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We present and confirm TOI-1751 b, a transiting sub-Neptune orbiting a slightly evolved, solar-type, metal-poor star (T_eff= 5996 ± 110 K,$\log (g)=4.2\pm 0.1$,V= 9.3 mag, [Fe/H] = −0.40 ± 0.06 dex) every 37.47 days. We use TESS photometry to measure a planet radius of${2.77}_{-0.07}^{+0.15}{R}_{\oplus }$. We also use both Keck/HIRES and APF/Levy radial velocities (RV) to derive a planet mass of${14.5}_{-3.14}^{+3.15}{M}_{\oplus }$, and thus a planet density of 3.6 ± 0.9 g cm⁻³. There is also a long-period (∼400 days) signal that is observed in only the Keck/HIRES data. We conclude that this long-period signal is not planetary in nature and is likely due to the window function of the Keck/HIRES observations. This highlights the role of complementary observations from multiple observatories to identify and exclude aliases in RV data. Finally, we investigate the potential compositions of this planet, including rocky and water-rich solutions, as well as theoretical irradiated ocean models. TOI-1751 b is a warm sub-Neptune with an equilibrium temperature of ∼820 K. As TOI-1751 is a metal-poor star, TOI-1751 b may have formed in a water-enriched formation environment. We thus favor a volatile-rich interior composition for this planet.

 

The extreme environments of ultra-short-period planets (USPs) make excellent laboratories to study how exoplanets obtain, lose, retain, and/or regain gaseous atmospheres. We present the confirmation and characterization of the USP TOI-1347 b, a 1.8 ± 0.1R_⊕planet on a 0.85 day orbit that was detected with photometry from the TESS mission. We measured radial velocities of the TOI-1347 system using Keck/HIRES and HARPS-N and found the USP to be unusually massive at 11.1 ± 1.2M_⊕. The measured mass and radius of TOI-1347 b imply an Earth-like bulk composition. A thin H/He envelope (>0.01% by mass) can be ruled out at high confidence. The system is between 1 and 1.8 Gyr old; therefore, intensive photoevaporation should have concluded. We detected a tentative phase-curve variation (3σ) and a secondary eclipse (2σ) in TESS photometry, which, if confirmed, could indicate the presence of a high-mean-molecular-weight atmosphere. We recommend additional optical and infrared observations to confirm the presence of an atmosphere and investigate its composition.

 

We present a radial velocity (RV) analysis of TOI-1136, a bright Transiting Exoplanet Survey Satellite (TESS) system with six confirmed transiting planets, and a seventh single-transiting planet candidate. All planets in the system are amenable to transmission spectroscopy, making TOI-1136 one of the best targets for intra-system comparison of exoplanet atmospheres. TOI-1136 is young (∼700 Myr), and the system exhibits transit timing variations (TTVs). The youth of the system contributes to high stellar variability on the order of 50 m s⁻¹, much larger than the likely RV amplitude of any of the transiting exoplanets. Utilizing 359 High Resolution Echelle Spectrometer and Automated Planet Finder RVs collected as part of the TESS-Keck Survey, and 51 High-Accuracy Radial velocity Planetary Searcher North RVs, we experiment with a joint TTV-RV fit. With seven possible transiting planets, TTVs, more than 400 RVs, and a stellar activity model, we posit that we may be presenting the most complex mass recovery of an exoplanet system in the literature to date. By combining TTVs and RVs, we minimized Gaussian process overfitting and retrieved new masses for this system: (m_b−g=${3.50}_{-0.7}^{+0.8}$,${6.32}_{-1.3}^{+1.1}$,${8.35}_{-1.6}^{+1.8}$,${6.07}_{-1.01}^{+1.09}$,${9.7}_{-3.7}^{+3.9}$,${5.6}_{-3.2}^{+4.1}$M_⊕). We are unable to significantly detect the mass of the seventh planet candidate in the RVs, but we are able to loosely constrain a possible orbital period near 80 days. Future TESS observations might confirm the existence of a seventh planet in the system, better constrain the masses and orbital properties of the known exoplanets, and generally shine light on this scientifically interesting system.

 

