Looking for life on Mars — in Chile

ASU scientists make discovery at South American hot springs that could spur revisiting a Red Planet location already explored

November 17, 2016

Two geoscientists at Arizona State University have made a discovery among hot springs in Chile that may spur scientists to revisit a location on Mars explored several years ago by NASA's Spirit rover. The discovery involves fingerlike structures that form in the hot spring deposits by processes that combine biological and non-biological activity. 

The Chilean hot springs are at a place called El Tatio and lie at the edge of the extremely dry Atacama Desert, one of the best "Mars analog" sites on Earth. ASU astrobiologist Jack Farmer studies an outflow colored by microorganisms that flows from the hot springs at El Tatio in Chile. Farmer and ASU planetary scientist Steve Ruff have identified silica structures at El Tatio that formed with the help of microorganisms and which appear nearly identical to silica structures found by the Spirit rover at a site on Mars. Photo by Steve Ruff Download Full Image

Co-authors Steve Ruff and Jack Farmer, of ASU's School of Earth and Space Exploration, report that El Tatio produces silica deposits with structures influenced by living organisms that appear nearly identical to those found eight years ago by Spirit in Gusev Crater on Mars. Their report was recently published by Nature Communications.

The question naturally arises whether what Spirit found on Mars might also have been influenced by life.

"Mars exploration has reached a stage where we can start looking for 'biosignatures'," said lead author Ruff. Biosignatures are naturally occurring traces that indicate the presence of life, either today or in the past.

On Earth fossils are an everyday example of a biosignature of past life. But biosignatures can take more subtle forms such as organic molecules trapped in rocks. Biosignatures can also include physical structures such as compacted mats of microorganisms called stromatolites, found in various environments on Earth.

No lander or rover on Mars has yet detected any fossils. So scientists assume that any Martian biosignature would be small — think microscopic — and difficult to identify, let alone even find, on a planet with as much surface area as all of Earth's land areas.

Roaming the hills

In 2007, NASA's rover Spirit was exploring next to an eroded deposit of volcanic ash dubbed Home Plate in the Columbia Hills of Gusev Crater on Mars.

The rover's right front-wheel motor had failed, and as the rover dragged the stuck wheel like a plow across the ground, it uncovered a rich deposit of pure silica surrounded by outcrops rich in silica. This is a mineral commonly found in hot springs and geysers like those that Yellowstone National Park is famous for.

Ruff was one of the scientists who identified the silica mineral and along with Farmer, published observations supporting a hot spring origin. But the unusual nodular and fingerlike structures of the silica outcrops next to Home Plate were poorly understood.

Looking for similarities

Several years later, Ruff learned about the El Tatio hot springs from a scientific journal. The hot springs are among the highest known active thermal springs on Earth (over 14,000 feet). At night, even in summer, temperatures at El Tatio often drop below freezing, and by day lots of ultraviolet light from the sun comes through the thin, dry air. This makes El Tatio probably the best terrestrial analog for ancient Martian hot springs.

"We went to El Tatio looking for comparisons with the features found by Spirit at Home Plate," said Ruff. "Our results show that the conditions at El Tatio produce silica deposits with characteristics that are among the most Mars-like of any silica deposits on Earth."

These characteristics compare favorably with the Martian Home Plate silica outcrops, Ruff explained. "The fact that microbes play a role in producing the distinctive silica structures at El Tatio raises the possibility that the Martian silica structures formed in a comparable manner — in other words with the help of organisms that were alive at the time."

Next rover

NASA has plans to send a new rover to Mars in 2020. The yet-unnamed rover will be similar in size and power to the Curiosity rover, currently exploring Gale Crater. But the new rover will have more advanced instruments and the ability to collect and cache samples for later retrieval.

So where should the 2020 rover go?

As NASA did with Curiosity, it has held a series of workshops over several years, where Mars scientists present their best case for one landing site or another. At the end of each workshop, candidate sites are ranked according to their fitness in regard to certain qualities. These include geological setting, potential for preserving biosignatures, and quality of returned samples.

Currently the Columbia Hills/Home Plate site in Gusev Crater stands No. 2 on the list of eight candidates. It's second only to an ancient lakebed in Jezero Crater on the northwest edge of Isidis Planitia, an old impact basin. The next site selection workshop is scheduled for February 2017, with plans to cut the list down to a "Final Four."

Although returning to Gusev's Columbia Hills and Home Plate would rule out exploring a completely new area of Mars — which many scientists would like to do — Ruff and Farmer are hopeful that the site's chances are quite good.

"This is a known hydrothermal deposit," said Ruff. "We know exactly where to land and where to go collect samples. And the silica structures found by Spirit meet the definition of a potential biosignature."

Robert Burnham

Science writer, School of Earth and Space Exploration


Caring at heart of PhD student’s research in her work with refugees

November 17, 2016

When Danielle Wofford graduated with her associate degree in nursing, she did what many new grads do: She took an RN job at a local hospital and saved up some money. After five years at the hospital, she decided to shake things up and bought a one-way ticket to Europe.

