To trace the volatile elements that form the atmospheres of planets, NASA’s Astrobiology Program awarded a five-year, $5-million grant to an interdisciplinary consortium, including researchers at the University of Â鶹´«Ã½. The award will help establish a scientific foundation for detecting the signatures of life on other worlds.

The research targets elements and molecules such as nitrogen, water, carbon dioxide, ammonia, hydrogen and methane that are often found in planetary atmospheres. These are commonly called “volatiles,” and many are essential to the development of life.

The team is led by Natalie Batalha at the University of California Santa Cruz (UCSC), and is one of eight new research teams selected by NASA to inaugurate its Interdisciplinary Consortia for Astrobiology Research (ICAR) program. The UH collaborators are Eric Gaidos in the , Bin Chen, Elena Dobrica and Gary Huss in the , and Dan Huber and Jonathan Williams at the . In addition to UH and UCSC, the consortium includes researchers at the University of Colorado at Boulder, University of Kansas and NASA Ames Research Center.

“My UH colleagues and I look forward to contributing to this multi-disciplinary investigation that will answer two big questions. First, how did the Earth get its volatile elements, and, second, can we find habitable planets with similar volatiles around other stars?” explained UH Mānoa astrobiologist Gaidos.

The research will include observations of the formation of planetary systems and habitable planets around other stars, as well as laboratory research on volatiles in the solar system.

Gaidos added, “Here in Â鶹´«Ã½ we are fortunate to have at our disposal both telescopes to observe distant planet-hosting stars, and microscopes to study meteorites and samples returned from space. These, and laboratory experiments to simulate the processes affecting volatiles, are crucial pieces of this puzzle.”

Potentially habitable worlds

A recent analysis of data from NASA’s highly successful Kepler Mission, which discovered more than 2,500 exoplanets, suggests there are at least 300 million potentially habitable worlds in our galaxy. But Batalha noted that a planet in the “habitable zone” of its star (where liquid water could pool on the planet’s surface) does not necessarily have all the conditions needed for life.

“There may be planets with liquid water on the surface that are dead,” said Batalha, who served as Kepler project scientist. “One of the messages from the Kepler Mission was that the diversity of exoplanets far exceeds the diversity of our own solar system. If we want to understand the diversity of rocky planets in habitable zones, we have to study the physical processes that sculpt them.”

‘Following the volatiles’

For this team, that means “following the volatiles,” tracing the path of the volatile elements such as carbon and oxygen that make up a planet’s atmosphere. That path goes from star-forming clouds into protoplanetary disks, to the building blocks of planets, and eventually into the planets themselves, where volatile elements can move between the surface, atmosphere and interior, and even be lost to space.

The researchers will address four fundamental questions: What is the inventory of volatiles in planetary building blocks? Where do volatiles come from, and where do they go? How are volatiles distributed between a planet’s interior, surface and atmosphere? And what can atmospheric observations tell us about the volatile inventories and chemistries of exoplanets?

The launch of the James Webb Space Telescope (JWST) in 2021 will usher in a new era of exoplanet exploration and the characterization of exoplanet atmospheres. The consortium will develop the tools needed to interpret observations of exoplanet atmospheres made by JWST and the latest generation of ground-based telescopes.

A long-standing mystery involving floods or “jökulhlaups” that emerge suddenly and unpredictably from glaciers or ice caps was serendipitously solved by a team led by astrobiologist and Earth scientist Eric Gaidos. The findings were published in .

This mystery occurs in Iceland where volcanic heat melts glacial ice and the water accumulates in lakes underneath the glaciers. Scientists have long studied the development of these floods, which are some of the largest on Earth.

“These floods may affect the motion of some glaciers and are a significant hazard in Iceland,” said Gaidos, a professor at UH ²Ñā²Ô´Ç²¹â€™s (SOEST). “But the mechanism and timing of the initiation of these floods have not been understood.”

Then, in June 2015, an unexpected series of events revealed how these floods start.

That summer, Gaidos and colleagues drilled a hole to one of the Icelandic lakes to study its microbial life. While collecting samples through the borehole, the team noticed a downwards current, like a bathtub drain, in the hole.

“The flow was so strong we nearly lost our sensors and sampling equipment into the hole,” said Gaidos. “We surmised that we had accidentally connected a water mass inside the glacier to the lake beneath. That water mass was rapidly draining into the lake.”

