These two prominent rayed craters are located at 40 degrees N, 124 degrees W. Bright halos extend as far as 2 crater diameters beyond crater rims. Individual rays extend from halo. Bright streak extending from middle top to lower is unrelated to the two craters. Craters are 40 km in diameter. This image (FDS 275) was taken during the spacecraft's first encounter with Mercury
The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.