You may or may not be familiar with the term
remote sensor. What does the term remote mean to you? What is your idea of a sensor?
If your teacher or someone else read the previous three sentences aloud to you, then you were “remote sensing.” If you are reading this page to yourself, you are remotely sensing the words on this page.
Let’s begin our study of remote sensors by exploring how you are remotely sensing the material on this page.
CHECK FOR UNDERSTANDING
1.
Discuss with a partner and then compose a definition for remote sensor.
2.
Share you and your partner’s definition for remote sensor with the class.
3.
Make a list of remote sensors that you use daily.
4.
Does your list include any of your five senses? Does your list include anything you would consider to be technology?
INVESTIGATION
1.
What remote sensor were you using if someone read this page to you aloud?
2.
If you were reading this page to yourself, what remote sensor were you using?
3.
Complete the Investigation: Which Way is
Up? on page 11.
How have others defined remote sensing? Dr.
Nick Clinton, a scientist with NASA AMES, defines it as follows:
Remote sensing is the process of obtaining information about an object without being in direct physical contact with the object.
Dr. Nick Clinton, NASA AMES
Let’s see how Dr. Nicholas Short, a NASA scientist describes remote sensing :
If you have heard the term "remote sensing" before you may have asked, "what does it mean?" It's a rather simple, familiar activity that we all do as a matter of daily life, but that gets complicated when we increase the scale at which we observe.
As you view the screen of your computer monitor, you are actively engaged in remote sensing.
A physical quantity (light) emanates from that screen, whose imaging electronics provides a source of radiation. The radiated light passes over a distance, and thus is "remote" to some extent, until it encounters and is captured by a sensor
(your eyes). Each eye sends a signal to a processor (your brain) which records the data and interprets this into information.
Several of the human senses gather information almost entirely by perceiving a variety of signals, either emitted or reflected, actively or passively, from objects that transmit in waves or pulses.
Thus, the ear records disturbances in the atmosphere as sound waves, and the eye records visible light as light waves. Heat.
FIND OUT MORE
1.
Learn more about remote sensing through
Dr. Nicholas Short’s Remote Sensing Tutorial sponsored by NASA http://rst.gsfc.nasa.gov/
2.
Learn about the history of remote sensing reviewing History of Remote Sensing: From
Pigeons to Satellites (See Additional
Resources).
Airborne Research and Remote Sensing, © AREE 2009 1

All sensations that are not received through direct contact(such as touch) are remotely sensed.
What Color is Sugar?
When asked, “What color is sugar?” most people will respond “white.” Well, you might be surprised to learn that this isn’t an easy answer.
How we perceive color is related to the way our remote sensors work as well as with how light travels through different materials.
INVESTIGATION
4.
What color is sugar? Complete the
Investigation: What Color is Sugar? On page 12.
Light travels in a straight line while moving through a uniform medium. The bending of light, or refraction, occurs when light passes from one medium to a different medium. Individual sugar crystals are transparent and have edges that are not uniform. When a large number of sugar crystals are placed together, light cannot pass completely through and is scattered, or refracted.
Investigations of various size crystals and other substances have shown that the deflected color depends on the size of the particles. For example, the scattering of very small particles such as those that make up our atmosphere explains why the sky is blue. Larger particles can scatter all colors equally and are perceived as white.
You can observe the refraction of light by placing a pencil in a glass of water and observing that the pencil appears to be bent.
Light is a Wave
Heat and light travels 93 million miles from the sun to the Earth. Heat and light do not travel as atoms but as invisible waves.
Both waves of heat and light travel at the speed of light, 300,000 km/sec
(186,000 mi/sec).
White Light and Sunlight
Think back on the decomposition of sugar activity. If sugar crystals are clear, then why can
it be perceived as white by the human eye?
Light from the sun is considered white light.
When white light is passed through a prism it is broken up (refracted) into individual bands of red, orange, yellow, green, blue, indigo and violet (ROY G BIV). The combined colors of ROY
G BIV are perceived as white.
Another way the human eye perceives light is through absorption and reflection. Look at the yellow rectangle to the left. All the colors of visible light are being absorbed except the yellow that is being reflected back to your eye.
Airborne Research and Remote Sensing, © AREE 2009 2

