Training Manual Format s1

Jumbo Big Dipper - 1 of 7 Jumbo Big Dipper

Brief Summary

This demo uses a three-dimensional model of the stars that make up the Big Dipper, in which each star is a light suspended from the ceiling. Visitors can wander amongst the “stars” to see how they look from different locations, and how far away the stars are relative to distances within our solar system.

Equipment Required

Big Dipper cart You will also need: should contain the following:  Laptop with Big Dipper file opened  “Sun” light on the end of a standing  Floor mark indicating pole “Sun” stanchion position  Five signs on stanchions  7 color-coded hooks, already in the ceiling  Plexi “window” with engraved shape of  If possible, a partner Big Dipper

 Seven lights on fishing line, each wound around a colored hanger

 Light hanging pole

 Floor patches for the seven stars

 Digital camera Jumbo Big Dipper - 2 of 7 Main Teaching Points

 Constellations are made up of stars that lie scattered in three-dimensional space, and are not usually connected to each other in any way.  The familiar pattern of a given constellation can only be seen when viewed from near the Sun – those same stars do not appear in that pattern when viewed from anywhere else in the universe.  Stars are a very long way away compared to distances within our solar system.

Educational Strategy

This giant model encourages visitors to have a kinesthetic experience of the three- dimensionality of constellations. Unlike smaller tabletop models, this large scale set up allows visitors to walk through and around the Big Dipper, seeing the stars from different angles. There is no way a visitor could see the Big Dipper this way unless he or she traveled great distances through the universe to gain a similar perspective of the actual stars. (This, of course, is impossible, since travel to even the closest star would take in the range of 10,000 years).

Set Up

 Test all lights before bringing cart out onto floor.  Bring cart out to where ceiling hooks are situated.  Using hanging pole, hang all seven lights on the corresponding hooks (hooks and light hangers are color-coded).  Set up Sun pole.  Set up stanchions in a large circle facing outward, so that images match view of stars  Put each of the floor patches under the corresponding stars.  Open a Big Dipper preset in Starry Night Pro.

Suggested ways of presenting demo

Try this approach, which treats the demo as a guessing game:

1. Exploring the Model  As visitors approach the area, tell them that the lights represent the stars of a well- known star pattern.  Encourage them to walk around and view the “stars” from different locations until they recognize the star pattern.  Having visitors close one eye may help them see the star pattern. 2. Seeing the Big Dipper  When they have recognized it, or when you feel they are ready to stop looking/guessing, encourage them to view the ‘stars’ from the Sun (but don’t tell them it is the Sun). Jumbo Big Dipper - 3 of 7  When they see the shape of the Big Dipper, ask them what this star (the Sun) might be.  Discuss why you can only see the stars as the Big Dipper when you are near the Sun.  Show them the Big Dipper using the Big Dipper presets on Starry Night Pro. Or try this, especially if there are many visitors near the sun or the visitors with whom you are speaking have already heard the words, “Big Dipper.”

1. Introduction to the Model  Tell the visitors that this is a model of the seven main stars of the Big Dipper.  Help them to see the shape by closing one eye or by using the plexi “window” and/or the Big Dipper presets on Starry Night Pro.  Ask them where they have to be in order to see those seven stars line up as the familiar shape of the Big Dipper (you are trying to get them to say “Earth” or “Sun”.  Show them the “Sun” and explain that, on this scale, the entire solar system would fit inside the bulb. 2. Exploring the Model  Ask the visitors if they think these stars would appear in that familiar pattern if seen from somewhere else in the universe.  Encourage them to go and find out by walking around the model.

Try this with younger visitors, who often have trouble conceptualizing a star pattern without seeing one first.

