A Field Trip Package for the LIGO Hanford Observatory

Some notes for the teacher
Relationships between Teachers Corner Packages and LIGO Explorer activities
A student field trip handout - the LIGO Explorer (Web copy)
A downloadable MS Word version of the LIGO Explorer
The LIGO Explorer Teachers Guide (Web copy)
A visit evaluation for teachers

We appreciate your efforts to plan a trip to the LIGO Hanford Observatory . Here is some information that may assist your preparations.

• You can find driving directions for your bus driver on our Web site at http://www.ligo-wa.caltech.edu/traveler.html
  
  
• As you turn off Highway 10 into our entrance road you will see three blue and white buildings, one after the other. The field trip activities will occur in the first building of the three. Pull into the parking lot of this building. Your LIGO host will greet you. Our field trips usually begin with a presentation in the auditorium.
  
  
• You may be aware that we have an activity packet for students that we call the LIGO Explorer. It is a four-page (double sided) handout that guides students through our exhibits. We will provide the Explorer for your students - you will not need to make copies yourself. We will also have clipboards for your students to use. (We would appreciate your help in getting the clipboards back at the end of the visit.)
  
  
• Pencils or pens are the only items that your students will need to bring. One of the exhibits requires some computation, so a few calculators may come in handy as well.
  
  
• We encourage you to bring as many chaperones as you can. Adults can help the kids have a more profitable experience and can help you have a more relaxed visit by assisting with supervision. Consider inviting your principal or other administrators as well. (We do have an ulterior motive - we think everyone should see LIGO!)
  
  
• The students can do the exhibit activities in the Explorer in any order. If you have a lot of kids it will be helpful for them to spread out amongst the various exhibits. You may wish to divide the students into groups and ask the groups to rotate amongst the exhibits. One activity occurs outside (Journey to the Stars). It would be nice to have adult supervision here to make sure that the kids don't stray from the paved walkways. A number of types of creatures (mostly small) live near the site.
  
  
• Some of the exhibits will be more challenging for the students to use than others, and the supervision needs will vary. The free-fall tube is the most complicated to use. The star walk that occurs outside requires some scaling calculations.
  
  
• The exhibits are fairly durable and we have tried to minimize the possibility of damage. The interferometer is the most delicate exhibit. Students should avoid touching the components. In general we would appreciate a minimum of fingerprints on surfaces that aren't meant to be touched - this helps us keep the building clean and attractive.
  
  
• We are more than happy to customize your visit. If you have worked on some of our Teachers Corner classroom packages and you would like to focus on the LIGO science that is related to those specific activities, we can tailor such an arrangement. Please feel free to let your host know in advance how we can structure the visit to support the work you are doing in your classroom.
  
  
• We ask that you fill out an electronic evaluation of the visit at your convenience when you are back at school. We want to provide a high quality visit experience. Your feedback will help us do so. The visit evaluation form is on our Web site along with instructions for sending it to LIGO. Thank you in advance for taking the time to send us your thoughts.
  
  
• Here is a table that shows the relationship between our Teachers Corner classroom packages and our field trip exhibits

A HANDOUT FOR STUDENTS

The LIGO Explorer

To the student: This activity sheet will take you through a number of the exhibits at the LIGO Hanford Observatory. Here's what you should do:

• Find an exhibit (you can do them in any order)
• Locate the section for the exhibit in this packet
• Read the procedure for the exhibit
• Do the procedure
• Answer the questions
• Have fun exploring the science of LIGO!

Scoping the Stars

1. What type of spectral pattern do you see when you look at white light?
   
   
2. How do the patterns from the colored lights differ from the pattern of the white light?
   
   
3. If all you could see was a spectral pattern and you couldn't see the light that produced the pattern, could you figure out the color of the light from the pattern? Explain.

A Shadow - More than Meets the Eye?

1. List all seven colors of shadows you can see at this exhibit.
   
   
2. Explain how you think a blue shadow is produced on the wall.
   
   
3. Explain how you think a magenta (purple) shadow is produced on the wall.
   
   
4. What combinations of colors produce yellow light?

An Antenna That Won't Fit on Your Car

1. What kind of experiments did Dr. Weber do with this bar? What was he trying to discover?
   
   
2. Why do you think the bar is sometimes referred to as an antenna? (You may need to ask someone how the antenna on your car works)
   
   
3. What does the bar have in common with LIGO?

A Pendulum is One Type of Falling Object

1. Everyone knows that pendulums swing. Why do we say that a pendulum also falls?
   
   
2. Is it important to keep the lid on the pendulum while it swings? Give a reason for your answer
   
   
3. Does a heavy pendulum fall at about the same rate as a light pendulum? What does this tell us about gravity?

The Little Michelson Interferometer

1. An interferometer such as this can be used as a very sensitive measuring tool. From observing the device can you see why this is true?
   
