An anonymous reader writes: Today, a team of scientists has announced the first discovery of extraterrestrial tsunamis. A team of astronomers and geologists led by J. Alexis Rodriguez at the Planetary Science Institute in Tucson, Arizona has uncovered evidence of massive tsunamis on Mars billions of years ago. As Rodriguez reports, two separate megatsunamis tore across the red planet around 3.4 billion years ago, a time when Mars was a mere 1.1 billion years old and nearby Earth was just cradling its first microbial lifeforms. The two tsunamis created 150-foot-high shore-break waves on average, and some absolutely monster waves up to 400 feet tall. Rodriguez and his colleagues outline their tsunami findings today in the journal Scientific Reports.