"Mediterranean Sea Illuminated by Glowing Clouds"
An astronaut aboard the International Space Station captured a stunning image of polar mesospheric clouds, also known as noctilucent or night-shining clouds, over the Mediterranean Sea. These wispy structures form at altitudes of just over 80 kilometers and are the highest-altitude clouds in Earth's atmosphere. While historically seen only in higher latitudes during summer months, polar mesospheric clouds have become brighter and more visible in mid-latitudes. Scientists are investigating potential causes, including increased humidity in the mesosphere and the impact of exhaust plumes from space vehicle launches.