Sun outage occurs whenever the earth station, the satellite and the sun are in a direct, or near direct line with each other. Satellites are essentially electromagnetic energy sources that radiate their energy within a narrow spectrum of frequencies in specific direction (towards earth in most cases). The energy radiated by the satellite as a signal weakens as it travels through the atmosphere and needs something to increase the signal strength when it reaches the ground. Satellite dishes are dish shaped because the dish focuses the electromagnetic signal of the satellite on the receiver. The sun is a HUGE electromagnetic energy source, however and by far exceeds the output power of a satellite When the dish is pointed at the sun (because the satellite is directly between the sun and the dish), the dish is flooded with the entire electromagnetic spectrum, including on the frequencies the satellite uses to communicate with the ground station.
Essentially, the sun's radiation drowns out the satellite Fortunately, this only occurs for a few hours each day for just a few weeks out of the year, and those dates vary based on your location on the earth's surface and your angle (azimuth and elevation) to the satellite. If you know your longitude and latitude, the azimuth and elevation setting for your satellite, then calculating when the sun will be directly behind the satellite is largely a matter of a mathematical calculation.
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