article_snippet.sent: How The satellite works: Radar works by sending out radio waves and timing how long The satellite takes for them to reflect back.
article_snippet.sent: This is because The satellite uses radar which works by sending out radio waves and timing how long it takes for them to reflect back.
article_snippet.sent: Radio waves travel through air virtually unimpeded, but materials like metal, rock and water act almost as mirrors which can help reveal those areas inundated by floods.
article_snippet.sent: It also makes no different to radar if the Earth is in darkness.
highlights_snippet.sent: The satellite, Sentinel-1a,  sends out radio waves and times how long it takes for them to reflect back .
  