News and Updates


ASU professor strives to better understand the potential for future eruptions at Yellowstone volcano by studying those in the recent past

We’ve long known that beneath the scenic landscapes of Yellowstone National Park sleeps a supervolcano with a giant chamber of hot, partly molten rock below it.

Though it hasn’t risen from slumber in nearly 70,000 years, many wonder when Yellowstone volcano will awaken and erupt again. According to new research at Arizona State University, there may be a way to predict when that happens.

While geological processes don’t follow a schedule, petrologist Christy Till, a professor in ASU’s School of Earth and Space Exploration, has produced one way to estimate when Yellowstone might erupt again.

“We find that the last time Yellowstone erupted after sitting dormant for a long time, the eruption was triggered within 10 months of new magma moving into the base of the volcano, while other times it erupted closer to the 10 year mark,” says Till.

The new study, published Wednesday in the journal Geology, is based on examinations of the volcano’s distant past combined with advanced microanalytical techniques. Till and her colleagues were the first to use NanoSIMS ion probe measurements to document very sharp chemical concentration gradients in magma crystals, which allow a calculation of the timescale between reheating and eruption for the magma.

This does not mean that Yellowstone will erupt in 10 months, or even 10 years. The countdown clock starts ticking when there is evidence of magma moving into the crust. If that happens, there will be some notice as Yellowstone is monitored by numerous instruments that can detect precursors to eruptions such as earthquake swarms caused by magma moving beneath the surface.

And if history is a good predictor of the future, the next eruption won’t be cataclysmic.

Geologic evidence suggests that Yellowstone has produced three enormous eruptions within the past 2.1 million years, but these are not the only type of eruptions that can occur. Volcanologists say there have been more than 23 smaller eruptions at Yellowstone since the last major eruption approximately 640,000 years ago. The most recent small eruption occurred approximately 70,000 years ago.

If a magma doesn’t erupt, it will sit in the crust and slowly cool, forming crystals. The magma will sit in that state – mostly crystals with a tiny amount of liquid magma – for a very long time. Over thousands of years, the last little bit of this magma will crystallize unless it becomes reheated and reignites another eruption.

For Till and her colleagues, the question was, “How quickly can you reheat a cooled magma chamber and get it to erupt?”

Till collected samples from lava flows and analyzed the crystals in them with the NanoSIMS. The crystals from the magma chamber grow zones like tree rings, which allow a reconstruction of their history and changes in their environment through time.

“Our results suggest an eruption at the beginning of Yellowstone’s most recent volcanic cycle was triggered within 10 months after reheating of a mostly crystallized magma reservoir following a 220,000-year period of volcanic quiescence,” says Till. “A similarly energetic reheating of Yellowstone’s current sub-surface magma bodies could end approximately 70,000 years of volcanic repose and lead to a future eruption over similar timescales.”

Caption: ASU professor Christy Till strives to better understand the potential for future eruptions at Yellowstone volcano by studying those in the recent past. She and paper co-author Jorge Vazquez examine Yellowstone lavas in the field.
Credit: Naomi Thompson

Written by Nikki Cassis



Built from scratch in a lab on ASU's campus, the OSIRIS-REx Thermal Emission Spectrometer is leaving home to join a NASA mission to sample an asteroid.

A journey that will stretch millions of miles and take years to complete begins with a short trip to a loading dock.

The OSIRIS-REx Thermal Emission Spectrometer (OTES for short) is the first space instrument built entirely on the Arizona State University campus. It forms a key part of a NASA mission to collect a sample from a primitive asteroid and return the sample to Earth.

About the size of a microwave oven, OTES has spent the last several years being designed, built, tested, and calibrated. It has been bathed in rays to mimic the Sun's radiation, it has endured temperatures high and low, and it has experienced atmospheric pressures ranging from Earth-normal to hard vacuum.

Now after three months of round-the-clock testing, OTES is shipping out for the solar system.

"We're extremely pleased to have built this outstanding instrument here at ASU," says Philip Christensen, OTES' designer and instrument scientist. "Our weeks of testing and calibration have shown that OTES is of exceptional quality and sensitivity.

"We expect it's the first of many instruments to come from ASU."

Christensen is Regents Professor of Geological Sciences in ASU's School of Earth and Space Exploration. While his main research has involved Mars, Christensen says, "OTES is a direct descendant of two highly successful infrared instruments we've sent to Mars. These have mapped the rocks and minerals on that planet."

