Planning a remote sensing mission

Overall problem: Where are the active lava flows on the Kilauea Volcano?

Relationship of problem in this lesson to overall problem: At this point, students have developed a fairly complex understanding of remote sensing elements and processes, a precise definition of remote sensing, and have gained an understanding of the EM spectrum and how remote sensing can help investigate active lava flows on Kilauea. The problem in this lesson is to construct a plan for using the AVIRIS remote sensing instrument to locate active lava flows on Kilauea. To do this, they will need to learn about a few additional key concepts related to the use of remote sensing instrumentation, e.g., temporal and spatial resolution and swath.

Estimated time required: 4 class periods

Student outcomes/objectives:

• Students will be able to describe the difference between temporal resolution and spatial resolution.
• Students will be able to make a remote sensing decision based on concepts that need to be considered when they are planning for a volcano mission.

Prerequisite skills or knowledge:

• Definitional knowledge of remote sensing including elements and process of remote sensing and the fundamentals of the EM spectrum
• Ability to work in teams
• Basic understanding of problem solving
• Basic reading skills
• Basic presentation skills

Teacher preparation:

• Print Student Journal / Activity sheets for these activities.
• Secure internet computers and projection equipment.
• Bookmark student websites on student machines (if not available, print and copy student problem scenario website).

Student reflection and assessment: Student reflection activities   |  Assessment

Education standards supported by this lesson:

National Science Education Standards | Project 2061 Benchmarks

National Standards for School Mathematics | National Technology Standards | National Geography Standards

Cross-curricular connections to support National Education Standards for this lesson:

math | technology | geography

Stimulate students' interest and get them to begin to think about considerations for planning a remote sensing mission by projecting either remote sensing image of the Big Island of Hawaii #1 or #2. 

Teacher note: You may want to either project these images to the class, bookmark them for students to look at during this brief discussion, or print color copies of the pictures. Image #1 is quite large and requires scrolling. 

Prompt students to look at the map of Hawaii and compare it with the remote sensing image just seen and ask:

• Where is Kilauea located on the Big island of Hawaii?

Sample student responses:

• It looks like a picture of an island. In #1 I can see land, areas of green, water, mountains. In #2 I can see more colors, lots of green areas, mountains, and what look like craters.
• It is an island because of its features, size, etc.  It is surrounded by water.
• We might get this picture from aircraft, kites, balloons, satellites, etc.
• Remote sensing is a process of obtaining information without coming into direct contact with the object being observed.

• Kilauea is toward the southwest side of the island.

Ask students to list what they know about remote sensing. Give them a few minutes to list their responses.

Prompt students to think about other factors they may need to consider before beginning the actual remote sensing mission.  

Prompt students to take a piece of paper, roll it into a tube and look at the black/white board in the classroom. 

Teacher note: You may want to use remote sensing image of the Big Island of Hawaii #1 or #2 for this activity. If you do not have projection capabilities you may want to sketch an object on the black/white board.

Ask students while looking through the tube, how many passes across the black/white board will they need to make to see the entire blackboard. 

Describe the concept of swath in remote sensing (See 5th paragraph on this web page). You may want to show them this diagram of swath.

Prompt students to write a definition of swath. See Activity sheet: Defining the terms (PRSM-1).

Ask students why the swath is important in remote sensing.

Prompt students to look at the What are we looking for site that shows different levels of spatial resolution. 

• Reveal one picture at a time and have students compare and contrast the pictures that were taken of the same objects but at different spatial resolutions.

Ask the students:

• What are the similarities?
• What are the differences?
• What would you be able to describe using image #1 that you couldn't describe using image #4?
• What could you describe using image #4 that you couldn't describe using image #1?

Teacher note: You may want to have the students view the images in reverse order to the way they are presented at the site. In this way their interest may be piqued as they try to identify the object that is revealed in the image with the highest resolution.

Introduce the relationship between resolution and pixel (picture element) by participating in the activity: How well can a Satellite see?   

Ask students how remote sensing images will be seen differently based on spatial resolution based on what they learned by doing the "How Well Can A Satellite See?" activity.

Prompt students to write a definition of spatial resolution. See Activity sheet: Defining the terms (PRSM-1).

Debrief the students by asking them to identify advantages and disadvantages to low and high spatial resolution. This discussion might be enhanced by asking them for examples of situations when one might be preferable.

Optional activity: An interesting and fun exercise might be to have the students see if they can locate Kilauea on Remote Sensing Image of the Big Island of Hawaii #1 with the aid of the map of Hawaii. The concept of resolution may be reinforced as they are likely to have difficulty scrolling on image #1 without being sure of exactly what they are viewing.

Teacher note:

• Before teaching this activity, teachers should bookmark each of the image websites in advance.

• It is recommended that teachers print images from the websites in advance if computers and/or a projector is not available in the classroom.

