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Speckle Interferometry of 25 Gaia Two-Parameter Potential Binaries
Authors:
Paul McCudden,
Russell Genet,
John Major,
Zachary Hartman,
A. U. Kovic,
Rick Wasson,
Michael-James Ellis,
Lou Jackson,
Bradley Brungardt,
Zaida Weems,
Astrid Wehlitz,
Evan Wille,
Leon Bewersdorff,
Nick Hardy,
Rachel Freed,
David Rowe,
Thomas C. Smith,
Reed Estrada,
Thomas Meneghini,
Reggie Jones,
Tom Mason,
Dwight Collins,
Mark Copper
Abstract:
Gaia two-parameter (G2P) stars have cumulative errors in parallax and proper motion so great that only their mean positions were reported in DR3. One potential cause of these high errors is another star as indicated by two intensity peaks in the scans. Speckle interferometry astrometric measurements of 25 G2P stars with high multi-peak percentages were obtained with the 1.5m telescope at Mt. Wilso…
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Gaia two-parameter (G2P) stars have cumulative errors in parallax and proper motion so great that only their mean positions were reported in DR3. One potential cause of these high errors is another star as indicated by two intensity peaks in the scans. Speckle interferometry astrometric measurements of 25 G2P stars with high multi-peak percentages were obtained with the 1.5m telescope at Mt. Wilson Observatory. Of the 25 observed G2P stars, seven had no reported Gaia companions within 5.0". We found nearby companions for all seven. The 18 other G2P stars had known Gaia companions within 2.0". Of these, 13 had separations that agreed closely with the speckle measurements but with some discrepancy in position angles, three stars did not agree in either separation or position angle and no companion was detected for the remaining two. Although some of these issues may be resolved in DR4 or DR5, others may be inherent limitations of Gaia capabilities that speckle interferometry observations may be able to fill.
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Submitted 5 April, 2026;
originally announced April 2026.
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Dangerous Questions in Astronomy Education
Authors:
Michael Fitzgerald,
Rachel Freed,
Dan Reichart,
Kate Meredith,
Kalee Tock,
Daryl Janzen,
Saeed Salimpour,
Jennifer Lynn Bartlett,
Matthew Beaky,
Art Borja,
Ken Brandt,
Jim Buchholz,
Patricia Craig,
Anthony Crider,
Richard Datwyler,
Marta Dark-McNeese,
Anna DeJong,
Donovan Domingue,
Debbie French,
Oliver Fraser,
Amy L. Glazier,
Enrique Gomez,
Erika Grundstrom,
Nicole Gugliucci,
Kevin Healy
, et al. (41 additional authors not shown)
Abstract:
As astronomy enters an era defined by global telescope networks, petabyte-scale surveys, and powerful computational tools, the longstanding goals of astronomy education, particularly introductory ``ASTRO101'', but equally encompassing both higher and lower level courses, warrant fresh examination. In June 2024, the AstroEdUNC meeting at UNC--Chapel Hill convened 100 astronomers, education research…
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As astronomy enters an era defined by global telescope networks, petabyte-scale surveys, and powerful computational tools, the longstanding goals of astronomy education, particularly introductory ``ASTRO101'', but equally encompassing both higher and lower level courses, warrant fresh examination. In June 2024, the AstroEdUNC meeting at UNC--Chapel Hill convened 100 astronomers, education researchers, and practitioners to synthesise community perspectives on the purpose, content, and delivery of astronomy education. Beginning with historical vignettes, the meeting's deliberations were organised into six interrelated themes: (1) Context, highlighting astronomy's evolution from classical charting to multi-messenger discovery and its role as a connective thread across STEM and the humanities; (2) Content, exploring how curricula can balance essential concepts with authentic investigations and leverage open-source and AI-augmented resources; (3) Skills, arguing that astronomy should foreground scientific literacy, computational fluency, and communication through genuine data-driven inquiry; (4) Engagement, advocating for active-learning strategies, formative assessment, and culturally inclusive narratives; (5) Beyond the Classroom, emphasising scaffolding, universal-design practices, and K--12/community partnerships; and (6) Astronomy Education Research, outlining priority areas for assessing knowledge, attitudes, and long-term outcomes. We provide concrete recommendations for future astronomy education research development, underscoring the need for approaches to education that are authentic while meeting the learning and life goal needs of the students, a vibrant community of practice and robust researcher-practitioner partnerships to ensure that introductory astronomy is pertinent, applicable and inspiring to a broad student population.
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Submitted 2 July, 2025;
originally announced July 2025.