1. Introduction to Star Patterns  Ask the visitors what a constellation or star pattern is.  Show them the Big Dipper using the Big Dipper presets on Starry Night Pro.  Show them the Big Dipper outline on the plexi “window.” 2. Seeing the Big Dipper  Bring the visitors over to the Sun and tell them that the stars on the model represent the seven stars of the Big Dipper, just like they saw on the computer.  Explain that in reality, the stars are not painted on a flat space, but are really in different places, just like they can see in the model.  Use the plexi “window” to help them see the outline of the Big Dipper. 3. Exploring the Model  Take them to a few different locations (bring the plexi “window”) and show them that the stars do not make the Big Dipper shape anywhere else in the universe except from Earth/our solar system/Sun.

Operating Tips

 The lights should all be of roughly equal brightness.  Tell a member of staff or Guide Captain if one or all of the lights have gone dim, or if a string breaks.  Be sure to wind up all of the strings before putting them away. Jumbo Big Dipper - 4 of 7 Questions and Answers

You keep calling the Big Dipper a star pattern – why not call it a constellation? The 88 constellations of the Greeks and Romans are the ones that astronomers use today to help map out the sky. According to this system, the Big Dipper is technically an ASTERISM, which is a brighter pattern of stars within a constellation, or combining several constellations. In this case, the Big Dipper is an asterism in the constellation Ursa Major, the Big Bear. However, constellations are simply patterns or images that we imagine by mentally drawing lines in the sky to connect certain stars. Since almost all cultures have star patterns/constellations that they use to illustrate or explain history or phenomena that are important to them, it is only arbitrary to call one a constellation and another an asterism. Demo: Bring up Starry Night Pro. Show the visitors some different asterisms, such as Big Dipper, Little Dipper, Summer Triangle, Winter Hexagon, Keystone, Sickle, Orion’s Belt. Give an example of how a group of stars are a constellation in one culture, but an asterism in the Greek and Roman culture. Examples: Orion’s Belt vs. Pot Rest Stars, Big Dipper vs. Drinking Gourd.

Does the Big Dipper look different when seen from different planets in our solar system? No, not noticeably. The stars are a long way away compared to the distance between planets. Demo: Show them that, on the scale of this model, the entire solar system would fit within the bulb of the light.

Will the Big Dipper stay that shape forever? The Big Dipper will not change shape noticeably in our lifetimes. However, the stars are moving away from us and away from each other – this is called PROPER MOTION because it refers to the actual motion of the stars, rather than the perceived motion because of our movement. Over thousands of years, the shape of the Big Dipper will appear to change until it is eventually unrecognizable. Demo: Open the “Big Dipper Over Centuries” file in Starry Night Pro and turn on time.

Big Dipper 2003 CE* Big Dipper 50,000 CE Big Dipper 100,000 CE

How far away are the stars? Are the stars in a single constellation all together in space? The closest star to the Earth is the Sun. It is eight LIGHT-MINUTES away, which means that light, which travels at a velocity of 186,000 miles per second, takes eight minutes to reach us. The next closest star is four LIGHT-YEARS away. The farthest objects we know of are 12 billion light years away. The stars in the Big Dipper are between 76 and 124 light-years away. Demo: Show visitors where Earth would be in the model. Then show them the signs on the floor that mark the names and distances of the different stars. Some star patterns are

* BCE (Before the Common Era) and CE (Common Era) are secular forms of BC and AD. Jumbo Big Dipper - 5 of 7 made up of stars that really are all together, such as the Pleiades, while others are a combination, such as the “V” in Taurus. Demo: Open Starry Night Pro and locate Taurus and the Pleiades. Double-click in turn on the Pleiades, the Hyades, and Aldebaron.

Aldebaron, a binary star 65 light-years away The Pleiades, a cluster of stars 400 light-years away The Hyades, a cluster of stars 150 light-years away

Why can I always see the Big Dipper in the Night Sky? From the Northern Hemisphere, the Big Dipper is a CIRCUMPOLAR star pattern. This means that it never sets below the horizon, but rather appears to move along a never-ending circle around the North CELESTIAL POLE. The celestial pole is the imaginary extension of the Earth’s axis out into space. Polaris, the North Star, is situated at the North Celestial Pole, which is why it appears to stand still while all of the others go around it. Demo: Open the “Big Dipper Through Day” file in Starry Night Pro and turn on time.

