(Image credit: NASA)
We tend to think of Mars as dusty, dry, and barren, but vein-like rivets carved throughout the Red Planet's surface suggest the world was once flowing with water. But where exactly that possibly life-bearing liquid came from — rainclouds? underground? — has been a matter of contention among scientists.
But a new study by Kat Scanlon, a geological sciences graduate student at Brown University, takes a close look at the orographic composition of Mars' surface. (Orography is the study of how mountains form.) According to the findings, it looks like the Red Planet's water-carved recesses were sleekly etched into its rocky surface by melting snow or rain.
For evidence, researchers looked toward orographic patterns here on Earth that aren't very alien at all. Namely, Scanlon was inspired by the tropical, sun-soaked big island of Hawaii:
[Hawaii] is home to a quintessential orographic pattern. Moist tropical winds from the east are pushed upward when they hit the mountains of Hawaii's big island. The winds lack the kinetic energy to reach the mountain summit, so they dump their moisture on the eastern side of the island, making parts of it a tropical jungle. The western side, in contrast, is nearly a desert because it sits in a rain shadow cast by the mountain peak. [Brown University]
By comparing this pattern — dry on one side of a mountain peak, wet on the other — to four different mountainous regions on Mars' surface, the research team noted remarkable orographic similarities. Computer model simulations suggest that a similar combination of winds, precipitation, and moisture dumps were once part of the martian climate billions of years ago.
But if Mars' surface possesses similar orographic patterns to a warm paradise like Hawaii...how did the researchers come up with snow? According to Discovery News, the wind model used in the computer simulation suggested a "cold climate at the time of the precipitation, hence the snow fall."
Meaning that once upon a time, one could have feasibly built a snow martian.