Future Reflections Spring/Summer 2004
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Exploring the Universe by Touch
by Bernhard Beck-Winchatz
Editor’s Note: This article began as a simple hand-out resource list of adapted tactile materials and models for the study of astronomy. However, professor Bernhard Beck-Winchatz’s passion for astronomy and his belief in the capacities of blind students would not let him leave it at that. Here is what he has to say to parents:
As a parent of a blind child, it may seem to you that astronomy doesn’t have much to do with the challenges your son or daughter encounters in everyday life. You may wonder whether it isn’t better to spend valuable study time at school and at home on reading, writing, math, and computer skills. In fact, even my own students at DePaul University (who are usually not blind) sometimes ask me why they should care about astronomy. At a time when the economy is not doing well and the job market is tight, many of them are focused on acquiring skills that are valued by their future employers.
There is no doubt that these are valid concerns. As a parent, it is one of your most important responsibilities to help your child develop a solid foundation in basic academic skills that enable him or her to lead a successful life. What you may not realize is that astronomy is ideally suited for this purpose. The nature of astronomy is interdisciplinary, and connections to other areas of the curriculum are easy to make. For example, children can improve their Braille skills when they read about the stars and the planets. They can learn computer skills and how to navigate the Internet when they look for information about the latest NASA missions. They develop language and communication skills when they talk with their friends, teachers, and parents about space exploration. Many children and teenagers think that space is “cool”, so they are motivated to learn. Astronomy can also help boost their confidence. When they realize that they are smart enough, for example, to understand how stars form, the rest of their schoolwork may not seem as daunting to them.
Astronomy is more than a fascinating context for learning basic academic skills. It may seem to you that the distant stars, planets, and galaxies don’t affect our daily lives. But our culture, history, and even our very existence itself are closely connected to the universe. We are not just its observers; we are part of it in a very real sense. When we explore the planets, stars, and galaxies, we learn about who we are. We need to make sure that every single person can be part of this exploration. There are not yet enough Braille astronomy materials for blind children available, but those that do exist cover some of the most fascinating chapters of the story of the universe. In the following I would like to give you a taste of some of these chapters, and, most importantly, tell you about existing educational materials that blind children can use to learn more.
Astronomy Throughout Human History
Constellations like the Big Dipper, Cassiopeia, and Orion are groups of stars that are close to each other in the night sky because they are located in the same direction in space. They inspired the imagination of our ancestors long before they even knew what stars were. The Egyptians, ancient Greeks, and Native Americans each had their own interpretation of the stars’ mystical significance. Constellations also had very practical uses. For example, the Big Dipper, which got its name because it looks like a long-handled ladle seen from the side, played an important role in planning escape routes for 19th century slaves. Members of the Underground Railroad, a loosely organized network of people who helped slaves escape to the North, taught the slaves specific escape routes through coded songs that were passed on from plantation to plantation. One of these songs, entitled “Follow the Drinking Gourd”, describes an escape route from Alabama and Mississippi based on the position of the Drinking Gourd, which is the name the slaves used for the Big Dipper.
Noreen Grice’s book Touch the Stars II contains a tactile image of the Big Dipper, including an explanation in Braille and large print of how it can be used to find the North Star. The book also contains tactile images of other constellations and some of the legends that surround them. David Hurd and John Matelock at Edinboro University of Pennsylvania have developed a large tactile chart that shows the part of the sky visible from mid-northern latitudes, including the Big Dipper, the North Star, and other major constellations. The chart comes with explanations and a detailed legend in Braille. A smaller version, showing only the so-called circumpolar constellations, is also available. (Information on how to obtain Touch the Stars II, the Edinboro University charts, and all other resources discussed below can be found at the end of this article.)
Another example of the practical importance of astronomy for our ancestors is the use of celestial events to measure the passage of time. Humans invented calendars because they needed to know when to plant and harvest their crops, and when to prepare for the cold winter season. Some of the earliest calendars were based on the orbit of the Moon. As the Moon revolves around Earth, it goes through a cycle of phases, e.g., New Moon, Waxing Crescent, First Quarter, etc. In a lunar calendar a month is defined as the time it takes for the Moon to complete one full cycle of phases—about 29.5 days. To this day the Chinese, Hebrew, and Islamic calendars are based on the lunar cycle. The phases of the Moon are an important topic in the middle school science curriculum. Many children have misconceptions about what causes them. For example, some think they are caused by Earth’s shadow, while others attribute them to clouds. Touch the Stars II contains a wonderful illustrated explanation of the lunar cycle that can help address these misconceptions.