He explains, "The infrared is great for identifying minerals, and OTES will map the mineralogy of the asteroid's surface."

OTES is one of five instruments on NASA's OSIRIS-REx mission, and the first to be completed. OSIRIS-REx stands for Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer. The mission is led by the University of Arizona in Tucson, and is the third mission in NASA's New Frontiers solar system exploration program.

The flight plan calls for the OSIRIS-REx spacecraft to launch in September 2016 and rendezvous with asteroid 101955 Bennu in August 2018, with a first sample-collecting attempt in October 2019. Bennu was chosen as a target in part because it is believed to be little changed from the time it formed, early in the solar system's history. Samples from it could improve our understanding of the origin of Earth's water and organics — both essential to life as we know it.

Touch and go

OSIRIS-REx will spend up to 15 months surveying Bennu's mineralogy and chemistry using OTES and another spectrometer working at shorter infrared and visible wavelengths. A visible-light camera suite, a laser altimeter, and an X-ray spectrometer will complete the picture of the asteroid.

When mission scientists have chosen a spot on the asteroid to sample, OSIRIS-REx will approach the surface, touch it briefly, and collect at least 60 grams (2 ounces) of dust, soil, and rubble.

With the sample collected, OSIRIS-REx will cruise back to Earth and use a return capsule to deliver the sample to a landing site in Utah in September 2023. Then after diverting past Earth, the spacecraft will go into orbit around the Sun.

Says Christensen, "After spending most of my career studying Mars, it's exciting and challenging to focus our attention on the origin and history of asteroids and the early solar system."

The School of Earth and Space Exploration is a unit of ASU's College of Liberal Arts and Sciences. 


Long-running NASA Mars Odyssey orbiter has carried ASU Mars camera for 14 years and nearly a billion miles.

Next week, a visual and infrared camera designed at Arizona State University will pass 60,000 orbits of the Red Planet.

It is carried on NASA's Mars Odyssey orbiter, the longest-operating spacecraft from any nation at Mars. Since arriving there, the ASU camera has taken nearly 400,000 images.

 NASA/JPL-Caltech/Arizona State UniversityThe camera – the Thermal Emission Imaging System (THEMIS), which operates in five visual and nine infrared (heat-sensitive) "colors" – was designed by ASU professor Philip Christensen, the instrument's principal investigator.

"Mars Odyssey's enduring success has let THEMIS achieve a longer run of observations than any previous instrument at Mars," says Christensen, Regents Professor of Geological Sciences and the Ed and Helen Korrick Professor in the School of Earth and Space Exploration at ASU.

"THEMIS has thus provided the context for most recent Mars scientific research. We're very grateful to the scientists, engineers, and technicians who have kept the spacecraft in good health."

He adds, "THEMIS also continues a tradition of ASU instruments working at Mars. This began almost 20 years ago, with our Thermal Emission Spectrometer (TES), which flew on NASA's Mars Global Surveyor, operating from 1996 to 2006."

Even today, Christensen says, he uses THEMIS in his class for first-year undergraduate students. He challenges the class to think of a Mars geology problem, and the students then target THEMIS to take images to resolve the question.

"THEMIS brings space exploration directly into their studies at first hand," he says.

As of this week, THEMIS has produced 208,240 images in visible-light wavelengths and 188,760 in thermal-infrared wavelengths. THEMIS images are the basis for detailed global maps and for identification of some surface materials, such as chloride salt deposits and silica-rich terrain. Its infrared imaging also indicates how quickly different parts of the surface cool off at night or warm up in sunlight, which provides information about how dusty or rocky the ground is.

These observations have allowed scientists to map the properties of the surface materials over nearly all of Mars. A particular area of interest is 96-mile-wide Gale Crater, currently the exploration site of the Mars Science Laboratory rover, Curiosity.

Mars Odyssey began orbiting the Red Planet on October 23, 2001. It will complete orbit 60,000 on June 23, 2015.

"The spacecraft is in good health, with all subsystems functional and with enough propellant for about 10 more years," says Mars Odyssey project manager David Lehman of NASA's Jet Propulsion Laboratory.

Besides conducting observations, Odyssey also serves as a crucial communications relay to Earth for the two active rovers, Curiosity and Opportunity, operating on the Martian surface.

Dawn patrol

In 2014, Odyssey began a gradual drift in its orbit designed to begin passing over terrain lit by early morning sunlight rather than afternoon light. In its orbit, the spacecraft always flies near each pole. Its current orbit flies along the "terminator" line between night and day both on the northbound and southbound halves of each circuit. The drift will be halted later this year with a maneuver to lock in the Martian time of day that Odyssey crosses the equator.