A few days later, after the team had left the glacier, the lake drained in a flood. Fortunately, the flood was small and Icelanders have an elaborate early-warning system that monitors their rivers so no people were hurt, nor infrastructure damaged in this event.

The researchers used a computer model of the draining of the flow through the hole, and its effect on the lake, to show that this could have triggered the flood.

“We discovered that the glacier can contain smaller bodies of water above the lakes fed by summer melting,” said Gaidos. “If this water body is hydraulically connected to the lake then the pressure in the lake rises and that allows water to start draining out underneath the glacier.”

For more see .

Rebecca Prescott, a microbiology student who recently received her PhD, has won a prestigious award for her project, “Survival in extreme environments through cooperation: biofilms and looking for life on Mars,” under the program Broadening Participation of Groups Underrepresented in Biology.

“We are interested in how cooperative behavior, through chemical communication in bacteria, may help microbes survive in extreme environments that are representative of early Earth and early Mars,” said Prescott.

Is cooperation key to survival in harsh places, like Mars?

In the field of astrobiology, determining the range of planetary conditions that are favorable for life, detecting life on other planets and understanding how life evolved on Earth are all important questions, and further exploration of the Universe. To address these questions, Prescott is focusing on how biofilms from hypersaline ponds in San Salvador Island in the Bahamas and lava caves on Â鶹´«Ã½ Island may survive through cooperative behavior and chemical communication, referred to as quorum sensing.

Prescott is working at the University of Edinburgh, using the Planetary Environmental Liquid Simulator, to evaluate the genomic changes of hypersaline biofilm mats from the Bahamas and Hawaiian lava caves when placed in early Mars and early Earth conditions. She is also evaluating whether molecules used by bacteria to communicate may be preserved in rocks for long periods of time, which will help find new ways to detect life on other planets.

“To help us understand where microbial life may occur on Mars or other planets, past or present, we must understand how microbial communities evolve and function in extreme environments as a group, rather than single species,” said Prescott. “Quorum sensing gives us a peek into the interactive world of bacteria and how cooperation may be key to survival in harsh environments.”

Quorum sensing has not been investigated in the field of astrobiology, so this study will be the first to illuminate how microbial interactions might influence survival in early Mars and early Earth conditions.

Her fellowship is funded by the National Science Foundation’s Division of Biological Infrastructure and the Tribal Colleges and Universities Program. Prescott worked under the guidance of , microbiology associate professor and committee chair, while working on her PhD at UH.

Discovering common cultural values through astrobiology

Prescott is conducting research and training that is increasing the participation of groups underrepresented in biology under the mentorship of two sponsoring scientists: , University of South Carolina, and , University of Edinburgh. The questions of how life evolved on Earth are imbedded in cultural traditions across the globe, and the highly interdisciplinary field of astrobiology provides unique opportunities to develop and integrate indigenous cultural perspectives into K–12 classrooms.

Prescott also works with the Summer Teacher Academy, and with science teachers in Â鶹´«Ã½ and the Carolinas, Eastern Band of Cherokee Indians, to develop teacher training workshops in culture-based science of astrobiology and genomic data science.

Intrigued by the quest to discover life on Mars, student researcher Nicolette Thomas has come up with a way to set parameters when looking for signs of microbial populations. In her work, she’s testing lava from different areas of Â鶹´«Ã½ Island for DNA.

Thomas is a junior double majoring in astronomy/astrophysics and biology while conducting research as . Her mentor is John Hamilton, an instructor with the at UH Hilo since 2003.

After a summer internship with Hamilton at the , Thomas became inspired by the BASALT grant and wrote a research proposal, which she presented to The Space Grant Consortium.

“She is doing graduate student work as an undergraduate,” said Hamilton.

Thomas is interested in the Red Planet and says, “I want to look at places on Earth that are similar to Mars, and Â鶹´«Ã½ is the one that I work with because it’s chemically identical to Mars.”

Because of this similarity, Â鶹´«Ã½ is considered a top analog site for Mars research. Thomas explains that the Hawaiian lava is made up of the same components as the Mars regolith (layer of rocky material) and it is on the regolith that researchers can look for biosignatures and environmental alterations. The existence of either of those things could signal the presence of life, or also the past existence of it.

Recent Pāhoa lava flow may provide clues about search for life on Mars

The recent Pāhoa lava flow presented an opportunity for Thomas who, with Hamilton’s knowledge, was able to gain access to and take samples of basalt. She then analyzed them in a lab using DNA extraction and polymerase chain reaction, which is used to amplify trace amounts of DNA and in some instances RNA. These traces can later be sequenced to determine the identity of the source.

