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Abstract We present panchromatic optical + near-infrared (NIR) + mid-infrared (MIR) observations of the intermediate-luminosity Type Iax supernova (SN Iax) 2024pxl and the extremely low-luminosity SN Iax 2024vjm. JWST observations provide unprecedented MIR spectroscopy of SN Iax, spanning from +11 to +42 day past maximum light. We detect forbidden emission lines in the MIR at these early times while the optical and NIR are dominated by permitted lines with an absorption component. Panchromatic spectra at early times can thus simultaneously show nebular and photospheric lines, probing both inner and outer layers of the ejecta. We identify spectral lines not seen before in SN Iax, including [Mgii] 4.76μm, [Mgii] 9.71μm, [Neii] 12.81μm, and isolated Oi2.76μm that traces unburned material. Forbidden emission lines of all species are centrally peaked with similar kinematic distributions, indicating that the ejecta are well mixed in both SN 2024pxl and SN 2024vjm, a hallmark of pure deflagration explosion models. Radiative transfer modeling of SN 2024pxl shows good agreement with a weak deflagration of a near-Chandrasekhar-mass white dwarf, but additional IR flux is needed to match the observations, potentially attributable to a surviving remnant. Similarly, we find SN 2024vjm is also best explained by a weak deflagration model, despite the large difference in luminosity between the two supernovae. Future modeling should push to even weaker explosions and include the contribution of a bound remnant. Our observations demonstrate the diagnostic power of panchromatic spectroscopy for unveiling explosion physics in thermonuclear supernovae. 

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Classification is a general tool of science; it is used to sort and categorize biological organisms, chemical elements, astronomical objects, and many other things. In scientific classification, taxonomy often reflects shared physical properties that, in turn, may indicate shared origins and/or evolution. A “hands-on” galaxy-classification activity developed and implemented by Professional Development Program (PDP) participants, for a high-school summer STEM enrichment program, has been adopted for various age groups and venues, from young (K–3) to college students. We detail the basic tools required, outline the general activity, and describe the modifications to the activity based on learners’ ages and learning objectives. We describe the facilitation strategies learned through PDP training and used when implementing the activity, including prompts to motivate the students. We also discuss how we connected the classification process to astronomy and science more broadly during the concluding remarks. 

It seems intuitive that effective learning experiences in science, technology, engineering and mathematics (STEM) should be inclusive and should mirror authentic STEM as practiced by professionals. However, it is less intuitive what an authentic, inclusive STEM learning experience (AISLE) should look like or include. Over the course of 20 years, the Institute for Scientist & Engineer Educators (ISEE) has grappled with this question, developing and refining a framework of six key elements of authentic and inclusive STEM learning experiences. Here, we present this framework, which grew from an exploration of what “scientific inquiry” means in the context of teaching and learning, and expanded to include practices and norms that are valued in engineering fields. ISEE’s framework is the cornerstone of its Professional Development Program (PDP), which trained early-career science and engineering professionals to teach STEM effectively, primarily at the college level, from 2001-2020. In addition to presenting the six elements of this framework, we describe how PDP participants implemented the elements, and we provide recommendations for putting the elements into practice through the design, teaching and assessment of STEM learning experiences. 

The Professional Development Program (PDP) was a highly impactful and innovative program that was run by the Institute for Scientist & Engineer Educators for twenty years, from 2001–2020. The program trained early-career scientists and engineers to teach effectively and inclusively, while also developing participants’ skills in leadership, collaboration, and teamwork. In this paper, we summarize important aspects of the PDP and some of the program’s major outcomes, describe legacies of the program, and share recommendations based on two decades of experience. A large section of this paper details aspects of the PDP that we consider essential to the program but that might not be apparent from other documentation of the program. Recommendations for others interested in professional development of STEM graduate students and postdoctoral scholars are: 1) invest in establishing program culture; 2) prepare participants pursuing all STEM career paths for inclusive teaching; 3) focus on teaching and learning authentic STEM practices of participants’ fields; 4) provide authentic and challenging contexts for practicing professional skills; 5) model all aspects of what participants are expected to do; and 6) provide opportunities for growth and becoming a collaborator within the community.