The goal of the orbit change is to let THEMIS systematically observe the Martian atmosphere and surface shortly after local sunrise. This is to detect transient atmospheric features such as frosts, fogs, hazes, and clouds that burn off or vanish as the Martian day goes on.

Already, an example of this are the clouds that gather around the upper slopes and in the vast summit pit (caldera) of Pavonis Mons. This is one of the giant volcanoes in the Tharsis area, with a summit that reaches about nine miles above the average radius of Mars, a datum that serves as "sea level."

Christensen says, "Pursuing a 'dawn patrol' with THEMIS gives us hope we can catch in the act and study daily effects, seasonal ones, and even those which we think change from year-to-Martian-year."

The School of Earth and Space Exploration is a unit of ASU's College of Liberal Arts and Sciences.  


Karen Knierman, a Postdoctoral Research Fellow working with professors Chris Groppi and Paul Scowen in ASU’s School of Earth and Space Exploration, received a prestigious National Science Foundation (NSF) Astronomy and Astrophysics Postdoctoral Fellowship (AAPF). The fellowship will fund three years of her research, including stipend and annual research costs, starting June 1, 2015.

Knierman, an extragalactic observational astrophysicist, will focus her research efforts on characterizing star formation in the tidal debris of minor galaxy mergers. This project will provide the first survey of molecular hydrogen in minor mergers.

“Dr. Knierman’s research focuses on understanding how the process of star formation works in very metal poor environments such as the outer reaches of galaxies that are merging, to gain insight into how material collects together and cools to allow the formation of new stellar and planetary systems,” says Scowen, one of her advisors. “Her work uses data from a range of wavelengths to assess the origins and the success of the star formation process. Her choice to bring her NSF postdoctoral award to work at ASU in SESE adds an important facet to the broader study of star formation as a fundamental process within our School.”

Mergers between galaxies of different mass are very common in the universe and may affect the majority of galaxies including our own Milky Way galaxy. The debris produced in these minor mergers is a unique place to study the factors that influence star formation since it is away from the dense centers of the mergers. Due to the lower pressures and densities in the tidal debris, this study probes the lower bounds of where star formation is possible.

“Thanks to the NSF, I will be able to research the edges of parameter space where star formation occurs in these minor mergers,” says Knierman, who received her Ph.D. in astrophysics in 2013.

In addition to the research component, Knierman will be leading a new astronomy outreach initiative, Multicultural Milky Way, that will engage under-served populations in Arizona in learning about stars and galaxies.

Arizona is home to many diverse populations with rich cultural histories such as Mayan, Navajo, and Apache. Linking astronomy practiced by one’s indigenous culture to that of Western astronomy may increase the interest in science. Through multicultural planetarium shows and associated hands-on activities, under-served families will learn how the Milky Way is represented in different cultures and about the science of galaxies.

Written by Nikki Cassis




Evidence of left-handed cosmic magnetic field provides clues for why the universe contains more matter than antimatter

Giant screw-like magnetic fields in space could offer clues to why there is something rather than nothing in the universe.

According to cosmologists, the Big Bang should have produced equal amounts of matter and antimatter that would almost immediately annihilate each other, leaving a universe that was practically empty. Yet, here we are.

But where is the cosmic antimatter?

Tanmay Vachaspati, a physics professor at Arizona State University, and colleagues at ASU, Washington University and Nagoya University, think they have found a clue to this mystery.

They say that a signal in NASA's Fermi Gamma ray Space Telescope data suggests an overwhelming production of matter in the early universe. They detailed their findings in a paper published May 14 in the journal Monthly Notices of the Royal Astronomical Society.
Finding the signal wasn’t an accident.

In 2001, Vachaspati had predicted that the genesis of matter in the very early universe would also generate a `left-handed’ screw-like magnetic field everywhere in space.

“The surprising connection between matter-antimatter asymmetry and left-handed magnetic fields arises from a detailed theoretical study of how particles interact a billionth of a second after the big bang,” he explained.

Later, Vachaspati and his postdoctoral fellow, Hiroyuki Tashiro, showed that the screw-like magnetic field would imprint a spiral pattern in gamma rays emitted from distant supermassive black holes as they propagate through intergalactic space to Earth.

