This image shows the first flash of sunlight reflected off a lake on Saturn's moon Titan. The glint off a mirror-like surface is known as a specular reflection.
The first flash of sunlight confirms the presence of liquid on the part of the moon dotted with many large, lake-shaped basins. Cassini scientists had been looking for the glint, since the spacecraft began orbiting Saturn in 2004. But Titan's northern hemisphere, which has more lakes than the southern hemisphere, has been veiled in winter darkness.
The ray of light was detected by Cassini's visual and infrared mapping spectrometer (VIMS). Scientists were able to correlate the reflection to the southern shoreline of a lake called Kraken Mare. The sprawling Kraken Mare covers about 400,000 square kilometres an area larger than the Caspian Sea, the largest lake on Earth.