About Satellite Imagery

Viewing the Earth from space and accurately depicting its land and water features is made possible by satellite imagery. Satellite imagery uses digital electromagnetic technology to capture dynamic images of the Earth's features. These images can be used for a variety of purposes, and they give the viewer a deeper understanding of the area in focus.

Identification

The digital technology of satellite imagery uses several bands of the light spectrum, including visible light and infrared light, to accentuate the images captured through the images' dimensional layers. The satellite's sensors detect and process the different types of light surrounding and within the image of focus. The image is sent to computers that receive and record the image for later use. Satellite imagery covers a vast area of the Earth, unlike standard photography, which cannot capture as much information in one photograph.

History

Historically, satellites have been used for photography since 1959, when the first images of the Earth were transmitted through a weather satellite named the TIROS-1. These photographs were taken by the Explorer 6, a United States satellite, on August 14, 1959. Since then, satellites have been used to capture true-life images of the Earth in its vastness, including geographical and weather images as well as images used for identification, such as famous landmarks that are normally difficult to reach.

Function

Satellite imagery has evolved to become a reliable and functional tool in a vast array of fields, such as education, conservation, agriculture, regional planning, and geology. In geology, satellite imagery provides accuracy and detail to elevation maps, which was previously a challenging task. Satellite imagery makes it possible to view the Earth's surface features effortlessly, thereby making it easier to determine the best location for environmental endeavors. Satellites make it possible to examine the environment on a larger scale. Decisions can be made to cause minimal impact on the environment and its wildlife, when planning agricultural areas or other regional developments.

Types

There are two types of satellite imagery: Visible Satellite Imagery (VIS or VSB) and Infrared Satellite Imagery (IR). Visible satellite imagery uses solar radiation to capture images of the Earth's surface and the atmospheric elements. It can take images of snow, clouds, and many of the formations on the earth.
Infrared satellite imagery uses infrared technology to capture sensory data of the fluctuations in temperature throughout the atmosphere. Clouds of various types can be distinguished based on temperature and position, a strong indicator of weather conditions. Clouds increase in temperature degrees when they appear lower in the atmosphere. Weather can be determined by the positioning of cloud formations and storm movements, through infrared satellite imagery.

Warning

The advancements of photography through satellite imagery are not without drawbacks and concerns. Satellites are constantly orbiting the Earth and taking snapshots of its surface. This yields a tremendous amount of data, which consumes a lot of time for sorting, categorizing and usage. Satellite images are also not always clear, due to heavy clouds and weather formations. The use of satellite images is limited by a licensing procedure from commercial satellites. A license must be obtained from these companies before their images are offered for resale or other uses.
Another concern about the satellite images is the privacy issue it raises. Many people find it intrusive and would prefer to make images of their home inaccessible.

Considerations

Vivid, dimensional, accurate and vast, are words that describe the images produced by the satellites. Satellite imagery is a very dynamic field, as it captures the Earth and its atmospheric conditions in ways that are not possible to achieve in traditional aerial photography. Employing several forms of light, whose results are recorded in layers with the visible light, gives the photograph enhanced character.

Resources

• Satellite Imagery
• Terra Server Online Imagery