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Automated Speckle Interferometry of Known Binaries
Authors:
Nick Hardy,
Leon Bewersdorff,
David Rowe,
Russell Genet,
Rick Wasson,
James Armstrong,
Scott Dixon,
Mark Harris,
Tom Smith,
Rachel Freed,
Paul McCudden,
S. Stephen Rajkumar Inbanathan,
Marie Davis,
Christopher Giavarini,
Ronald Snyder,
Roger Wholly,
Maaike Calvin,
Sumner Cotton,
Julia Carter,
Mario Terrazas,
Shane Christopher R.,
Arun Kumar A.,
Sithara Naskath H.,
Mariam Ronald Rabin A
Abstract:
Astronomers have been measuring the separations and position angles between the two components of binary stars since William Herschel began his observations in 1781. In 1970, Anton Labeyrie pioneered a method, speckle interferometry, that overcomes the usual resolution limits induced by atmospheric turbulence by taking hundreds or thousands of short exposures and reducing them in Fourier space. Ou…
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Astronomers have been measuring the separations and position angles between the two components of binary stars since William Herschel began his observations in 1781. In 1970, Anton Labeyrie pioneered a method, speckle interferometry, that overcomes the usual resolution limits induced by atmospheric turbulence by taking hundreds or thousands of short exposures and reducing them in Fourier space. Our 2022 automation of speckle interferometry allowed us to use a fully robotic 1.0-meter PlaneWave Instruments telescope, located at the El Sauce Observatory in the Atacama Desert of Chile, to obtain observations of many known binaries with established orbits. The long-term objective of these observations is to establish the precision, accuracy, and limitations of this telescope's automated speckle interferometry measurements. This paper provides an early overview of the Known Binaries Project and provide example results on a small-separation (0.27") binary, WDS 12274-2843 B 228.
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Submitted 27 March, 2023;
originally announced March 2023.
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Development and validation of an astronomy self-efficacy instrument for understanding and doing
Authors:
Rachel Freed,
David McKinnon,
Michael Fitzgerald,
Christina M. Norris
Abstract:
This paper presents a new astronomy self efficacy instrument, composed of two factors, one relating to learning astronomy content, which we call astronomy personal self efficacy, and the other relating to the use of astronomical instrumentation, specifically the use of remote robotic telescopes for data collection. The latter is referred to as the astronomy instrumental self efficacy factor. The i…
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This paper presents a new astronomy self efficacy instrument, composed of two factors, one relating to learning astronomy content, which we call astronomy personal self efficacy, and the other relating to the use of astronomical instrumentation, specifically the use of remote robotic telescopes for data collection. The latter is referred to as the astronomy instrumental self efficacy factor. The instrument has been tested for reliability and construct validity. Reliability testing showed that factor 1 had a Cronbachs alpha of 0.901 and factor 2 had a Cronbachs alpha of 0.937. Construct validity was established by computing one way analyses of variances, with the p value suitably protected, using independent variables peripherally related to the constructs. These analyses demonstrate that both scales possess high construct validity. The development of this astronomy specific instrument is an important step in evaluating self efficacy as a precursor to investigating the construct of science identity in the field of astronomy.
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Submitted 28 April, 2022;
originally announced April 2022.
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Factors Contributing to Attitudinal Gains in Introductory Astronomy Courses
Authors:
Adam S. Trotter,
Daniel E. Reichart,
Aaron P. LaCluyzé,
Rachel Freed
Abstract:
Most students do not enroll in introductory astronomy as part of their major; for many, it is the last science course they will ever take. Thus, it has great potential to shape students' attitudes toward STEM fields for the rest of their life. We therefore argue that it is less important, when assessing the effectiveness of introductory astronomy courses, to explore traditional curricular learning…
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Most students do not enroll in introductory astronomy as part of their major; for many, it is the last science course they will ever take. Thus, it has great potential to shape students' attitudes toward STEM fields for the rest of their life. We therefore argue that it is less important, when assessing the effectiveness of introductory astronomy courses, to explore traditional curricular learning gains than to explore the effects that various course components have on this attitude. We describe the results of our analysis of end-of-semester surveys returned by a total of 749 students in 2014-2015, at 10 institutions that employed at least part of the introductory astronomy lecture and lab curriculum we first implemented at UNC-Chapel Hill in 2009. Surveys were designed to measure each student's attitude, and to probe the correlation of attitude with their utilization of, and satisfaction with, various course components, along with other measures of their academic background and their self-assessed performance in the course. We find that students' attitudes are significantly positively correlated with the grade they expect to receive, and their rating of the course's overall effectiveness. To a lesser degree, we find that students' attitudes are positively correlated with their mathematical background, whether they intend to major or pursue a career in STEM, and their rating of the effectiveness of the instructor. We find that students' attitudes are negatively correlated with the amount of work they perceived the course to involve, and, surprisingly, the size and reputation of their home institution. We also find that, for the subsets of students who were exposed to them, students' attitudes are positively correlated with their perception of the helpfulness of the lecture component of the course, and of telescope-based labs that utilized UNC-CH's Skynet Robotic Telescope Network.
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Submitted 25 October, 2019;
originally announced October 2019.