AUSTIN (KXAN) – Flash flooding is a deadly threat in Central Texas, earning the area the nickname “flash flood alley,” but on Mars it may have influenced the development alien life, according to researchers from the University of Texas.
“When we think about what (Mars) looked like 3.5 billion years ago, we probably should be thinking about an environment that in some ways looks a lot like Earth,” University of Texas Associate Professor Tim Goudge said.
Goudge and a team of researchers — including Alexander Morgan, a research scientist at the Planetary Science Institute, postdoctoral researcher Gaia Stucky de Quay and Caleb Fassett, a planetary scientist at the NASA Marshall Space Flight Center — recently took a closer look at how flooding shaped the red planet.
Water on Mars
“(There are) two key pieces of evidence. One is these deeply incised river valleys,” Goudge said. Think the Grand Canyon on Earth, carved by the Colorado River flowing through it over thousands of years. Goudge says a lot of early life on Earth developed in these river valleys.
“The other really key piece of evidence is these crater lakes.” Goudge said the surface of Mars is covered in craters left by meteorites and asteroids. These craters used to fill up with water and formed lakes. Earth has crater lakes too, but they’re less common.
Earth’s crust is frequently rearranged because of plate tectonics, and is therefor much younger. Mars is much less active, meaning its crust doesn’t change very often and is considered much older.
Flooding on Mars
All that water means erosion, and it happened in two ways. Rain and rivers over thousands of years chipped away at the soil, creating those river valleys. The other way happened quickly and dramatically.
“(The crater) lakes fill up with water and breach and very catastrophically erode large canyons,” Goudge says. Think a massive, apocalyptic flood, like a dam bursting and water pouring out, creating a river valley in weeks or even days.
These floods happen on Earth, but rarely. Goudge and his team studied satellite imagery, locating where each river valley started. They found that a quarter of all erosion on the planet started at these crater lakes and was thus caused by this rapid erosion.
How could flooding influence alien life?
When scientists look for signs of life on Mars, they usually use Earth as a reference point. Since a lot of life on Earth formed in river valleys, Goudge says the planets likely don’t match up. Why? Life takes a while to form in river valleys, but if the river valleys on Mars formed rapidly due to catastrophic flooding from crater lake breaches, then life may have formed differently.
Goudge says instead we should look for life in the crater lakes. How long did they take to fill up? How often did they burst? Goudge says by answering these questions we might have a better understanding of life on Mars.