This Introduction closes by citing sources of data, information, and image hard copy such as continues to be supplied by the Eros Data Center (EDC) and other distributors of products from Earth-monitoring satellites; reference is made to the Idrisi image processing program.
A principal source for Landsat imagery and much of the astronaut space photography is the EROS Data Center (EDC) in Sioux Falls, S.D., operated by the U.S. Geological Survey (USGS). EDC has assembled an Internet on-line collection of satellite images (mainly Landsat) designed to introduce the general viewer to scenes worldwide that focus on several environmental themes (e.g., cities, deserts, forests). We have linked their three-page Index for this Earthshot collection, which you can access at the Earthshots page.. To further stimulate interest in the practicality of this imagery, in addition to its beauty, we suggest taking time to sample scenes of interest and read the accompanying descriptions. We also recommend returning to this collection for repeat looks or to examine new examples. A recent Web site dedicated to showing a wide variety of Earth Science-related images from various satellites is at NASA's View Earth.
Based on sales by U.S. distribution centers, such as EROS and SpaceImaging, indicate that remote sensing is now truly a worldwide activity. The big trend in the 1990's and into the next century is the commercialization of space. Remote sensing is becoming a multi-billion dollar industry and new national organizations and private companies emerge each year to take advantage of its income-producing aspects, because they identify many applications (some covered in this tutorial) of great practical value. There is even a monthly magazine, EOM, dedicated to these increasing uses. We shall more fully touch upon trends and issues in commercialization of remote sensing as we review the outlook for the future of remote sensing in Section 21.
With this Introduction into basic principles and to characteristics of Landsat and other systems completed, and, hopefully, digested and understood, you should move on to Section 1, with its protracted tutorial development of the "whys" and "hows" of image processing (largely computer-driven). There you should gain real insight into and practice in the efficacies of remote sensing from satellites and other types of air and space platforms.
Primary Author: Nicholas M. Short, Sr.