The Electromagnetic Spectrum
Energy in many different forms travels as waves including: radio, micro, infrared, visible light, ultraviolet, x-rays and gamma. These forms of energy can be collectively referred to as the
Electromagnetic Spectrum.
What characteristic separates all the different parts of the electromagnetic spectrum? All are traveling at the speed of light but each is differentiated from the other by its wavelength.
CHECK FOR UNDERSTANDING
5.
Which types of waves are the longest?
How long are they (in meters)? What can this size be compared to?
6.
Which types of waves are the shortest?
How long are they (in meters)? What can this size be compared to?
7.
Where is the crest of a wave found?
8.
Where is the trough of a wave found?
9.
Which color of visible light has the longest wavelength?
10.
Which color of visible light has the shortest wavelength?
Wavelength is measured from crest to crest.
The range of length of wavelengths is from the size of a football field to that of a nucleus of an atom.
Even more interesting is that different animals can see different wavelengths. We call the visible light the wavelengths seen by the human eye. For example we can see from the diagram for visible light that red has the longest wavelength and violet has the shortest wavelength. However, we can use special instruments to extend our vision.
Airborne Research and Remote Sensing, © AREE 2009
FIND OUT MORE
3.
Some animals can see wavelengths beyond the visible light spectrum. Honey bees, for example, can see light between wavelengths
300 - 650 nanometers. Click on the link below for information on amazing remote sensors of animals: Amazing Animal Senses http://faculty.washington.edu/chudler/amaz e.html
.
3

Seeing Through the Smoke
The image below is a digital image of a fire in
Yellowstone National Park. view the fire wavelengths other than visible light (ROY G BIV) what part of the electromagnetic spectrum might reveal the most information about the fire?
The image below is using wavelengths other than the visible part of the spectrum to gain information about the fire. The brightest spots are where the fire is still burning. The red and orange are places that fire has already burned.
What do you see in this picture? How do you think this picture was taken?
The picture is a digital image showing natural colors. Natural colors are those wavelengths of the visible spectrum. The main feature of the image in natural color is the smoke from the fire.
The image was taken from an airplane then a computer was used to produce the image to be viewed and shared. This is similar to the way we perceive images with light entering the eye, exciting photo receptors of the retina, whose signals are passed along the optic nerve to be interpreted by the brain.
What if you could see through smoke what might the fire look like? If you were looking at the fire from above you would see something similar to the picture of the smoke. If you could
Airborne Research and Remote Sensing, © AREE 2009
This image was produced using wavelengths from the infrared part of the electromagnetic spectrum. Using a computer these infrared wavelengths are assigned a color that can be perceived by the human eye. This type of image in known as a false-color image and we will learn more about how these and other images are produced.
FIND OUT MORE
4. Click on the link to view a movie presented by NASA scientist Dr. Michelle Thaller on infrared light and the electromagnetic spectrum. Click on the link: Infrared- More
than Your Eyes Can See http://coolcosmos.ipac.caltech.edu/videos/ more_than_your/index.html
4

Views from the Air and the Ground
Examine the two images of a prominent feature of Moro Bay California. One was taken from the ground and the other from a plane at an altitude of 37,000ft. Which is the ground view and which is the plane view? What are the clues from each picture that you used to make your decision?
Let’s apply what we have learned about light to our analysis of images. Remember Dr. Clinton’s definition: Remote sensing is the process of obtaining information about an object without
being in direct physical contact with the object.
What types of instruments do you think Dr.
Clinton’s might be referencing?
Take a look at the following four images. What do you think the objects are? What instruments do you think were used to detect photons used to produce these images? How far from the object (millimeters, centimeters, meters, kilometers) do you think the instrument was from the object? Where was you think image taken from?
CHECK FOR UNDERSTANDING
11. Describe the four images by completing the table below.
Description of Image
Instrument
Used
Distance from Object
Location
Taken From
Complete the above table before you continue reading. Once your table is complete, your teacher will provide you with a description of the images. Correct or add to information in your table based on these descriptions.
FIND OUT MORE
5. Click on the link to view an animation of TERRA’s orbit of the Earth:
TERRA’S Orbit http://terra.nasa.gov/Publications/laquila/VID/TerraOrbit.mpg
Airborne Research and Remote Sensing, © AREE 2009 5

