Remotely Interesting Mystery Cache
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Difficulty:
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Terrain:
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Size: 
(regular)
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This cache is in response to all of the satellite imagery that is currently available on the web and is for anyone who wants to learn more about satellite image interpretation and processing. You will need to travel cross-town to solve the puzzle; however there are only two stops and the second one is within walking distance of the cache.
It is easy to access satellite imagery on the web. This access provides great benefits to geocaching, and the public at large. The discipline that is dedicated to the processing of satellite images is known as Remote Sensing. The cache is not at the listed coordinates, they are for the Remote Sensing laboratory at the Royal Military College of Canada.
The images that you can download from the Internet are usually in a “true colour” format. This means that the image has been modified to emulate a colour photograph. The general public is used to viewing a true colour image, thus it is an ideal product for web dissemination. However, a true colour image holds little benefit for a professional analyst. Earth observation satellites are capable of scanning outside of the EM spectrum, beyond visible range; the portion of the spectrum that yields the most information for a Remote Sensor.
To find the cache you will have to do some remote sensing research on the Internet, some analysis of typical RS images, and some legwork.
Image 1-Thermal
This is a thermal image of Kingston. In this image; bright areas indicate ground that is relatively warmer then other areas in the image. You must figure out what is happening at the bright white line indicated by the cross-hair and circle. The answer is one word. Spell out the word and then convert it to numbers using the phone pad. The number that you get is ‘A’.
Image 2 a and b-Unsupervised Classification
These images of Kingston are a standard product of remote sensing. They are a pseudo-colour image produced by statistically grouping similar spectral signatures. Each colour represents a distinctive landcover. Travel to the location indicated by the cross-hair and circle, in the middle of the red box. The red pixels indicate that this object is spectrally different than its surroundings. Also, the object is not square, the pixels are arranged in a grid and the red ones are the ones that cover the object. Read the large 3 digit number on one side of the object. This number is data ‘B’.
Internet
Canada is a leader in one type of satellite remote sensing. The second model of this satellite type was launched successfully into space aboard a Soyuz rocket on December 14, 2007. Find out the generic acronym for the sensor used on this satellite. Convert to numbers, again using the phone pad, to get ‘C’.
Images 3a and b NDVI
Image 3 is a Normalized Difference Vegetation Index (NDVI) image of a section of Kingston, Ontario. The NDVI is produced by ratioing together the Red and Near Infrared portions of the spectrum. The benefit of a NDVI is that it shows vegetation stress; brighter areas indicate healthy vegetation, darker areas indicate stressed or non-vegetated areas. The image was scanned in the early spring before the trees had their leaves, but the grass was healthy. Using this knowledge and orienting yourself from landmarks in the image, seek out the source of the dark spot marked by the cross-hair and circle. Here you will find an object with a yellow letter on it. Use the phone pad to convert this letter to a number. Then multiply the number by 100. The result is ‘D’. Visit this location last, as the cache is located in the same area.
Location
Disregard the decimal and:
3684695+A+B=North coordinate
7635492+C+D=West coordinate
Check the final coordinates here:
(visit link)
Additional Hints
(Decrypt)
uggc://jjj.ppef.aepna.tp.pn/ Haqre n fyno bs ebpx znexrq ba gbc ol gjb ebpxf sbezvat n gevnatyr. Ybbx sbe gur vagrefrpgvba bs gjb snyyra gerrf, nebhaq gur ebpxl onfr bs bar.