Describing his recent paper with Francesc Ferrer and Wenlei Chen at Washington University, and ASU Cosmology Initiative postdoctoral fellows, Borun Chowdhury and Hiroyuki Tashiro, Vachaspati said:

“We decided to finally test these theoretical ideas with real data, not expecting to see anything. We were blown away when we observed the predicted spiral pattern in gamma ray data taken by the Fermi Telescope. It is breathtaking that our theoretical ideas might actually have played out in the very early universe, and that we are now beginning to see the effects.”

Caption: An artist’s impression of the Fermi Gamma ray Space Telescope (FGST) in orbit. Credit: NASA.

Written by Nikki Cassis



Extreme environments can be found on Earth, in space, and in the depths of the ocean. Dr. Biology and biologist, astronaut, and mountain climber Scott Parazynski sit down and talk about what life is like to explore these environments. Just what are they teaching us about our bodies and how might they hold up on long voyages in space?

Listen to the podcast at:

Read accompanying story at:

Image by the Hubble Heritage Team.



Did dinosaurs roam the Grand Canyon?

Well, the answer depends on who you talk to. And how old they believe the majestic canyon to be.

While the Grand Canyon’s magnificence and its recognition as one of the most famous geological landscapes in the world inspired many geologists to study its formation, there is still much to learn about it.

While it might be fun to imagine scientists and researchers arguing about whether or giant reptiles were hanging around Arizona’s most famous landmark 65 million years ago, this isn’t a debate about dinosaur territories. It’s a question of when the deep walls of the Grand Canyon were eroded by the snaking Colorado River.

Recently two different groups published papers that suggested the Grand Canyon started forming more than 6 million years ago. One group said the canyon had eroded to nearly its current form by 70 million years ago and another said it started eroding 17 million years ago. These papers have caused several different groups to take a closer look at both old and new data sets – including researchers from Arizona State University.

“We are confident the western canyon is younger than 6 million years and is certainly younger than 18 million years,” says Andy Darling, a graduate student in ASU’s School of Earth and Space Exploration. The research is published online in the June 10 issue of the journal Geosphere.

The problem with the assertion is that studying the age of the Grand Canyon isn’t easy.

Measuring time can be tricky when everything you’re studying is eroding away. And the whole region has been eroding for a long time, so not much is left of the landscape that was there when the Grand Canyon started forming. Yet, most people think the Grand Canyon is young – around 6 million years old based on what is preserved.

While many different detective methods exist to gauge the canyon’s age, Darling and his advisor, Kelin Whipple, a professor in ASU’s School of Earth and Space Exploration, decided to see if the shape of the landscape could be used to infer the timing of canyon incision in a different way.

They analyzed the shape of the land and an understanding about how landforms change plus comparisons to other thoroughly dated features in the region – like the Grand Wash Fault and the cliff-band along it.

As Darling put together computer analyses of the landscape, he and Whipple noticed the cliffs that make the edge of the Colorado Plateau (the Grand Wash Cliffs) look different than the cliffs that make the Grand Canyon. The Grand Canyon cliffs are steeper. Looking more closely, the tributary streams that pour into the Colorado River are also steeper than those in the Grand Wash Cliffs.

Many other researchers have shown the fault that formed the Grand Wash Cliffs experienced most of its movement in a long period of fault slip between 18 and 12 million years ago. The west side of the fault has slipped downward a few kilometers, making a hole for sediment eroding from the Grand Wash Cliffs to pile into. As erosion occurs, steep cliffs become more gradual slopes and rivers flatten out over time. But the western Grand Canyon has steeper cliffs and steeper tributary rivers than those along the Grand Wash Cliffs.

“We think this means that the western Grand Canyon is younger and started eroding more recently and at a higher rate than the area of the Grand Wash Cliffs,” Darling explained. In both landscapes, the amount of erosion measured vertically is about the same: but the time taken to do that erosion is different and hence the erosion rates are different.

Using this inference, they evaluated the three previous hypotheses for the age of incision of Western Grand Canyon: 70 million years ago, 17 million years ago or about 6 million years ago.

“Since the canyon seems to be younger than the fault slip, only the most recent 6 million year old incision idea is supported by the topographic and erosion rate data,” Darling said.

Which, if Darling is correct, means we have an answer to our question: “There’s no way dinosaurs overlapped with what we call the Grand Canyon.”