NASA Superheroes
Review the diagram of the electromagnetic spectrum on page 3. Pretend for a moment you can be a superhero with superhero sight.
What parts of the spectrum would you choose to
augment
your sight? Would you want to see at a higher frequency of wave lengths such as ultraviolet (many insects can process portions of ultraviolet light wave lengths to produce images) or would you choose to see at lower frequency wave lengths such as infrared?
NASA has superheroes in space looking back at the Earth collecting data in wavelengths that include infrared and visible light. Can you guess what they are? You were introduced to them earlier.
Do you remember this picture? This image was taken using MODIS aboard the TERRA satellite.
Below is another interesting image. It was also taken from space via satellite. This image, however, was taken using a different superhero, ASTER--which uses different wavelengths of visible light and infrared than
MODIS.
This ASTER image is of
Mt. St. Helens in
Washington taken shortly after it erupted in 2000.
NASA has a third superhero, MASTER, which combines the vision of both MODIS and ASTER. MASTER can “see” all the wavelengths that both MODIS and ASTER can also see.
Unlike MOSID and ASTER, MASTER is placed not on a satellite but instead on an airplane, such as
NASA’s DC-8 flying laboratory. Below is a diagram of the MASTER instrument. Notice the arrows: labeled Visible, Near IR, Mid IR and
Infrared. These refer to the different wavelengths of infrared and visible light detected by MASTER.
The MASTER is used by NASA to gain information about Earth systems. The MASTER instrument can be flown aboard more than one kind of aircraft.
Why would NASA want to be able to place an instrument on more than one kind of aircraft?
Different aircraft? Planes are equipped to fly at different altitudes and speeds, and using
MASTER on different planes will allow scientists to collect information from a variety of altitudes.
FIND OUT MORE
6. Conduct a web search to compare capabilities of four planes that support the
MASTER. Start your search at http://masterweb.jpl.nasa.gov/ . Construct a table like the one below. Consider including pictures of the images in your table
Plane Speed Altitude Your Choice
Airborne Research and Remote Sensing, © AREE 2009 6

MASTER’s Superhero Sight
MASTER is an instrument for looking back at the
Earth’s surface. It is like your eye in that it detects photons. Think of photons as little packets of energy that have a specific or distinct wavelength. MASTER is a photon detector just as your eye is a photon detector. Light reaching the
Earth can be transmitted (pass through), absorbed or reflected.
CHECK FOR UNDERSTANDING
12.
What is a photon?
13.
How is MASTER like your eye?
14.
Why are green plants green? (Hint: Think back to page 2 and why the yellow rectangle is yellow.)
MASTER “sees” in 50 bands of visible light and infrared energy. Imagine the wavelengths of the electromagnetic spectrum for visible light and infrared separated into 50 distinct bands or wavelengths.
FIND OUT MORE
7. Can you divide a square into 50 rectangles?

First Try: Take a piece of paper that has been cut as a perfect square. Divide it in half to make two rectangles, and then keep dividing until you have 50 rectangles. Are all your rectangles the same size?

Second Try: Think of a way to divide the rectangle so that all rectangles are the same size.
The image below shows the rectangular areas where MASTER collects data when housed on
The image above demonstrates how MASTER functions as a photon detector. The yellow arrows represent energy from the sun. This energy includes photons of infrared, v i s i b l e light and ultraviolet wavelengths. When this energy enters the Earth’s atmosphere some of it is absorbed, some is reflected and some passes through (transmitted) to the Earth’s surface.
Of the photons that reach the Earth’s surface, some of the infrared photons are absorbed and some are then radiated from the object. The visible light photons are either absorbed or reflected. These are the photons that MASTER can detect—but only those photons that are one of 50 specific wavelengths.
Do you think that the retinas of your eyes detect more or less wavelengths than MASTER? (Hint:
Remember MASTER is a superhero.)
Our eyes detect only wavelengths of visible light, but MASTER detects both visible and infrared photons/wavelengths. Therefore the human retina detects less than 50 bands.
8 n. mi.
4 n. mi
65,000 ft
24 in.
LENS
8 n. mi.
12 in.
LENS
21.4 n. mi.
2 n. mi.
at NADIR
6.6 n. mi./min
IRIS II
Panoramic Camera
MAS, MASTER,
AOCI, MAMS
TMS
20 n. mi.
16 n. mi
6 in.
LENS
16 n. mi
Airborne Research and Remote Sensing, © AREE 2009 7