   
2. Why is an interferometer an important exhibit to have here at LIGO?

Learn More About LIGO

1. What are some ways that gravitational waves can be produced?
   
   
2. What contribution did Einstein make to our understanding of gravitational waves?

Heavy as a Rock, Light as a Feather: How Do They Fall?

Place the ball and feather on the shelf, close the tube and throw the switch. Compare the way the ball and the feather fall to the bottom of the tube. Now place the feather and ball back on the shelf and turn on the vacuum pump that is connected to the tube. The vacuum tube will remove all of the air from the tube. Set the timer for three minutes. Turn off the pump at the end of three minutes. Throw the shelf switch and again compare the way that the feather and ball fall to the bottom of the tube. Finish by venting the tube to let the air return to the inside.

1. Based on what you've seen here, why do people often think that heavier objects fall faster than light objects?
   
   
2. What is responsible for making the feather fall so slowly?
   
   
3. What does the display teach us about gravity? Does gravity cause objects to fall at the same rate or different rates?
   
   
4. Is the pull (the force) of gravity the same on light objects as on heavy objects? Explain your thinking.
   

To Our Galaxy and Beyond

1. What is a Nebula?
   
   
2. How far away is the farthest object that is mentioned in the explanations?
   
   
3. Which images do you like the best? Why?
   
   
4. What thoughts about the universe do you have from looking at the images?

Physics History

1. Scientist 1 (name, gender, country of origin, decade, contribution):
   
   
2. Scientist 2:
   
   
3. Scientist 3:
   
   
4. Scientist 4:

Journey To The Stars

1. Log onto the constellation tutorial on the computer in the common area.
   
   
2. Spend a few minutes learning to locate the star Betelgeuse in the constellation Orion.
   
   
3. Please locate and circle Betelgeuse in each of the diagrams below:
   
   

Now you will determine the distances from the Earth to 6 prominent stars in the Milky Way Galaxy. Please go to the earth's solar system indicator located outside, at the front corner of the building. We have carefully plotted points on the LIGO grounds to represent 6 stars and their relative distances from the earth. But how are you going to measure these distances?

Starting at the earth's solar system indicator, carefully count the number of steps it takes you to walk out to the star "Merak" located in the Big Dipper. (You are now using each of your step lengths as a unit of measure so make each step as identical in length as possible).

Because the distances to the stars are so huge it is very difficult to measure them using miles or kilometers. For example Merak is 475 trillion miles from the earth! It is much easier to measure these distances in light years. (A light year is the distance a beam of light will travel in one year. This is a significant distance considering light travels 186,000 miles in just one second!)

If Merak is 80 light years away, and it took _______ steps to get from the earth to Merak, then_______light years represents one of your steps.

Now determine the estimated distance to each of the 5 remaining stars by counting the number of steps it takes you to walk from the earth's solar system marker to the stars in each constellation. Complete the table on the next page with your data.

Write your Scaling Ratio here: _____ light years per step

Name of Constellation or "Group of Stars"	Name of Star	Facts about the Star	# of your steps	# of light years from earth
	Merak	Hot white star. The light you see from this star took 80 years to reach the earth.		80
	Dubhe	Is orbited by another less massive star
	Ruchbah	About four times as big as the sun
	Schedar	A very young star, about 200,000,000 years old
	Bellatrix	Will become an orange giant in a few million years. Then die quietly as a massive white dwarf.
	Betelgeuse("beetle juice")	Red super giant. If Betelgeuse replaced our sun, the surface of the star would reach out beyond the asteroid belt. Betelgeuse is 60,000 times brighter than the sun

Attraction Action

1. What will happen if you just set the ball near the rim and let it go without propelling it forward?
   
   
2. If you set the ball near the rim and propel it straight forward, what path will it follow? Why?
   
   
3. Why does the ball's orbit shrink as it continues to roll around? Does this factor affect the earth's orbit? Why not?
   
   
4. Now propel the ball towards but not straight at the center hole. Describe the path of the ball.
   
   
5. The poster on the wall behind this exhibit describes some very smart and famous people. What are the possible reasons why these people presented different facts about the nature of gravity?
   
   1. Famous, smart people tell a lot of lies
   2. Famous, smart people always find stuff to argue over
   3. The way gravity behaves has been changing over the course of history
   4. The facts we think we know change over time as people learn new things or find better ways to explain the way things behave.
      

When You Are Finished