Satellites are the key to understanding Pacific volcanoes

 A massive underwater eruption of volcanic activity occurred on the South Pacific near Tonga on Saturday the 17th of July, satellites were on hand to record what was happening.

This is due to the large and expanding number of Earth observation spacecraft flying overhead. Certain spacecraft are constantly monitoring specific regions of the Earth which means their data can be analyzed immediately and others are charged with conducting follow-up observations. All the data the satellites have gathered will help the response to emergencies, and will help scientists understand the emergency. The weather satellites There are several spacecraft that are monitoring weather patterns from 36,000 km (22,370 miles) above Earth. They survey the entire hemisphere every couple of minutes and relay pictures of the things they observe to the ground , allowing them to provide current forecasts. When an eruption occurs that releases ash, it can be difficult to determine what's happening on the ground - in the absence of radar technology that penetrates clouds and ash. The EU's Sentinel-1A flew by the volcano on Saturday night it was evident that a large portion of the edifice over the waters of the Pacific Ocean had been destroyed.