Comparing MASTER and the Human Eye
How the Eye Detects: Do you recognize the animal in the image below? The reflected photons of the visible spectrum are entering the pupil and exciting cells of your retina.
(Remember your findings in the Which Way is
Up activity.) The image of the otters is literally reversed on your retina.
Because MASTER’s “brain” is external to the instrument, it requires a computer to process the information.
The Venn diagram below demonstrates two differences between MASTER and the human eye. What other differences can you think of?
How MASTER Detects: Like your eye, MASTER is a detector of photons. MASTER has an opening for photons to enter and registers the photons as either a 1 (detected) or 0 (not detected) for photons of the 50 bands it can measure in the infrared and visible light portions of the electromagnetic spectrum.
How the Eye Processes the Image: Your eye retina sends signals via the optic nerve to your brain for processing, and the end result is that you recognize colors and shapes that make up the image.
Photo of the Human Eye
How MASTER Processes the Data: MASTER records what it “sees” as data, and this data must be processed further before it can be used.
Airborne Research and Remote Sensing, © AREE 2009
MASTER
Information processed by a computer to produce an image
An opening for photons to pass through and a photon detector
R O Y G B I V
HUMAN EYE
Information processed by brain to produce an image
Processing MASTER Data on the Computer
Understanding how images are placed on the computer monitor will help us understand how the photons/specific wavelengths that MASTER detects can be processed into an image by a computer. Imagine looking at a computer screen. Think of the back of the screen you are looking as being shot at by three guns that can make the screen light up--a red gun, a green gun and a blue gun.
When all three guns are shot at the screen at the same time, the screen will appear white. When none of the guns are shot at the screen, it appears black. All the other colors we perceive are simply different combination of energy passing through each gun to the computer screen. Remember that MASTER has 50 bands of infrared and visible light it can detect. The data that MASTER collects can be assigned as a wavelength to one or more of the three guns to produce different types of images.
FIND OUT MORE
8. View Eye Interactive, an animation of light entering eye produced by
BiologyMad.com: www.biologymad.com/resources/eye.swf
8

B
Comparing MASTER Images
Remember that MASTER collects data which is transferred to a computer, which processes the data in one or a combination of the fifty bands that MASTER can detect. Below are a series of images collected on July 22, 2009 when the
NASA DC-8 flying laboratory flew two passes over Monterey Bay, California and the MASTER instrument was programmed to collect information. Each of these images may be enlarged by clicking on the icon in the corner of the image. absorbs red wavelengths. The kelp show ups darkest in the second image because chlorophyll reflects green most strongly in that part of the visible spectrum. The first image, where band 9 is assigned as the energy wavelength for all three monitor guns, highlights all vegetation as brighter than its surroundings.
IMAGE 3: Grayscale Image Using Infrared Bands
IMAGE 1: True Color Image of Monterey Bay
IMAGE 4: Grayscale Green Image
IMAGE 2: Grayscale Image of Image 1
Image 2 uses band 9 in a grayscale image to highlight certain aspects of the scene. Grayscale images are those images where the same wavelength has been assigned to all three guns responsible for the image. Images 3 and 4 are in also grayscale images, but use green and red to highlight features.
Why is the kelp darkest in the grayscale green image? The kelp appears the least dark in the grayscale red (third) image because chlorophyll
Airborne Research and Remote Sensing, © AREE 2009
IMAGE 5: Grayscale Red Image
The grayscale infrared image above uses infrared bands of the electromagnetic spectrum
(instead of band 9) and provides a slightly different view of the same scene. Cooler areas are darker than warmer areas. The curved
9

