16 research outputs found

    ExoClock Project III: 450 new exoplanet ephemerides from ground and space observations

    Get PDF
    The ExoClock project has been created with the aim of increasing the efficiency of the Ariel mission. It will achieve this by continuously monitoring and updating the ephemerides of Ariel candidates over an extended period, in order to produce a consistent catalogue of reliable and precise ephemerides. This work presents a homogenous catalogue of updated ephemerides for 450 planets, generated by the integration of \sim18000 data points from multiple sources. These sources include observations from ground-based telescopes (ExoClock network and ETD), mid-time values from the literature and light-curves from space telescopes (Kepler/K2 and TESS). With all the above, we manage to collect observations for half of the post-discovery years (median), with data that have a median uncertainty less than one minute. In comparison with literature, the ephemerides generated by the project are more precise and less biased. More than 40\% of the initial literature ephemerides had to be updated to reach the goals of the project, as they were either of low precision or drifting. Moreover, the integrated approach of the project enables both the monitoring of the majority of the Ariel candidates (95\%), and also the identification of missing data. The dedicated ExoClock network effectively supports this task by contributing additional observations when a gap in the data is identified. These results highlight the need for continuous monitoring to increase the observing coverage of the candidate planets. Finally, the extended observing coverage of planets allows us to detect trends (TTVs - Transit Timing Variations) for a sample of 19 planets. All products, data, and codes used in this work are open and accessible to the wider scientific community.Comment: Recommended for publication to ApJS (reviewer's comments implemented). Main body: 13 pages, total: 77 pages, 7 figures, 7 tables. Data available at http://doi.org/10.17605/OSF.IO/P298

    Narrative inquiry invites professional development: educators claim the creative space of praxis

    Get PDF
    The current educational context, particularly with the passage of the No Child Left Behind Act of 2001, calls for evidence-based measurable student learning outcomes. Increasingly, teachers feel that opportunities for their praxis are closed off to create, adapt, and discern within the act of teaching, leaving them with little felt agency in classrooms. In this paper, we explore how narrative inquiry used as a medium for professional development can create a needed space where teacher agency for praxis is fostered individually and collectively through understanding otherness. We conclude narrative inquiry invites participating educators to claim the creative space of praxis in their classrooms and fosters a culture of professional learning across participants that we see as the formative work necessary within professional development
    corecore