While in Belgium, she volunteered at local refugee coffee shops and learned about the refugee experience by taking the time to listen to their stories. “That’s when I realized I had something to offer,” she said. “Even if it was just sitting and listening.” Wofford doing community outreach in rural Egypt Danielle Wofford, College of Nursing and Health Innovation doctoral student, doing community outreach in rural Egypt Download Full Image

In those coffee shops, Wofford was introduced to what would become her life’s work.

After four months in Belgium, she worked as a nurse, and then went to Egypt where she volunteered for various health care projects. A friend told her about a cardiothoracic surgeon who was opening a non-profit cardiac hospital in the area that would provide free world-class cardiac care to the underserved — the first of its kind in the region, where all providers and staff would be trained to American Heart Association standards. 

Wofford signed on and stayed with the Magdi Yacoub Heart Foundation in Aswan, Egypt, for three years. 

During that time she assisted in building the cardiac center, participated on the research team that helped elevate health outcomes for heart patients, provided cardiac care for all ages, helped write the care delivery model for the center, reinvented their nursing education, overcame cultural barriers to empower local nurses and established a training center that continues her work today. 

She also put herself through an RN-to-BSN program and taught herself to speak Arabic. 

It was Wofford’s achievements in Egypt, and her commitment to serving vulnerable populations in Africa, Haiti, Eastern Europe and the Middle East, that earned her admission to the College of Nursing and Health Innovation’s BSN-to-PhD program, as well as pre-doctoral fellowships with the Hartford Center of Gerontological Nursing Excellence and the Transdisciplinary Training in Health Disparities Science program, funded by the National Institute of Nursing Research, National Institutes of Health.

“Her enthusiasm for learning and having a positive influence on society, and her unique focus on women’s health among refugee women,” earned her a spot in the PhD program, said Elizabeth Reifsnider, associate dean for research at the College of Nursing and Heath Innovation.

Wofford’s first paper as a doctoral student, “A Conversation with Calamity: Shedding Light on the Plight of Syrian Refugees,” co-authored with two research colleagues and published in the Journal of Health and Human Experience, is based on research that adapts a social ecological model as a framework to assess the Syrian refugee displacement experience.

Wofford analyzed data collected by her partners from multiple countries surrounding Syria and contributed information from her own interviews with refugee families who reside in the displacement zones surrounding Syria.

“The initial project focused on exploring wellness needs for refugees and quickly changed to outlining their displacement experience,” Wofford said. “After collecting and analyzing the data, we were overwhelmed with what we didn’t know about refugees’ daily struggles and changed our research trajectory.”

She learned that refugee women are often alone or with their children as they flee conflict, and many have PTSD and depression. She also discovered that of the 4 million Syrian refugees who have escaped conflict, less than 1 percent go through the lengthy process of entering developed countries. Most flee to nearby Turkey, Lebanon, Iraq, Egypt and Jordan. 

“The average time a refugee is in a camp is 20 years,” Wofford shared. This discovery, and the fact that many refugees never make it to official camps, but are forced instead to find refuge where they can —under bridges or in dumps, prompted her to devote her research to the spaces in between: the displacement zones.

Wofford, who was recently awarded a scholarship by the Jonas Center for Nursing Excellence for her interest in global leadership, is actively building bridges with communities of like-minded people in order to have a greater impact.

In February, she joined nurses from all over the world for the Fourth Annual Middle Eastern Nurses & Partners Uniting in Human Caring conference in Amman, Jordan, hosted by the Watson Caring Science Institute.  She engaged with others on caring science and discussed her research.

Because of her knowledge of the unspoken realities that refugees face throughout the displacement and resettlement process, she was asked to write a position paper, “Equity and Equality of Medical Care for Refugees,” on behalf of the Nurses in the Middle East of the Watson Caring Science Institute.

Her insights also caught the attention of another participant — a nurse educator from New York and mentor with the United Nations, Dr. Holly Shaw, who invited Wofford to New York to present her research as a part of the Nightingale Initiative for Global Health at the UN's Commission on the Status of Women conference the following month.

Wofford spent five days in New York and presented on the last day of a weeks-long UN conference devoted to bringing issues to light that women face around the world. Dr. Jean Watson, the creator of the Theory of Caring Science, and an icon in Wofford’s eyes, was to be honored that afternoon, and was in the audience when Wofford presented her research.

During Watson’s ceremony, Wofford was asked to share what Watson’s theories have meant to her nursing career.

“I spoke about how Dr. Watson’s work impacted me as a nurse and how it will color my work as a future scholar,” she said. “Caring Science is the future of health care and nursing education globally. Love and kindness is the key to health.” 

While she is deep into the second year of her doctoral program, and works part-time as an RN, Wofford looks forward to traveling abroad next month and for the next two summers to continue her research — “sitting and listening” as she would say, to the community, her health care partners and the refugees, this time with funding provided by USAID.

“My ultimate goal is to advance nursing education and research in developing countries by focusing on the health and wellness needs of vulnerable populations,” she said. “I am a nurse at heart.”

Denise Kronsteiner

Director of Strategic Communications, School for the Future of Innovation in Society