Primitive Life on Mars? A Definite Possibility
March 14, 2013
Mars once had an environment that could have been hospitable to microbial life, according to new findings by Curiosity, the most advanced rover to ever reach the red planet. The discovery by the rover, formally known as the Mars Science Laboratory (MSL), was announced by the National Aeronautics and Space Administration (NASA) this week. Since landing on Mars in 2012, Curiosity has added to the evidence from other rovers and space probes that Mars was a very different planet in the distant past than the wasteland we see today.
For its latest activity, Curiosity examined rock samples drilled from an area thought to have been part of a Martian river system at one time. The samples proved to be partially made of a type of clay that suggests conditions similar to those needed for life on Earth. Furthermore, many chemicals identified in the sample are also essential for life, including nitrates and nitrites, two chemicals used for energy by microbes on Earth.
The new findings are significant in that they show Martian water that was nearly neutral, not too acidic and not too alkaline. Earlier samples collected from other regions of the planet had found evidence of water that was less friendly to life. The discovery of nitrates and nitrites also revealed a possible source of energy for developing microbes.
A hole in a rock called "John Klein" is the site of Curiosity's first sample drilling on Mars. The drilling took place on Feb. 8, 2013. The hole is 0.63 inch (1.6 centimeters) in diameter and 2.5 inches (6.4 centimeters) deep. (NASA/JPL-Caltech/MSSS)
Many scientists think that even though the surface of Mars may not have been ideal for life, there is a possibility that life may have developed early in the planet’s history and adapted to living underground.
Additional World Book articles:
- Microbiology
- Probing the Planets (a special report)
- The Search for Water on Mars (a special report)
- Space exploration (2003) (a Back in Time article)