bright white line in the upper right corner is
Highway 1.
Can MASTER see in the Dark?
At night, the Earth’s surface continues to radiate infrared wavelengths. MASTER can still collect data that can be processed into an image. If
Image 5 had been taken at night, the water would be brighter than the land, because it would have retained much of its internal heat.
The land would appear darker, because it already radiated its absorbed solar energy.
Looking for Chlorophyll boat track for the John Martin. The John Martin is one of the research vessels for the Monterey
Bay Aquarium Research Institute. The term used to describe researchers making measurements in the field is “in-situ” measurements.
IMAGE 6: False-Color Image of Boat Track
IMAGE 6: False Color Image
Image 6 is a false-color image like the ASTER image you saw of Mt St Helens. False-color images are often produced to highlight a specific feature in a scene. What features are highlighted in Image 6? Hint: the kelp in the water is red as is the square features in the top left corner and the hillsides on the right. What does kelp have in common with these land features? Answer: Chlorophyll-containing vegetation! Chlorophyll is the material in green plants, some protists and some bacteria that allow them to make their own food using carbon dioxide plus water in the presence of sunlight to produce oxygen plus sugar.
Complimenting MASTER from the Ground
One of the things that researchers want to know is if their instrument is calibrated correctly. One way to do this is to go out in the field and collect data at the same time the aircraft flies over.
Image 6 is a false-color image that includes a
Airborne Research and Remote Sensing, © AREE 2009
CHECK FOR UNDERSTANDING
15.
Image 1: Identify A, B, and C.
16.
Image 2: What do you think makes up the brightest parts of the image? What are the brightest portions near the shore
17.
Images 2, 3, 4: Examine the kelp in the ocean near the center shoreline. In which picture is the kelp the darkest? The lightest?
18.
Image 5: Which is the warmer surface – water in the bay or land?
19.
Image 5: What are the darker patches on land?
20.
Image 5: Why is Highway 1 so much lighter than its surroundings?
21.
Image 5: Why can you no longer seek the kelp in this image?
22.
Image 6: Which of the three guns (red, green or blue) would the wavelength of band 9 be assigned to get this image?
10

Investigation 1: Which Way is Up?
Question and Challenge:
How does your eye work?
Conduct the following investigation to explore how your eye sees objects and transmits data to your brain for further processing.
Materials:
Empty salt container
(or similar sized cylinder), flashlight, wax paper, rubber band that fits around cylinder.
Procedures:
1.
Remove the top of the salt container with the spout so that it is completely open at one end.
2.
Use a pen to poke a small hole in the intact side of the salt container.
3.
Cover the open side of the salt container with wax paper.
4.
Secure the wax paper with a rubber band.
5.
Have your partner position the pencil and flashlight as shown below, making sure that your pen points toward the floor. Look through the small hole and determine the direction of the shadow on the wax paper.
6.
In the circle below, draw your observation.
Be sure to observe the direction of the pen in the shadow image.
Image observed when pen points downward
.
7.
Reverse the direction of the pen to point upward. Draw your observation. What did you notice about the direction of the pen’s shadow??
Image observed when pen points upward
.
Airborne Research and Remote Sensing, © AREE 2009 11

How the Eye Sees
The salt container with the wax paper can be thought of as a model for the human eye.
CHECK FOR UNDERSTANDING
23. Reproduce the image of the eye below and label the parts of the eye that were represented with the salt container, pinhole, and wax paper. www.nei.nih.gov/health/eyediagram/images/diagram.gif
Investigation 2: What Color is Sugar?
Question and Challenge:
What color is sugar?
Conduct the following investigation to understand how the human eye detects color.
Background Information:
In this investigation, we will decompose ordinary table sugar to understand how the eye perceives color. In chemical decomposition reactions, one compound decomposes into other compounds of elements. The equation has the form:
AB  A + B where AB is the reactant and A and B are the
products. The formula for table sugar, sucrose, is C
12
H
22
O
11
. When sucrose decomposes, it breaks down into carbon and water.
C
12
H
22
O
11
.  12 C + 11 H
2
O
Airborne Research and Remote Sensing, © AREE 2009
Materials:
Goggles, aluminum foil
(shaped into a small scoop), sucrose, candle
Procedures:
1.
Place a tiny amount of sucrose on one end of an aluminum foil scoop.
2.
Wearing goggles, place the end of the scoop with the sugar1/2 cm above the tip of the flame which is the hottest part of the flame
3.
Gently heat the sugar over a burning candle. Avoid placing the scoop into the flame because that causes sooting.
4.
Record as many details as possible of what you observe happening as the sugar decomposes.
CHECK FOR UNDERSTANDING
24.
What is a decomposition reaction?
25.
What elements make up sucrose?
26.
What color is sucrose?
27.
What does sucrose decompose into when heated?
28.
Complete the following table:
Substance
Sucrose in
Formula Color solid form
Sucrose in liquid form
Carbon dioxide
Water
Carbon
29.
What have you learned about the color of sucrose?
30.
Imagine a pencil in a beaker of water.
When you view it from the side, the pencil appears to be bent or broken. What causes that distortion?
31.
How does the appearance of the pencil in the beaker of water help explain the color of sucrose?
32.
How does the appearance of the pencil in a beaker of water and the color of sucrose help explain how the human eye works?
12