The Mechanical Engineering Department at a private, mid-sized university was awarded the National Science Foundation (NSF) Revolutionizing Engineering and Computer Science Departments (RED) grant in July 2017 to support the development of a program that fosters students’ engineering identities in a culture of doing engineering with industry engineers. The Department is cultivating this culture of “engineering with engineers” through a strong connection to industry, and through changes in the four essential areas of, a shared department vision, faculty, curriculum and supportive policies. This paper reports our continued efforts in these four areas and our measurement of their impact. Shared department vision: During the first year of the project, the department worked together to revise its mission to reflect the goal of fostering engineering identity. From this shared vision, the department aims to build a culture to promote inclusive practices. In the past year during the COVID-19 pandemic, this shared vision continued to guide many acts of care and community building for the department. Faculty: The pandemic prompted faculty to reflect on how they delivered their courses and cared for students. To promote inclusive practice, faculty utilized recorded lectures, online collaboration tools and instant messaging apps to provide multiple ways of communication for students. Although faculty summer immersion had to be postponed due to pandemic, interactions with industry continued in design courses, and via virtual seminars and socials. Efforts were also extended to strengthen connections between the department and recent graduates who just began working in industry and could become mentors for current students. Curriculum: A new curriculum to support the goals of this project was rolled out in the 2019-20 academic year. The pandemic hit right in the middle of the initial implementation of this new curriculum. Therefore, to maintain the essence of the new curriculum that emphasizes hands-on, doing engineering and experiential learning in the remote setting, many adjustments and modifications were made. Although initial evidence indicates the effectiveness of the new courses/curriculum even under remote teaching and learning, there are also many lessons-learned that can be examined for future implementations and modifications of the curriculum. Supportive policies: The department agreed to celebrate various acts of care for students and cares for teaching and learning in Annual Performance Reviews. Faculty also worked with other departments, the college, and the university to develop supportive policies beyond the department. For example, based on the recommendation from the department, the college set up a Student Advocate role who would assist students navigate through any incident that make they feel excluded. The new university tenure and promotion guidelines have just been approved with the support from the faculty in the department. Additionally, the department’s effort of building an inclusive culture is aligned with the university initiative for a reform to emphasize anti-racism curriculum. Details of the action items in each area of change that the department has taken to build this inclusive culture to foster engineering identity are shared in this paper. In addition, research gauging the impact of our efforts are discussed. This project was funded by the Division of Undergraduate Education (DUE) IUSE/PFE: RED grant through NSF. 

Background. While educational change often involves bold talk about disruptive ideas that eventually need to be institutionalized, a critical but often less visible element of sustaining change is work such as maintaining a shared vision, onboarding new people, negotiating small issues in light of department culture, and coordinating big changes with existing efforts. While knowledge about these forms of invisible work exist in other disciplines, these issues seem understudied in engineering education. This work approaches this issue of invisible knowledge with a design orientation, and specifically draws on the field of design-based research. Increasingly, design is recognized as a knowledge producing activity, resulting in insights into generative ways of defining problems, frameworks for generating solutions to problems, examples of what it looks like to connect theory to specific problems. Purpose: As a design effort, this work asks: How might a specific department create a sustainable practice to support the invisible work of coordinating and sustaining change? As a scholarly effort, this instance of design can result in a culminating problem definition, a solution framework, and examples of theory use that represent knowledge contributions. Approach: A mechanical engineering department in a small, private educational institution worked for four months to develop a sustainable practice to support invisible work of coordinating and sustaining change. Following an initial commitment of 60 minutes once every three weeks and 3-hour retreat to explore possibilities, the department then iteratively designed and then carried out sample conversations. Each iteration involved specifying the goals of the conversation, how to have the conversation (the design) and the rationale for connecting the design to the goals. Traces from the process represent the data for this work. Results. Over time, the conversations came to be designed along four dimensions: topic, time allocation, turn-taking, and traces. We have learned that topics that are of immediate relevance to everyone are particularly powerful (initial topics included "being back on campus" and "navigating in-person"). We are currently leveraging a time allocation that devotes the most time to hearing from each participant on the topic, then time for the group to cautiously explore synthesis, and finally time for the group to weigh in on future conversation topics. Approaches to turn-taking have involved decentralization (e.g., each current speaker invites the next speaker) and respect (speakers have a chance to "pass" and then choose the next speaker). Finally, we are experimenting with how to balance the creation of traces as a natural part of the process, such as through real-time transcription in the chat feature of zoom. Undergirding each of these dimensions are connections to the intended goals, connections to relevant theory, and connections to the long-term goal of sustainability. In presenting these ideas, we will focus on how the information being offered connects to the current body of knowledge in engineering education. Conclusion. It is promising to treat the work of department culture as a design problem. The ideas in this framework may serve as inspiration to others seeking to create their own sustainable mechanisms but with different conditions. During the winter and spring of 2022, the approach will be additionally tested via six deployments, and insights will be shared in subsequent publications. 

This is a Lessons-Learned paper. During the past years the Mechanical Engineering program at XXXX has made numerous curricular changes that focus on cultivating a culture of “engineering with engineers” and developing strong engineering identities in their students. The four major changes in the curriculum include implementing an integrated electrical engineering and data acquisition (DAQ) course sequence, adding a vertically integrated design projects (VIDP) course sequence, modifying an existing design sequence, and adding real engineering into existing courses. Many of these changes rely on hands-on labs and on creating connections between students and industry. In the spring of 2020, the pandemic forced the program to offer all of its courses online and challenged the department to rethink how it could continue its strong hands-on, industry-focused program. Most courses were quickly flipped and online class time via Zoom focused on community building and small group discussions. New checks and activities helped to keep students engaged and provided regular feedback to instructors on student progress. Lab assignments were modified so that all lab work could be done remotely. This paper details these changes, describes successes and failures, and discusses lessons learned. A summary of the paper will be presented as a lightning-talk during the 2021 ASEE Annual Conference. 

