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Visitor StudiesUnderstanding the Universe
How Do Visitors Understand the Universe?
By Mary Dussault

This article originally appeared in the May/June 1999 issue of the ASTC Newsletter.

What causes the phases of the moon? What are the reasons for the seasons? Is Pluto farther than the stars? A growing body of educational research has convincingly shown that many people—adults and children alike—hold inaccurate (but not essential) ideas about basic astronomical concepts. The 1988 video "A Private Universe," produced by educational researchers at the Harvard-Smithsonian Center for Astrophysics, showed powerfully that these misconceptions or "alternative frameworks" can be quite resistant to change even in the face of dogged efforts to teach the correct concept. Fortunately, parallel developments in pedagogical practice and curriculum design have shown that students can successfully unravel their misconceptions and improve their understanding. It is important, first, for creators of educational experiences to be aware of students' alternative ideas, and second, to treat these ideas not as unfortunate errors, but rather as stepping-stones to scientific understanding. Students must be given concrete experiences and opportunities to grapple with their own theories directly by manipulating models and by discussing their ideas with others.

The past decade has seen these insights from the world of formal education increasingly applied to the world of museum research and practice. Exhibition planners now routinely rely on front-end and formative visitor studies to help them listen to the learner, probe for visitors' attitudes, beliefs, and understandings about a topic, and modify or revise their own preconceptions about the expected visitor experience. In the domain of astronomy especially, museums are ideal venues for experiencing concrete and visual models of the world, but what ideas about astronomy do audiences in informal education environments bring with them? Several museums, including Boston's Museum of Science and the Adler Planetarium and Astronomy Museum in Chicago, have used educational research results and their own front-end and formative studies to think more carefully about designing visitor experiences that "start where visitors are" and enhance their learning and enjoyment of astronomy. Still, the process of learning is as difficult for exhibit developers as it is for visitors…and it's an ongoing conversation.

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In 1997 I was part of a team at the Museum of Science developing the exhibition Welcome to the Universe. Since the exhibition was to be in the lobby of the planetarium, we decided that it should offer an introductory exploration of a few key astronomical themes that would likely be part of any planetarium experience. In particular, astronomical size and scale, and the notion of astronomy as a science of recognizing patterns in the sky (including seasons and moon phases), were two exhibit themes that we explored in qualitative interviews with visitors using props to facilitate conversation.

Patterns in the sky: Day and night and reasons for seasons
I was familiar with the Private Universe research on student misconceptions, but wanted to confirm for myself, and my team, the range of visitor ideas about the reasons for seasons. Since we were planning a specific exhibit component addressing the seasons, we also wanted to explore what features of a physical model, and what lines of conversation, were most fruitful for facilitating visitor learning about earth and sun motions. At a table set up with a lamp with a flexible mount and a free-standing earth globe, I invited visitors to use this "earth and sun" to first model day and night, then later to show how they would model the seasons.

As expected from the research, visitors were far more successful at explaining day and night than the seasons. Children as young as eight could typically find where on the globe it was night, and most people spun the globe in order to "make it night" at some location. Indeed this challenge of modeling day and night was particularly good at stimulating conversations between adult-child pairs and ultimately we made it the invitation activity for the final exhibit component.

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The day/night challenge, however, also revealed some common alternative ideas. Echoing the formal research, a small but significant percentage of visitors would move the globe around the lamp to model day and night. Even more intriguing, a number of visitors would actively raise the lamp so that the sun was shining down on the earth from above the Northern Hemisphere. The table was typically set by museum staff so that the lamp and globe were the same height off the table-our assumption had been that visitors would automatically put themselves in the God's-eye perspective of looking down from space at this earth/sun system, but visitors were clearly bringing to this activity their own ideas about "up" and "down" in space.

Due to the inevitable exigencies of time and money, we ultimately decided not to explicitly address ideas of up and down in the exhibit, instead fixing the sun in place and making design choices that made the orientation of the model obvious to most visitors. I tell this story to highlight the constant struggle of an exhibit developer striving to pay attention to the visitor, while at the same time recognizing the limitations of the exhibit medium for facilitating conceptual change. When most visitors attend to our exhibits, there will be no kind interviewer guiding them through alternative ideas.

