Udomprasert P, Goodman A, Ladd E, Offner S, Houghton H, Johnson E, Sunbury S, Plummer JD, Wright E, Sadler P, et al.WorldWide Telescope in Education. In: Impey C, Buxner S Astronomy Education - A Practitioner’s Guide to the Research. Bristol, UK: IOP Publishing. ; In Press.
Most students have an intuitive understanding of how to gauge the distances to objects in their local environment. Through a combination of binocular vision and visual cues such as the perceived sizes of known objects, students can construct a three-dimensional mental model of their local surroundings, and use it to make sense of their environment.
They do not typically understand, however, that the same geometric principles behind binocular vision and depth perception are also used for quantitative distance determination by triangulation and astronomical parallax. We have built a hybrid exercise combining experiential learning with computer visualization for undergraduate students to explore distance determination in the local terrestrial and astronomical contexts in an effort to help them bridge their intuitive understanding to geometries where distance measurement is not possible visually, but is possible via more precise measurements made with instrumentation.
Students explore distance determination in an outdoor setting where the distances to objects (~50m) are too large for intuitive distance measurement, but can be determined quantitatively through a simple triangulation process. By measuring the direction to a target object from two different positions separated by a known distance, they can determine the distance to the target. This triangulation method is used by moving ships at sea, to determine the distance to, say, a visible lighthouse. It is also the method by whichastronomers measure the distance to nearby stars (In this case, the “moving ship” is the Earth in its orbitabout the Sun.).
The second component of the activity involves using the multi-perspective visualization capability of the WorldWide Telescope (WWT) virtual environment. WWT, originally developed by Microsoft Research, and now managed by the American Astronomical Society, is freely available to the world community. WWT represents real astronomical data in a three-dimensional environment that students can investigate from a variety of physical perspectives. With this software, students can compare the apparent locations of nearby stars from widely separated vantage points (much larger than the size of the Earth’s orbit),making the shifts in star positions due to the parallax effect obvious. They can see how their view of universe changes as they change their observing location, connecting their intuitive understanding of distance measurement, and their experience with terrestrial triangulation, to the astronomical realm.
Assessment data indicate that, after participating in this hybrid activity, students better connect their intuitive understanding of distance determination to the quantitative calculations required for precise measurement of distance.
When teaching science topics in which objects are too large or too small to observe laboratory settings—as is the case for astrophysics—how do you convey complex and intangible relationships in a meaningful way? Studies have shown that interactive visualization models that address common misconceptions can be powerful learning experiences. This article examines how the WorldWide Telescope (WWT) Ambassadors program has utilized the dynamic environment of the WWT platform to build meaningful representations of complex topics, and effectively address these teaching needs.
We develop three-dimensional mental models of our physical environs from two dimensional imagery we collect with our eyes. This is possible only because we move through that environment, viewing it from multiple perspectives, and construct a model consistent with a collection of two-dimensional views. The technique works well for structures whose sizes are comparable to the magnitude of our movements, such as rooms, buildings, and even cities; but for much larger structures, we are effectively limited to a single perspective, and therefore must create mental models from indirect measures.
The astronomical realm is almost always in this latter category, and student understanding of the structure of the universe is limited by their inability to use multi-perspective techniques to generate an accurate mental image of astronomical structure. Without an accurate model, students tend to underestimate the distances to and between astronomical objects, leading to inaccurate assumptions regarding the overall size of the universe, the interactions between celestial objects, and our location within and among these structures.
To improve student understanding of the size, scale, and structure of our universe, we have developed hybrid laboratory activities based on a mix of hands-on discovery with physical models and multi- perspective visualization using the WorldWide Telescope (WWT) virtual environment. WWT, developed by Microsoft Research, managed and supported by the American Astronomical Society, and freely available to the world community, represents real astronomical data in a three-dimensional environment that students can investigate from a variety of physical perspectives. They can virtually “fly through”astronomical structures and thus use the same techniques they use in their local everyday environment to develop an accurate mental model on an astronomical scale.
These new lab activities connect indirect measurements of distance and structure (based on real astronomical data) to visualizations of those same structures, so that students understand the techniques by which structure is measured, and create accurate mental models of those structures. This not only improves their understanding of their astronomical environs, but also improves their understanding of the physical processes that occur in our universe.
We will present examples of these activities, and assessment data measuring the improvement in student understanding of astronomical size, scale, and structure, as a result of their interactions with these materials.
We present a concept inventory to evaluate student understanding of size, scale, and structure concepts in the astronomical context. Students harbor miscon- ceptions regarding these concepts, and these misconceptions often persist even after instruction. Evaluation of these concepts prior to as well as after instruction can ensure misconceptions are addressed. Currently, no concept inventories focus exclusively on these geometrical ideas, so we have developed the Size, Scale and Structure Concept Inventory (S3CI). In fall 2013, we piloted a 24-item version of the S3CI in an introduc- tory astronomy course at a small private university. We performed an item analysis and estimated the internal consistency reliability for the instrument. Based on these anal- yses, problematic questions were revised for a second version. We discuss the results from the pilot phase and preview our updated test in this work.
A valid and reliable concept inventory has the potential to accurately evaluate undergraduates’ understanding of size, scale, and structure concepts in the astronomical context, as well as assess conceptual change after targeted instruction. Lessons learned in the evaluation of the initial version of the S3CI can guide future development of this and other astronomical concept inventories. Instructors interested in participating in the ongoing development of the S3CI should contact the authors.
Research has shown that undergraduates have problems understanding astronomical concepts, especially size, scale, and structure. One way to evaluate understanding is to use concept inventories. Therefore, the purpose of this study was to begin the development of the Size, Scale, and Structure Concept Inventory (S3CI) to assess understanding of these concepts in introductory undergraduate astronomy courses for majors and non-majors. A secondary purpose was to determine the impact of a newly developed WorldWide Telescope (WWT) enhanced lab on parallax, part of a suite of WWT enriched labs for introductory astronomy courses currently under development. We present in this paper preliminary results from the first WWT-enhanced lab on parallax. In Fall 2013, a beta version of the S3CI was piloted in an introductory astronomy course at a small private university. An item analysis was done and estimates of internal consistency reliability were determined using the Kuder-Richardson Formula #20 (KR20). The impact of the newly developed lab was also evaluated using a sub-test of six questions from the S3CI.
We present a lab activity designed to help students understand the concept of parallax in both astronomical and non-astronomical contexts. In an outdoor setting, students learn the methodology of distance determination via parallax. They identify a distant landmark to establish a reference of direction, and then measure the change in apparent direction for more nearby objects as they change position in a 2 meter radius “orbit” around the “Sun.” This hands-on activity involves large, visually-discernable angles so that students can internalize the concept of parallax from everyday experi- ence. However, students often have difficulty transferring this experience to the astro- nomical realm, so we pair this hands-on activity with a more explicitly astronomically- based activity using the WorldWide Telescope visualization environment. Students ap- ply the same methodology in this environment and learn how the apparent motion of stars is related to their distance from Earth. The combination of hands-on activity and computer-aided visualization is designed to produce a deeper understanding of paral- lax in the astronomical environment, and an improved understanding of the inherently three-dimensional distribution of objects in our universe. More formal assessment is underway.