The use of constellations by slaves to plan escape routes and lunar calendars are two examples of the practical importance of astronomy throughout history. But there is another less practical but equally fascinating connection between the cosmos and our lives: Humans are not just observers of the distant universe, they are a part of it. Every atom in our bodies is as old as the universe itself. The hydrogen atoms in water molecules, which make up about 70 percent of our bodies, were created in the Big Bang itself 13.7 billion years ago. The calcium in our bones, the carbon in our cells, and the iron in our blood were formed in nuclear fusion reactions from hydrogen in stars that died billions of years ago. At the end of their lives these stars released gases that contained these newly formed atoms back into space, allowing a new generation of stars to form, including our Sun and its planets. Another five billion years from now the Sun too will end its life and return some of its gases back into space. Perhaps in the distant future the very atoms that presently make up your body will again become part of a life form on a planet that orbits a star that is yet to be formed.
Noreen Grice’s book Touch the Universe contains tactile pictures taken by the Hubble Space Telescope and text in Braille and large print that represent many of the stages of the life cycle of stars. The Eagle Nebula is an example of a stellar nursery, where stars and planets are being formed from the gases left behind by previous generations of stars. The Ring, Hourglass, and Eskimo Nebulae are examples of Sun-like stars that have reached the end of their lives. Stars that are much more massive than the Sun end their lives in a supernova explosion. Eta Carina is an example of such a star.
Life on Earth and Elsewhere
Astronomical events, such as the Big Bang and the life cycles of stars provided the building blocks for life. But even the emergence and evolution of life on Earth itself is closely tied to astronomy. For the first few hundred million years after its formation, 4.5 billion years ago, conditions on Earth were not suitable for life. Large meteorites left over from the formation of the solar system constantly bombarded our planet. Only after this heavy bombardment stopped was life able to emerge. Though less frequent, large meteorite impacts continued to play a preeminent role. Mass extinctions caused by impacts of large meteorites frequently killed the dominant species, making room for new species to take over. An example of such an event was the extinction of the dinosaurs 65 million years ago at the end of the Cretaceous period, which allowed mammals, and eventually humans, to flourish. Few impact craters exist on the surface of Earth because they are obliterated after a relatively short period of time by plate tectonics and atmospheric erosion. In contrast, many ancient craters have survived on the Moon, which has neither plate tectonics nor an atmosphere.
A tactile map of the surface of the Moon developed at Edinboro University of Pennsylvania shows lunar impact craters and other geological features. The lunar highlands are the most heavily cratered, indicating that they are the Moon’s oldest landform. The maria are relatively smooth regions filled with solidified lava. They were formed much later than the highlands, so there has not been time for many craters to form.
An impact by a large meteorite on Earth could have catastrophic consequences. Near-Earth asteroids pose the greatest threat, because they can get very close to Earth in their orbit around the Sun. There are a thousand of them as large as a kilometer, about a hundred thousand as large as a football field, and many millions as large as a house. Fortunately, none of the known asteroids is likely to impact Earth in the near future. However, many have not even been discovered yet, and scientists are continually searching the sky for objects that may threaten our planet in the future. They also study their physical properties, such as their shapes and compositions, so that we can develop the means for deflecting a potential impactor before it can cause any damage. Their research also provides information that may someday allow us to send robots or even humans to asteroids and mine them for valuable minerals.
NASA’s Jet Propulsion Laboratory and Cornell University have developed scientifically accurate three-dimensional scale models of asteroids based on radar observations. To create these models scientists transmit radar waves toward the asteroids and process the echoes into three-dimensional computer models. Real models are then fabricated using a technique called rapid prototyping. It is interesting to note that this method parallels the process by which blind people form mental images of three-dimensional objects: instead of detecting the light emitted by these objects with their eyes, they analyze the tactile feedback from the surface of the object to their hands. Similarly, radar astronomers analyze the feedback from the surfaces of the asteroids via radar waves sent and felt by their radio telescopes.
