The Curiosity Rover Picked Up Souvenirs From the Red Planet

Samples From the Surface Give Insight into Mars' Microbial History

by Masha Vodyanik, age 16

Curiosity, NASA’s most advanced rover yet, landed on Mars in August 2012 and continues to survey the planet today. The car-sized rover weighs a ton and contains cutting-edge technology, enabling it to explore Mars’ rocky terrains. Since its landing, the rover has harvested stunning photographs and evidence that points to the existence of microbial life.

UW Green Bay researcher Aileen Yingst is one of the main scientists in charge of this operation. Yingst built the Mars Handlens Imager, the high tech camera on the rover that takes photos at 12 micrometers per pixel. In comparison, a strand of human hair is 80 micrometers across. At that scale, even grains of sand can be clearly seen. The camera is critical in determining what the surface rocks of Mars are made of.

According to Yingst, the mission’s landing was equivalent to the Apollo landings in terms of difficulty. To land safely, the rover flew into Mars’ atmosphere like a bird, instead of dropping like a rock. In addition, for the landing to be fully successful, the rover had just seven minutes to slow down from 13,200 to 1.7 miles per hour before it landed. This crucial time period was referred to as the “seven minutes of terror.”

The landing site of Curiosity was the inside of Gale Crater. The crater has a history of water. Investigating it provides scientists information on an environment favorable for microbial life. Besides looking for water, the rover checks for other energy necessary for life. It tests the atmosphere to see if it contains radiation or other factors that could be potentially hazardous.

Right next to the landing site is a mountain informally named Mount Sharp. The rover’s final destination was on the slope of that mountain. On the way to its final point, the rover, using a robotic arm, takes rock and soil samples from Mars’ terrain. These samples are then tested for their chemical and mineral composition. Chemical composition can be determined using a laser beam that reads an emitted spark’s spectrum of light.

Eventually, after a long and careful drilling operation, Curiosity collected a tablespoon of crushed interior rocks. This was the very first sample acquired from the interior of Mars. The sample was taken from Yellowknife Bay – an ancient riverbed with a history of water.

Yellowknife Bay is made up of large bedrocks with veins containing different minerals. Most of the rocks deposited in these veins are siltstone or mudstone; both could be potentially deposited by water.

Results from the first drilling suggest the ancient environments of Mars were potentially microbe-friendly. Months after the discovery, the rover drilled a follow-up hole into the rock, nine feet from the first drilling. Scientists hope to confirm the data found from their very first interior sample. Finding out what these Mars rocks are made of gives clues about the planet’s history and its ability to host plant life.