Jacob Marrocco

 

KINGSTON, R.I. -- Dr. Dawn Cardace has made discoveries on earth that have potential to be out of this world.

 

Dr. Cardace, who is an assistant professor of geosciences at the University of Rhode Island, explained that the microbiological organisms that live in the most uninhabitable places on earth may also be present on other planets, like Mars.

               

Cardace has examined rock formations and exposed pieces of the earth’s mantle for years and has observed numerous examples of microscopic life either miles underwater or on subducted layers underneath the surface. Subduction is when one of earth’s plates is forced below the edge of another, forcing mantle to be exposed.

              

“I was an earth person and it’s interesting to me how that fellowship at NASA broadened my purview,” Cardace said. “I would go to seminars that dealt with people examining organic compounds in space, like interstellar dust particles, and it completely turned my scientific world view a little bit inside out.”

                

The process of discovering these organisms begins with Cardace and her team collecting large samples of rock from sites they visit, such as the Philippines or California.  Upon return to the laboratory, they remove domino-sized chips off the chunk and place them on a polishing wheel. These pieces of rock are shaved down to about 30 microns in thickness, about the width of a human hair, so that they may be placed in a slide and observed on a microscopic scale.

                

She said that one of the major similarities shared between Earth and Mars is a mineral called serpentinite. On Earth, this rock form has shown the ability to sustain life for microbiological organisms and it is currently being explored on Mars for the same reason. The Mars Rover has discovered several examples of serpentinite under the surface.

                

Cardace went further to say some scientists believe that the sulfuric acid clouds on Venus could have the potential to support microbiological life forms of some kind, despite the fact these gases would be highly toxic to creatures like humans and mammals. 

 

Also, satellite photographs taken of the icy moons orbiting Jupiter have shown change over time in the salty oceans under the crust.While the idea of extraterrestrial equivalents to human beings roaming another planet is still highly questionable, the possibility of microbiological life inhabiting other parts of the galaxy is certainly “reasonable.”

                

“I don’t see any compelling reason why there cannot be microbiological activity in the Martian subsurface,” Cardace said. “The surface of Mars is sterile and, depending on the study you believe, several meters below the surface everything is dead. But we look at the groundwater systems and it looks like we could active deep groundwater regimes on Mars as we have on Earth.”

                

Cardace was also fascinated by the idea of microorganisms existing in the pore space of rocks.  The origin of life on Earth, one of the areas of study that drew her into the field of geosciences, could have been through life forming within the tiny holes found in everyday rocks.

 

She said that there is enough space inside of these pores on which cells could build and begin to sustain life.  This could have been the case for areas like the deepest trenches of the oceans and seas, which have little to no contact with the creatures that live under the surface.

 

She and the geosciences department are in the planning stages of constructing a planetary geology seminar to instruct incoming and undergraduate students on the basics of understanding the structure of Earth and what potentially exists beyond this world.

 

“[The seminar] is for people who want to learn more about the planets or even just our solar system, start there,” Cardace exuberantly said. “Don’t even think yet about all those other stars with all those planets orbiting them. We should just stay close to home with what we know best for now.”