Mixing the Real World, Real Data, and Computer Visualization to Deepen Student Understanding of the Structure of the Universe
Many undergraduate students harbor strong and persistent misconceptions regarding the size, scale, and structure of the universe (e.g., Miller & Brewer 2001, Trumpler 2001). These misconceptions can affect not only student understanding of the geometry of the universe, but also their understanding of how objects in the universe interact and evolve.These misconceptions can be grouped into three general and related categories: 1) distance underestimation ('Stars are far away, like ten times farther away than the Sun is.'); 2) distance compression ('Stars are really far away, all at about the same distance from us.'); and 3) crowding ('The distance between us and the stars is really big, but the distances between stars is smaller.')
Our project is designed to address these misconceptions through a blending of hands-on, discovery-based laboratory experimentation and computer-aided visualization of astronomical phenomena. We are designing a suite of laboratory activities that prompt students first to develop intuition for concepts such as parallax and homologous expansion through exploration of real-world models, and then apply that intuition in the astronomical realm through the use of the pseudo-3D WorldWide Telescope visualization environment. In this way, we help students navigate the spectacularly large jump in scale from the geometry of their everyday environment to the sizes and distances in the universe.
We have identified four scale-focused laboratory activities for development: 1) a lab devoted to the development of an understanding of parallax, how it can be used to determine distances, and the technical limitations of its use in astronomy; 2) a lab focused on the Hubble Law as a consequence of a homologously expanding universe, and its use as a tool for determining distances on extragalactic scales; 3) a lab detailing the measurement of the size and structure of the Milky Way galaxy; and 4) a lab which allows students to replicate the method of spectroscopic parallax to determine the distance to galactic star clusters. Two of these four activities have been developed, while the remaining two are under development.
To evaluate student learning in these lab activities, we have adopted multiple measures of assessment, including qualitative analysis of written student responses both during and after the lab activities. In parallel with our lab development activities, we have also constructed a new concept inventory, The Size, Scale, and Structure Concept Inventory for Astronomy (S3CI), which provides pre- and post-course diagnostic information. We have tested the S3CI on several undergraduate student populations, and revised the instrument based on student responses. The current version (v.3) is being tested at three institutions.
In the development of these laboratory activities, we have intentionally tried to keep total costs low. The WorldWide Telescope software is freely available and installs and runs easily on Windows machines. The equipment requirements for the hands-on portions are also relatively low.
Once the labs are fully tested and shown to be effective, we hope to package them for wide distribution, even among resource-challenged institutions.
The development of the WWT-enhanced lab materials was delayed due to the need to also develop a new concept inventory to test student understanding of size, scale, and structure in the universe. It was originally anticipated that we would use existing astronomy concept inventories, but we determined early on that these lacked sufficient specificity to be useful as tests of the WWT-enhanced materials. We are developing and testing a new concept inventory in tandem with the WWT-enhanced lab materials development.
Nottis, K. E. K., Ladd, N., Goodman, A., & Udomprasert, P. (2014). Development of an Instrument to Assess Size, Scale, and Structure Concepts in Introductory Astronomy. 12th annual Hawaii International Conference on Education. Honolulu, HI.
Katharyn E. K. Nottis, Ned Ladd, Patricia Udomprasert, and Alyssa Goodman (2014). Preliminary Development of an Instrument to Assess Size, Scale, and Structure Concepts in Introductory Astronomy. Northeastern Educational Research Association. Trumbull, CT.
E.F. Ladd, E.C. Gingrich, K.E.K. Nottis, P. Udomprasert, and A.A. Goodman (2015). Combining Real World Experience and WorldWide Telescope Visualization to Build a Better Parallax Lab, in 'Celebrating Science: Putting Education Best Practices to Work,' ASP Conference Series, Volume 500, eds., Greg Schultz, Sanlyn Buxner, Linda Shore, and Jonathan Barnes, Astronomical Society of the Pacific, San Francisco, CA, p. 191.
E. Gingrich, E. Ladd, , K. Nottis, P. Udomprasert, and A. Goodman (2015). The Size, Scale, and Structure Concept Inventory (S3CI) for Astronomy, in 'Celebrating Science: Putting Education Best Practices to Work,' ASP Conference Series, Volume 500 eds., Greg Schultz, Sanlyn Buxner, Linda Shore, and Jonathan Barnes Astronomical Society of the Pacific, San Francisco, CA, p. 269.
Katharyn Nottis, Ned Ladd, Alyssa Goodman, & Patricia Udomprasert (2016). Initial Development of a Concept Inventory to Assess Size, Scale, and Structure in Introductory Astronomy, accepted for publication in the US-China Education Review.