This struggle was particularly acute as we went on to have visitors use the model to explore seasonal change. Fully half of the initial group of 30 visitors used the model in ways that expressed the popular misconception that seasonal change is caused by changing distance between the earth and sun. Of those that recognized the tilt of the earth had something to do with seasons, only one or two orbited the globe around the "sun" so that the North Pole maintained its orientation. How could we build an interactive seasons exhibit model that didn't end up reinforcing some misconceptions? What became clear in conversations with visitors was that most people have not had experience in manipulating three-dimensional models of the earth and sun, and little things make a big difference in the effectiveness of the model. Continuing conversations with visitors through formative stages of the exhibit's development guided us to choose specific exhibit design and labeling strategies over others-for example, we discovered that by including a small human figure ("Rick on a Stick") with the model, visitors could investigate how their ground's-eye view of the sun is related to their global position during the day and year. These strategies encouraged visitors to make connections between their own observations and ideas about the seasons and this three-dimensional model.

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Size and scale
By necessity, astronomy exhibitions include lots of models: physical models, computer models, visual representations. As is true for any model, the choice of what to represent and what not to represent inevitably ends up misrepresenting some aspect of the phenomenon being modeled. For example, while our Reasons for Seasons exhibit was successful in getting visitors to explore several different features of the earth/sun system, it also tended to reinforce the common misconception that objects in space are relatively close to each other. An understanding of the size and scale of astronomical systems ends up being crucial in developing conceptual mastery of many space science topics, from the earth's place in the solar system, to an appreciation of space science exploration missions, to an understanding of the structure and evolution of the universe.

To address visitors' ideas about astronomical size and scale, several institutions have created or are planning true scale solar system models. Last year, Joslyn Schoemer of the University of Colorado conducted an intriguing front-end survey at the National Air and Space Museum for the Challenger Center's Voyage scale model solar system project. As part of the survey, 257 visitors were asked to think of some things that are found in the "solar system." Schoemer notes that the aim of this question was "to give project team members ideas of how to approach certain topics, areas that visitors commonly consider versus those that are generally overlooked, and a little insight into some common misunderstandings held by visitors." As might be expected, the most common answer was "planets," with 82 percent of visitors giving it as one of their answers. The second most common answer, however, was "stars" (40.9 percent), which do not belong to the solar system; and galaxies also were named by 17.9 percent of visitors. Schoemer speculates that in addition to misconceptions about relative distances of stars and planets, this result may also indicate that some visitors do not specifically associate the term "solar system" with the sun and its family of planets, but rather with a more general notion of "things astronomical," which includes stars, galaxies, and even the universe. Interestingly, very few visitors (5 percent) mentioned the Earth as a member of the solar system, leading Schoemer to recommend that the project team look for "opportunities…to help visitors realize their own residency in the solar system."

Another question on the survey asked visitors to arrange cards with these words-Moon, Sun, Saturn, Pluto, "farthest humans have gone," and "farthest robotic (unmanned) spacecraft have gone"—in order of distance from Earth. Schoemer discovered another interesting finding: "Visitors are very used to thinking of distances in the solar system in terms of order from the Sun. Even after listening to the request, visitors would frequently place the Sun on one side of the supplied Earth card and Saturn on the other." She quips, "we spent hundreds of years getting away from a geocentric universe to a heliocentric one, and now we can't get the earthbound perspective back!"

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Picturing the universe in The Windy City
Several of the findings of this study are echoed in some open-ended interactive interviews conducted by staff at the Adler Planetarium and Astronomy Museum, Chicago, Ill., as they were planning for several new galleries in their recently-opened building. Evaluators Shauna Keane-Timberlake and Britt Raphling engaged visitors in some picture sorting activities in which visitors were given labeled color laser-prints of celestial objects. In one study, visitors were asked to arrange the pictures on a large sheet of butcher paper to create a picture of the universe. A follow-up, slightly more directed study asked visitors to sort the pictures into four realms which planners wanted to use as a framework to help visitors develop a mental map of the universe's scale and structure: Near Earth, Solar System, Milky Way, and Rest of Universe. Keane-Timberlake and Raphling found that "Exhibit planners knew how astronomers pictured the universe, but did not have any information on what a visitor's picture would look like."

