Why do some Landsat browse images appear pixilated?

Question:

Answer:

This is an artifact of the browse generation process and is common for scenes that are located over flat, low-contrast areas, such as water, sand, and snow. The actual data will not appear this way.

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Landsat represents the world's longest continuously acquired collection of space-based moderate-resolution land remote sensing data. Four decades of imagery provides a unique resource for those who work in agriculture, geology, forestry, regional planning, education, mapping, and global change research. Landsat images are also invaluable for emergency response and disaster relief.