Chagan "Atomic Lake" in 2009 and 2010. Circular basin above the center of the image is the crater created by Soviet nuclear test in 1965; on the 2010 image it appears to be connected with a shallow reservoir on Shagan River, allowing water exchange.
USGS/NASA Landsat Program; comparison made by <a href="//commons.wikimedia.org/wiki/User:Szczureq" title="User:Szczureq">Szczureq</a>
Images from USGS: <a rel="nofollow" class="external text" href="https://landsatlook.usgs.gov/">LandsatLook Viewer</a>