The Mechanical Engineering Department at a private, mid-sized university was awarded the National Science Foundation (NSF) Revolutionizing Engineering and Computer Science Departments (RED) grant in July 2017 to supports the development of a program that fosters students’ engineering identities in a culture of doing engineering with industry engineers. With a theme of strong connection to industry, through changes in four essential areas, a shared department vision, faculty, curriculum, and supportive policies, this culture of “engineering with engineers” is being cultivated. Many actions have taken to develop this culture. This paper reports our continued efforts in changes of these four areas: Shared department vision: The department worked together to revise the department mission to reflect the goal of fostering engineering identity. From this shared vision, the department updated the advising procedure and began addressing the challenge of diversity and inclusion faced in engineering. A diversity and inclusion statement was discussed by all faculty and included in all syllabi offered by the department to emphasize the importance of an inclusive culture. Faculty: The pandemic prompted faculty to think differently on how they deliver their courses and interact with students. Many faculty members adapted inverted classroom pedagogy and implemented remote laboratories to continue the emphasis of “doing engineering”. The industry adviser holds weekly virtual office hours to continue to provide industry contacts for students. Although faculty summer immersion this past year was postponed due to pandemic, interactions with industry were continued in various courses. Curriculum: A new mechanical engineering curriculum rolled out in the 2019-20 academic year. Although changes have to be made due to the pandemic but the focus of “engineering with engineers” remained. An example would be the Vertical Integrated Design Projects (VIDP) courses offered in Spring 2020. Utilizing virtual communication tools such as Microsoft Teams, student teams in the VIDP courses could still interact with industry advisors on a regular basis and learned from their experiences. Supportive policies: The department has worked closely with other departments, the college and the university to develop supportive policies. Recently, the college recommended the diversity and inclusion statement developed by the department to all senior design courses offered in the college. The university was aware of the goal of this project in fostering students’ engineering identities, which in term can promote the retention of URMs. The department’s effort is aligned with the new initiative the university launched to build an inclusive environment. More details of the action items in each area of change that the department has taken to build this culture of engineering with engineers will be shared in the full-length paper. This project was funded by the Division of Undergraduate Education (DUE) IUSE/PFE: RED grant through NSF. 

WIP: The Mechanical Engineering (ME) Department at Seattle University was awarded a 2017 NSF RED (Revolutionizing Engineering and Computer Science Departments) grant. This award provided the opportunity to create a program where students and faculty are immersed in a culture of doing engineering with practicing engineers that in turn fosters an identity of being an engineer. Of the many strategies implemented to support this goal, one significant curricular change was the creation of a new multi-year design course sequence. This set of three courses, the integrated design project (IDP) sequence, creates an annual curricular-driven opportunity for students to interact with each other and professional engineers in the context of an open-ended design project. These three courses are offered to all departmental first-, second-, and third-year students simultaneously during the spring quarter each year. Each course consists of design-focused classroom instruction tailored to that class year, and a term design project that is completed by teams of students drawn from all three class years. This structure provides students with regular design education, while also creating a curricular space for students across the department to interact with and learn from one of another in a meaningful way. This structure not only prepares students for their senior design experience, but also builds a sense of community and belonging in the department. Furthermore, to support the "engineering with engineers" vision, volunteer engineers from industry participate as consultants in the design project activities, giving students the opportunity to learn from professionals regularly throughout their entire four years in the program. This course sequence was offered for the first time in 2020, and while the global pandemic impacted the experience, the initial offering was by all accounts a success. This paper provides an overview of the motivation for the three IDP courses, their format, objectives, and specific implementation details, and a discussion of some of the lessons learned. These particulars provide other engineering departments with a roadmap for how to implement this type of a curricular experience in their own programs. 

With JWST’s successful deployment and unexpectedly high fuel reserves, measuring the masses of sub-Neptunes transiting bright, nearby stars will soon become the bottleneck for characterizing the atmospheres of small exoplanets via transmission spectroscopy. Using a carefully curated target list and observations from more than 2 yr of APF-Levy and Keck-HIRES Doppler monitoring, the TESS-Keck Survey is working toward alleviating this pressure. Here we present mass measurements for 11 transiting planets in eight systems that are particularly suited to atmospheric follow-up with JWST. We also report the discovery and confirmation of a temperate super-Jovian-mass planet on a moderately eccentric orbit. The sample of eight host stars, which includes one subgiant, spans early-K to late-F spectral types (T_eff= 5200–6200 K). We homogeneously derive planet parameters using a joint photometry and radial velocity modeling framework, discuss the planets’ possible bulk compositions, and comment on their prospects for atmospheric characterization.