Key Words
Electromagnetic spectrum, refraction, reflection, absorption, transmission, radiation,
MASTER, true-color, false-color, grayscale, band, photon, wavelength, in-situ
Curriculum-Framing Questions

Essential Question: How do we use data collected from NASA airborne missions to help us understand interactions between
Earth systems and identify solutions to environmental problems?

Unit Question: What do remote sensors contribute to Earth systems science?
Learning Objectives Students will

Explain how remote sensing works

Identify differences between how the human eye and MASTER instrument detect photons.

Identify differences in MASTER images.
National Science Standards
Assessment Activities
1.
VENN Diagram of MASTER and Human Eye
Characteristics: Have students create a
VENN diagram to comparing and contrasting MASTER with the human eye.
For full credit, the diagram should include at least three unique characteristics of
MASTER, three unique characteristics of the human eye, and three characteristics that they have in common.
Science as inquiry, Science and technology,
Science in personal and social perspectives,
History and nature of science
Resources and Activities:

Curriculum Brief: Remote Sensors: Photon
Detectives

Investigation: Which Way is Up?

Investigation: What Color Is Sugar?

Investigation: Using Google Earth



Venn Diagram Assessment Activity

Graphic Illustration Assessment Activity
2.
Using a Graphic to Convey Information
about How the Eye Receives Sight: Create a graphic illustration of how light travels from its source to the retina of your eye. Provide a diagram such as the one below. Be sure to label all important features and number the steps in the process.
Hint Light rays travels in a straight line through a medium until entering a new medium in which it can be bent
(refracted).
Note for the purposes of this drawing the retina was drawn as a straight line. In reality the retina follows the curve of the back of your eye.
Airborne Research and Remote Sensing, © AREE 2009 13

FIND OUT MORE
9. Complete the Photon Detectives Google
Earth Investigation.
26.
27.
28.
28.
30.
31.
32.
20.
21.
22.
23.
24.
25.
13.
14.
15.
16.
17.
18.
19.
5.
6.
7.
8.
9.
0.
11.
12.
Answers to Check for Understanding Questions
1.
2.
3.
4.
Related AREE Units o Introduction to Earth System Science and
Remote Sensing (Airborne Science Research
and Remote Sensing Networks) o Discovering the Living Sea from the Air ,
Mapping the Bay, and Geometry Goes
Airborne (MASTER Goes Airborne) o Remote Sensing and Agriculture, Examining
Agricultural Airborne Data with
Mathematical Problem Solving Techniques, and NASA and Farmers Partner UP
(Agriculture Goes Airborne)
Resources on Harmful Algal Blooms o Rising Tides http://phytoplankton.gsfc.nasa.gov/risingti des/
Resources on Remote Sensing o Airborne Remote Sensing Basics http://hydrolab.arsusda.gov/rsbasics/noise.
php o What is Airborne Remote Sensing? http://ide.ed.psu.edu/kaams/kaams/lesson plans/whatisARS/over.html
o Canada Centre for Remote Sensing http://www.ccrs.nrcan.gc.ca/resource/inde x_e.php#tutor
References
Burns, J.E. (1997). From the Rainbow Crow to
Polar Bears; Introducing Science Concepts through Children’s Literature. Science Scope,
October, pgs. 14-16.
Acknowledgements
This unit was developed by John Burns, AREE
Master Educator, as part of the Summer 2009
Airborne Research Experience for Educators, funded by the NASA Johnson Teaching From
Space Program.
Direct inquires to Shaun Smith, AREE Project
Director, NASA Dryden Flight Research Center, shaun.smith@nasa.gov
.
Airborne Research and Remote Sensing, © AREE 2009 14