Are there really only seven stars? If you look closely at Mizar, the middle star of the Big Dipper’s handle, you will see that in fact there are two stars. Mizar is one, and the other is Alcor. These two may be just an OPTICAL DOUBLE, (two stars that are not physically associated, only along the same LINE OF SIGHT) though there is strong evidence that they are at least gravitationally bound if not actually orbiting one another. However, Mizar itself is known to be an actual BINARY star. The two components are called Mizar A and Mizar B, and these orbit one another every 5000 years. In turn, both Mizar A and Mizar B are binary stars, though these two pairs can only be resolved using SPECTROSCOPY (see Spectroscopy demo sheet).

Other Cool Stuff to Try

 Take a digital picture of the Big Dipper stars from different locations. If you could name this constellation, what would you call it?  Look at the Big Dipper from the Sun’s location. Now step back slowly. Which stars appear to move “out of place” the fastest – the close ones or the ones that are far away?

Fast Facts

 The seven stars of the Big Dipper are part of the 17 stars that make up Ursa Major, the Big Bear.  The cup of the Big Dipper pours water into the cup of the Little Dipper that is always located on the opposite side of the North Star from the Big Dipper.  We call this activity “Jumbo Big Dipper.” Actually a better name would be “Miniscule Big Dipper” because the REAL Big Dipper is some 2 x 10 17 times as big as this model – that’s a 2 with 17 zeros after it! Jumbo Big Dipper - 6 of 7

Potential Problems

 Visitors often have difficulty seeing the shape of the Big Dipper. If you encounter this, here are some things you can try: 1. Ask them to close one eye. 2. Use the plexi “window.” 3. Take a digital picture of what the visitor is seeing to reduce it to two dimensions.

 Lay stanchions out first to avoid the possibility of visitors inadvertently walking into the Sun pole. This will also help to define the space and increase visitor curiosity.

Background materials (websites, videos, articles, digital collections links) http://www.fourmilab.ch/yoursky/help/proper.html - Proper Motion of Big Dipper stars http://earthsky.org/brightest-stars/mizar-and-alcor-the-horse-and-rider -- Mizar and Alcor http://www.rssd.esa.int/SA-general/Projects/Hipparcos/hyades.html – the Hyades in 3D

Self assessment suggestions

After doing the Jumbo Big Dipper demo several times, complete the checklist and rubric below by highlighting the box that best describes your performance. Have your team leader observe your demo then complete an identical rubric. Discuss your presentation technique with your team leader along the lines of the rubric.

Assessment Tools for Jumbo Big Dipper DATE______PRESENTER______

A. Checklist of pre-requisite skills 1. Can set up stanchions, signs, the 7 lights that represent the 7 stars in the Big Dipper, and the light on a pole that represents the Sun 2. Can use the laptop and other props 3. Can cover the basic concepts covered in the teaching points

B. Rubric for Jumbo Big Dipper Demo QUALITY LEVELS OK EXCELLENT  TRAITS  Encourages discovery Ask visitors to move around Ask visitors to move around and and look for a familiar look for a familiar constellation. constellation, but tells them the Gets a sense of the visitors’ level answers at first sign of visitor of interest in discovering the frustration or disinterest, rather answers themselves. Works with than posing more questions to visitors to arrive at answers. Jumbo Big Dipper - 7 of 7 arrive at answers together. Poses additional questions to encourage discovery. Fluency at using the Can incorporate the laptop and Has a purposeful way of using laptop, Plexiglas all props in facilitating the laptop and props & brings “window” & physical them as a response to visitor positioning of visitor questions. Customizes experience Gives roughly the same Considers the age and interest to visitor introduction to each group of level of individuals in each group. visitors. Works at the level of Introduces entire group to demo, the youngest visitor in the but then later works with each group. individual at his or her own level. Content Knows a few basic facts about Is familiar with additional size comparison, etc.. information such as distance comparisons, proper motion, double stars in the Big Dipper, etc..