Explain how satellite images can differ in terms of spacial and spectral resolution
Answers
Answer:this is u r answer
Explanation:The first images from space were taken on sub-orbital flights. The U.S-launched V-2 flight on October 24, 1946 took one image every 1.5 seconds. With an apogee of 65 miles (105 km), these photos were from five times higher than the previous record, the 13.7 miles (22 km) by the Explorer II balloon mission in 1935.[1] The first satellite (orbital) photographs of Earth were made on August 14, 1959 by the U.S. Explorer 6.[2][3] The first satellite photographs of the Moon might have been made on October 6, 1959 by the Soviet satellite Luna 3, on a mission to photograph the far side of the Moon. The Blue Marble photograph was taken from space in 1972, and has become very popular in the media and among the public. Also in 1972 the United States started the Landsat program, the largest program for acquisition of imagery of Earth from space. Landsat Data Continuity Mission, the most recent Landsat satellite, was launched on 11 February 2013. In 1977, the first real time satellite imagery was acquired by the United States's KH-11 satellite system
Answer:
The spatial resolution specifies the pixel size of a satellite image. The higher the spatial resolution, the more detail it will contain. Fine details can be seen in the very high and high resolution images, whilst a low resolution image will only show coarse features.
At Geoimage we break down the spatial resolution into 3 ranges
Very High resolution (sub metre): from 30cm – 1m
High resolution range: 1.5m – 10m
Low resolution: 15m – 30m
A sensor's spectral resolution specifies the number of spectral bands in which the sensor can collect reflected radiance. The choice or number of spectral bands required will depend upon the application of use. The spectral reflectance curves, or spectral signatures of different types of ground targets provide the knowledge base for information extraction. Reflectance measurements can help reveal the mineral content of rocks, the moisture of soil, the health of vegetation, the physical composition of buildings, and thousands of other invisible details.
Things to consider with regards to spectral resolution:
- Number or choice of spectral bands (red, green, blue, NIR, SWIR, thermal etc.)
- Width of each band
- Certain spectral bands (or combinations) are good for identifying specific ground features
At Geoimage we classify the spectral resolution into 5 ranges:
- Panchromatic – 1 wide Band (B&W imagery)
- Colour – 3 bands (Red, Green, Blue)
- Multispectral – 4-8 bands (RGBN)
- Super spectral – 16 bands or more
- Hyperspectral – hundreds of bands
Besides offering 30 cm resolution panchromatic and 1.2m eight band visible and near-infrared (VNIR) imagery, WorldView-3 is able to collect shortwave infrared (SWIR) imagery in eight bands. This allows the satellite to sense the VNIR spectrum as well as expand deeper into the infrared spectrum, than any other commercial imaging satellite, providing rich data for precisely identifying and characterising man-made and natural materials. Worldview-3’s eight SWIR bands span the spectrum’s three atmospheric transmittance imaging windows to capture unique information for agriculture, forestry, mining/geology and other applications. The SWIR bands open the door for automated information extraction to save time, money and lives.