In her research, Thomas is looking at pioneer species of organisms that first arrive on lava flows, and then is using those findings to set an upper limit on biomass expectations for scientists searching for life on Mars.

Thomas would like to conduct DNA sequencing next. “It’s interesting to find out what [the source of the DNA] is, and you can get rid of the things that are probably contamination,” she says. “Then you can constrain the limits even more.”

The sequencing would help Thomas set the best parameters allowing for identification of microbes and archaea, which include different forms of extremophiles (a type of life that survives in radically severe conditions) that some scientists expect might be found on Mars.

For more on Thomas read the .

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Nader Haghighipour, an astronomer at the and the at the has been elected president of Division F (planetary systems and astrobiology) of the (IAU) for 2015–18. Haghighipour will have an important role in promoting and encouraging the study of planetary systems around our sun and outside our solar system, as well as the search for life in the universe, one of the most vital fields of astronomy today.

In the last 20 years, nearly 2,000 exoplanets have been discovered and that number will continue to grow rapidly. Several of these planets are potentially capable of harboring life.

In addition, there have been numerous space missions to bodies within our solar system that have greatly increased our knowledge of these relatively close worlds. Two have recently been in the news: , which flew by Pluto and its moons and , which has been exploring Comet 67P/Churyumov-Gerasimenko.

Haghighipour at forefront of search for habitable planets

Haghighipour’s research interests include the formation, detection and dynamical evolution of extrasolar planets (especially potentially habitable ones), planets in binary star systems, the origin of Earth’s water and astrobiology. He edited the volume , and more recently, , the proceedings of an IAU symposium held in Beijing in 2012.

In 2012 he received a Humboldt Research Fellowship award, which he used to spend 2013–14 in Germany at the in Heidelberg and the University of Tuebingen.

Division F promotes studies of planetary systems

Division F deals with our solar system, extrasolar planetary systems and astrobiology. It promotes studies of planetary systems, including our own, aimed at the understanding of their formation and evolution, from the point of view of the dynamics and of the physics, as well as of the occurrence of conditions favorable to the development of life in the universe. It also promotes the dissemination of reliable physical and dynamical data about astronomical objects in our solar system and other planetary systems and oversees the assignment of proper nomenclature and discovery credits, where appropriate.

The IAU will be holding its triennial at the Honolulu Convention Center August 3–14. More than 2,500 astronomers from 75 countries are expected to attend.

—By Louise Good

Researchers at the University of Â鶹´«Ã½ at Mānoa’s have provided compelling evidence that glycerol, a key molecule in the origin of Earth’s living organisms, may have occurred in space more than 4 billion years ago. Glycerol represents the central building block in cells—the smallest structural and biological unit of all known living organisms on Earth.

The newly published research paper was authored by Professor Ralf Kaiser, Postdoc Surajit Maity and Assistant Researcher Brant M. Jones of the at UH Mānoa. The research details the methods used to re-create in a laboratory how glycerol could have been formed in astrophysically relevant ices by ionizing radiation in interstellar space and carried by meteorites and comets to Earth prior to the existence of life.

In an ultra-high vacuum chamber cooled down to 5 degrees above absolute zero (5 Kelvin), the Â鶹´«Ã½ team simulated icy “sand grains” coated with an alcohol—methanol. When zapped with high-energy electrons to simulate the cosmic rays in space, methanol reacted to form complex, organic compounds—specifically glycerol.

“Our hope and expectation is to propel astrobiologically related research involving the search for the molecular origin of life in our universe to the next level, ultimately leading to the production of an inventory of biorelevant molecules, which could have seeded the evolution of life as we know it,” the authors wrote. This work challenges an alternative theory that glycerol and other prebiotic cell components were synthesized on Earth under hydrothermal conditions. “This requires cutting edge tunable lasers and vacuum ultraviolet light to probe the newly formed molecules,” Kaiser and Jones added.

The researchers expect to define a benchmark for future sampling of distinct classes of astrobiologically relevant molecules like sugars, sugar alcohols and sugar acids. They hope to re-create nucleotides in the laboratory in next generation scattering experiments simulating conditions in the harsh environment of space. Nucleotides are a key components of ribonucleic acid implicated in the replication of living organisms.