution (R_λ∼ 1500–3500) near- and mid-infrared (1–18μm) spectrum provided by JWST for the young (140 ± 20 Myr) low-mass (12–20M_Jup) L–T transition (L7) companion VHS 1256 b gives access to a catalog of molecular absorptions. In this study, we present a comprehensive analysis of this data set utilizing a forward-modeling approach applying our Bayesian framework,ForMoSA. We explore five distinct atmospheric models to assess their performance in estimating key atmospheric parameters:T_eff, log(g), [M/H], C/O,γ,f_sed, andR. Our findings reveal that each parameter’s estimate is significantly influenced by factors such as the wavelength range considered and the model chosen for the fit. This is attributed to systematic errors in the models and their challenges in accurately replicating the complex atmospheric structure of VHS 1256 b, notably the complexity of its clouds and dust distribution. To propagate the impact of these systematic uncertainties on our atmospheric property estimates, we introduce innovative fitting methodologies based on independent fits performed on different spectral windows. We finally derived aT_effconsistent with the spectral type of the target, considering its young age, which is confirmed by our estimate of log(g). Despite the exceptional data quality, attaining robust estimates for chemical abundances [M/H] and C/O, often employed as indicators of formation history, remains challenging. Nevertheless, the pioneering case of JWST’s data for VHS 1256 b has paved the way for future acquisitions of substellar spectra that will be systematically analyzed to directly compare the properties of these objects and correct the systematics in the models.