Teacher resources:

• Spatial resolution

• Spatial resolution, pixel size, and scale

Student activity:

• Students create a list of what they know about remote sensing, which might include:
  • Remote sensing is gathering data on things without touching them.
  • Elements of remote sensing include energy sources, transmission of data, remote sensing instrument, data processing.
  • Energy is given off from a source which is gathered and interpreted by a remote sensing instrument and turned in to an image that scientists can interpret.
  • Remote sensing data can be collected by aircraft, satellites, balloons, etc.
  • Remote sensing instruments can detect both visible and infrared EM radiation from which images can be produced.
  • Remote sensing instruments can collect data that is from heat sources, gases, etc.
  • Remote sensing instruments gather data throughout the EM spectrum.
    
    

Sample student responses:

• For example, the size of the area being sensed, the location of the area being sensed.
  

Student activity:

• Students participate in swath activity demonstration and record their definition of swath on Activity sheet: Defining the terms (PRSM-1).

Sample student responses:

• Swath is what the RS instrument "sees."  
• Understanding the swath of the instrument helps to plan flight path needed to gather the appropriate data for the mission.

Student activity:

• Students participate in short discussion on spatial resolution.
• Review the four pictures of the train set taken from different heights.
• Compare and contrast the pictures.

Sample student responses:

• The images are all of the same thing.
• You can see much more detail in picture #1 but a bigger area in picture #4.
• In image #1 I could describe the train, its color and features. I can't see those features in image #4.
• In image #4 I can see the whole landscape and see how the area is laid out. I can't see much except the train in image #1.

Student activity:

• Students participate in the activity: How well can a Satellite see?

Sample student response:

• The picture I had drawn did not look as clear when I did it using the graph paper with the larger squares on it. I had to pick one color from a few blocks and so I lost some of the detail in the picture.

Student activity:

• Students record their definition of spatial resolution on the Activity sheet: Defining the terms (PRSM-1).

Sample student responses to debrief: 

• In low spatial resolution, we can see large (gross characteristics) features in a larger ground area, but we can't see the fine details of these features.
• In high spatial resolution, we can see smaller details of the features. However, the higher the resolution, the less total ground area can be seen.

EXPLORE temporal resolution and participate in a temporal resolution activity.

Ask students how remote sensing could be used to recognize changes on the earth.

Prompt students to participate in the activity: The only thing constant is change. During this activity students will have the opportunity to "sense" changes over time. Activity 1 and activity 3  are highly recommended for helping students understand temporal resolution. 

Optional Activity: Have students sense the changes in their school's neighborhood by taking pictures from the same spot at different times, either during a single day or over a series of days. Compare the different sets of photos and have students talk about how their neighborhood has changed over time. For detailed information see the 2nd activity of Sensing change in your neighborhood. 

Teacher Note: Teachers who use the optional activity should be prepared to view this activity as long-term. It may take time to take and develop photos. Thus, it is recommended that students begin to take photos a week or so before this lesson. Then, they can analyze the pictures and develop a concept of temporal resolution during this lesson.    

Sample student responses:

• Remote sensing images can be gathered over time to monitor the Earth and show how features change. 
• Remote sensing enables scientists to monitor changes on Earth at regular time intervals. 

Student activity:

• Students participate in the activity: The only thing constant is change.

Student activity:

• Students record their definition of temporal resolution on the Activity sheet: Defining the terms (PRSM-1).

Sample student responses to debrief:

• One time, since they are not looking for changes.
• Students may indicate multiple times if they apply swath and resolution concepts, e.g., multiple passes is seeking high resolution images of a large area.

Break students into several groups and direct each group to look at the various images of Kilauea volcano.  

Teacher note:

• These images are not current images of Kilauea. We will investigate the active lava flows in the "Analyzing data" lesson by using more current (April, 2000) images.
• For the location of Kilauea on the Big Island of Hawaii refer once again to the map of Hawaii.
• For images of the lava flows in Kilauea, see the 10th, 11th, and 12th image among whole images.   

Ask students:

• How would you classify these images in terms of spatial and temporal resolution?

Prompt each group develop a plan for their remote sensing missions using the Activity sheets: Planning a mission (PRSM-2, 2A, 2B).

Prompt groups to present their plans to the class.

• Classmates assess and provide feedback to each group's plan.

Remind students to complete the Activity sheet: Reflection page (PRSM-3) in their student journal.

Summarize the lesson and introduce the next lessons, "Collecting and Analyzing data."

Student activity:

• View the various images of Kilauea volcano.

Sample student responses:

• The spatial resolution is different in each image.
• The images are of different areas and therefore may not show change over time since we aren't looking at the same place each time.

Student activities:

• Students make decisions for a remote sensing mission on the Activity sheets: Planning a mission (PRSM-2, 2A, 2B).
• Students share their remote sensing plans.

• Students complete the Activity sheet: Reflection page (PRSM-3) in their student journal.

