The Curiosity rover was designed to assess
whether Mars ever had an environment able to
support small life forms called microbes. In other
words, its mission is to determine the planet's
To try to solve this question, the rover
analyzes samples scooped from the soil and drilled
from rocks. The record of the planet's climate and
geology is essentially "written in the rocks and
soil" -- in their formation, structure, and
chemical composition. The rover's onboard
laboratory will study rocks, soils, and the local
geologic setting in order to detect chemical
building blocks of life (e.g., forms of carbon) on
Mars and will assess what the martian environment
was like in the past.
So far, the rover has not found direct
evidence that life has ever existed on Mars.
But the rover did analyze rock from an ancient
lake on Mars and discovered that it contained
molecules containing carbon and nitrogen that are
useable to lifeforms.
This is not evidence that life existed, but it
may suggest that at one point, the environment on
Mars was capable of sustaining life – which means
that it is worthwhile to keep studying Mars and
looking for signs of past life.
Check out this video link below to see a NASA
scientist talk about the rover’s biggest
accomplishments since it landed on Mars over 3