Astronomy helps us to understand where we come from and where we are going, but it also holds the answer to another fundamental question humans have asked for thousands of years: “Are we alone in the universe?” So far no hard evidence for life outside of Earth has been found, but the search is on, and blind astronomer Dr. Kent Cullers is one of its leaders. Dr. Cullers, who inspired the character of Dr. Kent Clark in the movie Contact, is the Director of Research and Development at the SETI Institute, whose mission it is to “explore, understand, and explain the origin, nature and prevalence of life in the universe.” NASA is searching for clues for primitive extraterrestrial life in places like Mars, Jupiter’s moon Europa, and Saturn’s moon Titan. Titan is particularly interesting because its thick atmosphere contains methane and nitrogen gas. The conditions on Titan may be similar to those on Earth shortly after its formation. The Cassini spacecraft is currently on its way to Saturn and will arrive in July of 2004. Once there,
Cassini will release the space probe Huygens, which will land on the surface of Titan in early 2005. Because of the harsh environment it is unlikely that life currently exists on Titan, but scientists hope to gain important insights into how life began on our own planet.
David Hurd and John Matelock have created a tactile diagram of the Cassini spacecraft, which shows the orbiter, the Huygens probe and Saturn itself. They have also produced an entire book of tactile images of the planets and other celestial objects entitled Our Place in Space: A Tactile Exploration with Braille. Tactile images of Saturn can also be found in Touch the Universe, Touch the Stars, and on a scale map of the solar system available from the Southeast Regional Clearinghouse in Charleston, South Carolina.
Astronomy provides a rich and exciting context for learning across many disciplines. It can help children improve their Braille, math, and computer skills, and teach them about history and societal issues. At the same time it can give them a sense of their place in the cosmos by addressing questions humans have asked for thousands of years: “Where do we come from?” “Where are we going?” and “Are we alone in the universe?” Clearly, there is a need for more educational materials for blind children in astronomy. Several are already under development by NASA-funded groups. But you and your child do not have to wait for them: even the materials that already exist cover some of the most fascinating chapters of the story of the universe. Happy exploring!
Touch the Universe: A NASA Braille Book of Astronomy, by Noreen Grice. ($35.00). Available online at <www.nap.edu/ catalog/10307.html>, by phone: (888) 624-8373), by fax: (202) 334-2451, or by mail: National Academies Press, 500 Fifth Street NW, Lockbox 285, Washington, DC 20055. A limited number of these books are also available at a discount from the National Federation of the Blind Materials Center. For more information call (410) 659-9314 or look online at <www.nfb.org>.
Touch the Stars II, by Noreen Grice. ($30.00). Available by phone: (800) 548-7323, by fax: (617) 437-0456, by email: <[email protected]>, or by mail: National Braille Press, 88 St. Stephen Street, Boston, Massachusetts 02115.
Our Place in Space: A Tactile Exploration with Braille, developed by the Edinboro University of Pennsylvania Planetarium and Tactile Lab. ($40.00), Available from the Edinboro University Planetarium: (814) 732-2493.
Asteroid Scale Models, available from Design Cast Studios by phone: (270) 869-8477 and online at: <www.dcstudios.com/ ast_models.html> ($10.00). The Space Exploration Experience (SEE) Project is currently developing a set of activities based on these scale models, which are (or will be) available online at http://analyzer.depaul.edu/SEE_Project/>. Diagrams of the asteroid orbits have already been designed for use with thermal expansion machines (PIAF, TIE, etc.). An article describing the asteroid models and some of the activities can be found at http://aer.noao.edu/AERArticle.php?issue=4§ion=3&article=1>.
Tactile Solar System Map, with Relative Planet Sizes and Distance from the Sun, available from the Southeast Regional Clearinghouse by phone: (843) 953-5437, email: <[email protected]>, or mail: Kathryn Guimond, College of Charleston, Lowcountry Hall of Science & Math, 66 George Street, Charleston, South Carolina 29424.
The following four tactile charts and maps are available from the Edinboro University of Pennsylvania Planetarium by phone at (814) 732-2493.
Tactile Full Sky Chart, showing all constellations visible from mid-northern latitudes ($18.00)
Tactile Circumpolar Constellation Chart ($3.00)
Tactile Map of the Moon ($3.00)
Tactile Map of the Cassini Spacecraft ($3.00)
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