Keane-Timberlake and Raphling include the following points in their summaries of these front-end data: (1) In picturing the universe, most people spontaneously created an "Earth stuff" category, some created a "solar system" or "planets" category, but almost none created either a "Milky Way" or "universe" category. (2) Many adults created a "solar system" category. No children created such a grouping, although many created a "planets" category; apparently, as hinted at in Joslyn Schoemer's study, it is common to learn about the planets without reference to what makes them part of a "system." (3) Visitors don't know as much about astronomical items in the realms furthest from Earth, nor do they have as much confidence in their knowledge of those faraway realms. (4) People conceive of the universe in terms of what's closer and what's farther away, and less familiar things are assumed to be farther away. (5) Some evidence suggests the belief that stars are sprinkled throughout the universe, including within the solar system. These results show that the scientist's view of the hierarchical structure of the cosmos—a concept important to understanding the principles on which the universe as a whole operates—is not second nature to museum visitors.

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Ordering space and time
As part of preliminary planning for a proposed traveling exhibition on cosmology, I recently returned to the Welcome to the Universe exhibition to begin a series of exploratory studies with visitors using an image sorting approach similar to Adler's. I wanted to probe further into visitors' ideas of how the universe is ordered, not only in space but also in time. Visitors were given a collection of seven images of objects in space: Sun, Moon, Hubble Space Telescope, Pleiades star cluster, Saturn, a spiral galaxy, the Hubble deep field galaxies. They were asked to physically order the images in a line, arranging them first in order of actual size of object pictured; then in order of distance from Earth; and finally in order of age, from the most recently formed to the most ancient.

Preliminary results confirm some of the common misconceptions highlighted in other studies: stars and galaxies are often placed in the solar system, or their location is guessed at; a significant minority of survey takers believe that the space telescope is beyond the moon rather than in low earth orbit; many visitors struggle with the relative distance placement of the sun and Saturn, revealing difficulties with an earth-centered perspective on solar system distances. An encouraging aspect to this activity was that it seemed to automatically generate conversations and questions among visitors. As pairs of visitors grappled with arranging the objects in order of distance, you could hear them articulating their theories:

  • "[Hubble Space Telescope] was launched into space. I don't know how far…before Sun and Saturn."
  • "Sun is closer [than Saturn]."
  • "[Saturn] is in orbit and can't get closer to us than the Sun."
  • "We can't see individual stars in other galaxies, so this [spiral galaxy] must be further [than Pleiades]."
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The third challenge, arranging the images in order of age, was especially intriguing because it calls upon visitors to make explicit their theories about evolution of objects in the universe. The comments visitors made as they did this activity were slightly different from comments made in the first two-there were fewer statements of fact, more questions, and more tentative hypothesis making. Visitors recognized this thought process to be more challenging than the first two activities:

  • "This [Sun vs. Saturn] could be tricky…How did they form?"
  • "Do planets form from parts of the sun or are they things captured?"
  • "How did original gas form?"
  • Well, we don't know if our galaxy is older or younger than these."
  • "Didn't they all form at the same time?"

Most of the visitor studies described here were somewhat small-sample, exploratory interviews, and each opens up new questions about visitors' astronomical understandings. Taken together, however, these studies point to several patterns of strengths and gaps in visitors' mental models of the universe. Many science centers and museums have either just opened or are planning new astronomy or space science-related exhibitions. Will our new-found appreciation of the nuances of visitors' cosmic ideas make us better at creating satisfying and successful exhibit experiences? Perhaps some future summative studies will help us learn more from our visitors, thereby continuing this cosmic conversation.


Raphling, B. and Keane-Timberlake, S. (1997). How "Down to Earth" Is the Universe? Visitor Behavior, 12 (1,2): 17-20

Sadler, P. (1992). The Initial Knowledge State of High School Astronomy Students. Unpublished Dissertation, Harvard University Graduate School of Education.

Schneps, Sadler, et. al. (1994). Private Universe. Video produced by the Science Media Group, Harvard-Smithsonian Center for Astrophysics.

Schoemer, J. (1999). The Voyage Front-End Survey. Unpublished working report, Challenger Center for Space Science Education.

Mary Dussault is projects manager for the Universe! Education Forum, sponsored by NASA and managed by the Harvard-Smithsonian Center for Astrophysics.

©1999 Association of Science-Technology Centers Incorporated. All rights reserved.

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