• Prompt students to record what types of resolution problems they would need to consider, if they were planning a remote sensing mission.
  • Spatial resolution: high resolution and low resolution.
  • Temporal resolution: how many times will you fly
• Prompt students to make their own decisions for remote sensing mission. 

Assessment:

• Students define and develop an understanding of: swath, spatial resolution, and temporal resolution.
• Students differentiate between temporal resolution and spatial resolution.
• Students differentiate between high spatial resolution and low spatial resolution.

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Ideas for math lesson connections:

• The students determine a sensor's maximum spatial resolution in terms of the size of the area viewed by multiplying the instantaneous field of view (IFOV) by the distance from the ground to the sensor. (See diagram and explanation, 2.3 Spatial Resolution, Pixel Size, and Scale, in the CCRS on-line remote sensing tutorial.)

• Students practice skills using ratios and scale related to resolution and using digital images, photographs, and maps.

Related National Education Math Standards:

• Number and operations

• Geometry

• Measurement 

• Representation 

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Ideas for geography lesson connections:

• Students investigate the Hawaiian Islands. For example, the students might create a report describing the location, climate, history, culture, and geography of the island.

• Students learn how remote sensing images are produced by engaging in the "How does the spacecraft send us data?" activity. 

Related National Education Geography Standards:

• Places and Regions (#4)

• The World in Spatial Terms (#1)

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Ideas for technology lesson connections:

• Students discuss the tradeoffs associated with high and low spatial resolution.

• Students consider ethical issues associated with satellites and other remote sensing platforms being used for nonscientific purposes.

Related National Education Science Technology Standards:

• Nature of Technology (#3) ? Relationships among technologies and the connections between technology and other fields.
• Technology and Society (#4) ? The cultural, social, economic, and political effects of technology 

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Activity sheet: Defining the terms (PRSM-1) answer key

1. swath - the sensor "sees" a certain portion of the Earth's surface. The area imaged on the surface, is referred to as   the swath.

2. spatial resolution - describes how much detail in an image is visible to the human eye.

• In low spatial resolution, we can see large (gross characteristics) features in a larger ground area, but we can't see the fine details of these features.
• In high spatial resolution,  we can see smaller details of the features. However, the higher the resolution, the less total ground area can be seen.

3. temporal resolution - The frequency (number of repeat observations in a given length of time) of observations of      the same area of the Earth's surface during a given period of time.

Activity sheet: Planning a remote sensing mission (PRSM-2, 2A, 2B) answer key

 Mission statement

You are a member of an airborne mission scientist team. Your team's role is to identify where there are active lava flows on the Kilauea volcano in Hawaii. Your team has access to AVIRIS as your remote sensing instrument and NASA aircraft at Dryden Flight Research Center in California. Before starting your mission, you need to present your remote sensing plan to other scientists at NASA. So, what do you need to consider in your remote sensing mission plan? Use what you know about remote sensing and the questions below to create a mission plan.

1.      The process of remote sensing data collection:

What steps will you take to collect data for the remote sensing mission?

Step 1: Confirm the use of AVIRIS as the remote sensing instrument (example)

Step 2: Choose the appropriate NASA aircraft for housing the AVIRIS

Step 3: Create a flight plan that provides the data required to determine where the active lava flow are on Kilauea including, altitude, flight path, time of flight, etc.

Step 4: Prepare aircraft, instruments, and crew, Take off from NASA Dryden center

Step 5: Fly over Kilauea in Hawaii

Step 6: Collect the remote sensing images and return to Dryden, make interim landings as required

2.      The types of data (remote sensing image):

What kinds of remote sensing images will you collect and why will you collect those images?

• Visible images:  To see the features of the volcano and surrounding area
• Mid Infrared images: To sense steam, heat, old and new lava fields, etc.

3.      The method of data collection:

Spatial resolution: What spatial resolution are you looking for in your images (high or low) and why?

High resolution:  ( Yes    No )  circle one

Why?:

• I will collect high-resolution images since I need detailed images of active lava flows. The high- resolution images provide detailed information about specific location of the active lava flows given the land features of the volcano.

Low resolution:  (Yes  No)  circle one

Why?:

• I will collect low-resolution images since I need an entire view of Kilauea and the area surrounding it. The low-resolution images provide the information on the location of active lava flows on Kilauea and surrounding areas they may affect.

Temporal resolution and the swath: Are you looking at changes in lava flow over time?

Changes over time: (Yes  No)  circle one

Why?:

• The request for this mission was to look at the current locations of active lava flows.

Why might you fly over Kilauea more than once for this mission?

• Because the swath of the instrument may not cover the entire area of Kilauea.
• If it is determined that the question of what is happening to the lava flows over time is asked.

Use your responses to the questions on this worksheet to create a plan for conducting a remote sensing mission over the Kilauea volcano. Be sure to state the mission objective and a list the criteria for the mission including types of images you will collect and the spatial and temporal resolution requirements. You should be prepared to describe why each of the mission requirements is necessary for addressing the mission objective.

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rev. 26 MAR 01