In Photos: Finding Mars on Earth

Searching for Mars on Earth

Licancabur volcano

(Image credit: Nataliya Hora/

On Mars, the evidence for life could be concealed in rocks that resemble some of Earth's most extreme environments. Scientists from the SETI Institute will spend five years exploring these unusual geologic sites to learn where and how to look for life. Chile's Licancabur volcano, seen here, had a UV index of 43 recorded in 2003. The level is more similar to surface radiation on Mars than typical conditions on Earth.

Lastarria volcano

Lastarria volcano

(Image credit: Matthew Pritchard)

Lastarria volcano in Chile is one of the few places on Earth where molten sulfur freely flows.

Molten sulfur

Lastarria volcano

(Image credit: Matthew Pritchard)

Sulfur surrounds a steaming vent, or fumarole, at Lastarria volcano.

Australia's red rocks


(Image credit: NASA Earth Observatory)

Some of Earth's oldest fossils appear in Western Australia's Pilbara region. Looking for signs of life here could lead scientists to similar rocks on Mars.

Ancient life

Pilbara stromatolite

(Image credit: Paulo Afonso/

A Pilbara stromatolite. The dark bands are fossilized microbes. Layer by layers, mats of microbes trapped and built up rock-like mounds of sediment 3.45 billion years ago.


Sharks Bay stromatolites

(Image credit: Virginia Edgcomb, Woods Hole Oceanographic Institution)

Stromatolites in Sharks Bay, Australia, one of the few places on Earth where these living fossils survive.

Cold and wet

Axel Heiberg Island

(Image credit: NASA Ames Research Center/Chris McKay)

On Axel Heiberg Island in the Canadian Arctic, salty springs flow year-round.

Hardy microbes

Axel Heiberg Island

(Image credit: NASA Ames Research Center/Chris McKay)

Hardy, cold-loving microbes thrive in the cold and west environment, which may mimic conditions on ancient Mars. Here, green cyanobacteria have colonized a rock from Axel Heiberg Island.

The right brew

Grand Prismatic Spring, Yellowstone National Park.

(Image credit: Jim Peaco, National Park Service)

Some scientists think life may have started on Earth at hydrothermal vents in the ocean, where a rich chemical soup spews from the seafloor. THe SETI researchers will test different methods for finding hydrothermal deposits on Mars.

Becky Oskin
Contributing Writer
Becky Oskin covers Earth science, climate change and space, as well as general science topics. Becky was a science reporter at Live Science and The Pasadena Star-News; she has freelanced for New Scientist and the American Institute of Physics. She earned a master's degree in geology from Caltech, a bachelor's degree from Washington State University, and a graduate certificate in science writing from the University of California, Santa Cruz.