IMAGE 1: TYPHOON MOLAVE
This image of Typhoon Molave was taken it was building from a tropical storm taken July 18, 2009. Can you see the eye of the storm?
The storm’s maximum sustained winds were 55 -60 knots (63-70 miles per hour). NASA’s Terra satellite captured this photo-like image.
MODIS (or Moderate Resolution
Imaging Spectroradiometer) is a key instrument aboard the Terra (EOS
AM) and Aqua (EOS PM) satellites.
Terra's orbit around the Earth is timed so that it passes from north to south across the equator in the morning, while Aqua passes south to north over the equator in the afternoon. Terra MODIS and Aqua
MODIS are viewing the entire Earth's surface every 1 to 2 days.
IMAGE 2: AREE MASTER TEACHERS IMAGE 3: DINOFLAGELLATE
Two Airborne Research for Educators
(AREE) participants, on board the boat the John Martin, departing Moss
Landing, Monterey Bay, California.
These two educators were joined researchers from Monterey Bay
Aquarium Research Institute (MBARI) and University of California Santa
Cruz who are investigating algal blooms that occur in the Monterey
Bay. The image was captured with a digital camera from about 2 meters from the AREE educators.
This image of dinoflagellate,
Akashiwo was taken with a microscope. Akashiwo uses its whiplike tail to move up and down the water column in the ocean. It is one of a few species that can produce toxins and contribute to a harmful algal bloom in favorable conditions.
The image was produced with the use of a microscope.
Airborne Research and Remote Sensing, © AREE 2009 15
IMAGE 4: RODEO-CHEDISKI WILDFIRE
Images of Arizona’s Rodeo-Chediski wildfire were acquired by NASA’s MODIS Airborne
Simulator from the ER-2 aircraft. The two images show the extent of the burn area
(450,000 acres) and pinpoint areas of active burning at the time of the photo. Images include both true-color images and false-color images designed to highlight the burned areas. The false-color image shows the southern portion of the fire, and reveals that not all the terrain within the fire’s perimeter burned to the same degree. Burned areas are red and remaining vegetation is green. In the center of the image, the bright orange pixels are actively burning fire, and the smoke drifting southward from the blaze appears blue. Burned area at the top of the true-color image appears charcoal, and a smoke plume drifting southwest from the center of the image reveals the location of actively burning fire.

Below are a series of collected on July 22, 2009 when the NASA DC-8 flying laboratory flew two passes over Monterey Bay, California and the MASTER instrument was programmed to collect information. Each of these images may be enlarged by clicking on the icon in the corner of the image.
IMAGE 1: True Color Image of Monterey Bay IMAGE 2: Grayscale Image of Image 1 IMAGE 3: Grayscale Image Using Infrared Bands
Image 2 uses band 9 in a grayscale image to highlight certain aspects of the scene. Grayscale images are those images where the same wavelength has been assigned to all three guns responsible for the image. Images 3 and 4 are in also grayscale images, but use green and red to highlight features.
Why is the kelp darkest in the grayscale green image? The kelp appears the least dark in the grayscale red (third) image because chlorophyll absorbs red wavelengths. The kelp show ups darkest in the second image because chlorophyll reflects green most strongly in that part of the visible spectrum. The first image, where band 9 is assigned as the energy wavelength for all three monitor guns, highlights all vegetation as brighter than its surroundings.
IMAGE 4: Grayscale Green Image IMAGE 5: Grayscale Red Image IMAGE 6: False Color Image
Image 5 is grayscale infrared image which uses infrared bands of the electromagnetic spectrum (instead of band 9) and provides a slightly different view of the same scene.
Cooler areas are darker than warmer areas. The curved bright white line in the upper right corner is Highway 1. At night, the Earth’s surface continues to radiate infrared wavelengths. MASTER can still collect data that can be processed into an image. If Image 5 had been taken at night, the water would be brighter than the land, because it would have retained much of its internal heat. The land would appear darker, because it already radiated its absorbed solar energy.
Image 6 is a false-color image like the ASTER image you saw of Mt St Helens. False-color images are often produced to highlight a specific feature in a scene. What features are highlighted in Image 6? Hint: the kelp in the water is red as is the square features in the top left corner and the hillsides on the right. What does kelp have in common with these land features? Answer: Chlorophyll-containing vegetation!
Airborne Research and Remote Sensing, © AREE 2009 16