Keywords: technology ocean noaa national ocean service nationaloceanservice caribbean u.s. virgin islands usvirginislands sonar metal tungsten ball metaltungstenball calibration split beam calibration splitbeamcalibration coral coral reef coralreef biogeography fish depth of field This is no ordinary metal ball. It's a specialized tool used to calibrate a split beam echosounder system. The ball is special because its target strength (the strength of the returning echo from the sonar) is precisely known. Scientists place the ball under the ship's sonar, taking hundreds of sample readings. They then compare those readings with the known target strength value of the ball. If there are differences, the ship's sonar can be adjusted—calibrated—accordingly. Learn more: oceanservice.noaa.gov/caribbean-mapping/ This is no ordinary metal ball. It's a specialized tool used to calibrate a split beam echosounder system. The ball is special because its target strength (the strength of the returning echo from the sonar) is precisely known. Scientists place the ball under the ship's sonar, taking hundreds of sample readings. They then compare those readings with the known target strength value of the ball. If there are differences, the ship's sonar can be adjusted—calibrated—accordingly. Learn more: oceanservice.noaa.gov/caribbean-mapping/ |