Written by Nikki Cassis

Image by: Rich Rudow


Tracking electrical signals allows researchers to piece together inner-Earth structures and magma flow

Results from new geophysical experiments led by a researcher at Scripps Institution of Oceanography at UC San Diego are helping scientists understand the complex forces unfolding tens of miles below the planet’s surface.

To understand such inner-Earth dynamics, Scripps experimental petrologist Anne Pommier and her colleagues track and measure electrical currents as they travel through rocks and magma. The strength of electrical currents depends strongly on the presence of fluids or melt (magma), and provides important clues about what’s happening as Earth’s tectonic plates shift at the planet’s surface, as well as deeper processes in the mantle within layers known as the lithosphere and asthenosphere.

As described in the June 11 issue of the journal Nature, Pommier and her colleagues conducted innovative two-step experiments that mimic the structure of the interior of the planet. They used deformed partially molten rocks developed by coauthors at the University of Minnesota in high-pressure torsion experiments conducted at temperatures up to 1,300 degrees Celsius (2,372 degrees Fahrenheit) at Arizona State University.

By measuring the electrical properties of these materials at high pressure and temperature conditions in different directions in the samples, the researchers were able to produce an accurate simulation of conditions and dynamics in the upper mantle.

“The main result of this study is that we now understand a bit better of what’s going on between the lithospheric plates and the underlying mantle in the context of when the plates move very fast, producing a lot of localized deformation,” said Pommier, a researcher at with the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics at Scripps.

Pommier was a postdoc at ASU for part of the study then became a UCSD faculty at the end of the study during paper writing process. The experimental work was performed at ASU in the Multi Anvil High Pressure Facility.

In addition to deciphering processes in the upper mantle, the results can lead to a better understanding of other planetary processes, including how volcanoes function and where magma reaches the earth’s surface.

“In the lab we can interpret (electrical) conductivity measurements in terms of how much magma is there, its temperature, storage conditions, and composition,” said Pommier. “This is very important to predict how magma is stored in the earth and how it migrates from the mantle to the surface of the planet to feed volcanoes and mid-ocean ridges. It also helps us understand what the earth is made of in certain locations around the world, as well as the evolution of geological processes that shape the planet’s surface.”
The results were used to develop new models of electrical conductivity, which were then compared with field data (some collected by Scripps researchers) at locations such as below the East Pacific Rise and the Cocos Plate.

“It’s important to understand how the asthenosphere works if we want to understand how the entire planet works,” said Pommier. “The asthenosphere directly underlies the tectonic plates; thus, if we better understand how it works we can place important constraints on the dynamics at the scale of the planet.”

Coauthor Jim Tyburczy, a professor in ASU’s School of Earth and Space Exploration, says this work “is an example of the extraordinary interdisciplinary work performed at ASU – scientists from SESE, Chemistry, Physics, and Materials Science all use this facility.”

Coauthors of the study included Kurt Leinenweber, Edward Garnero, and James Tyburczy of Arizona State University; David Kohlstedt and Chao Qi of the University of Minnesota; and Stephen Mackwell of the Universities Space Research Association.

The study was supported by the National Science Foundation through Cooperative Studies Of The Earth’s Deep Interior and the Consortium for Materials Properties Research in Earth Sciences (COMPRES).

Written by Mario Aguilera


NSF is celebrating the International Year of Light with weekly images and information about NSF-funded light-based research. Its June 5 post centers on the 3D laser map ‘illuminates’ that earthquake faults. ASU's Ramon Arrowsmith contributed to this.

A team of NSF-funded scientists from the United States, Mexico and China used laser-based LiDAR (light detection and ranging) technology to obtain some of the most comprehensive before-and-after pictures of an earthquake zone, using data from the magnitude 7.2 event that struck near Mexicali, Mexico, in April 2010.

The Mexican government had mapped the area with LIDAR prior to the earthquake in 2006.

When the earthquake occurred, Michael Oskin, from the University of California Davis, and Ramon Arrowsmith, at Arizona State University, received NSF rapid-response funding to carry out an immediate aerial survey to compare the results.

Read the full post here

Image credit Michael Oskin et al.,


Michael Pagano, a postdoctoral research fellow at Arizona State University’s School of Earth and Space Exploration, recently wrote an article for Slate titled, "Seeing Stars. He talks about all the wonderfully weird planets out there that probably don't harbor life - and why they are exciting to him. This comes on the heels of recent paper published in the Astrophysical Journal that ruled out the possibility of star Tau Ceti supporting life.

Photo illustration courtesy PHL/UPR Arecibo via Wikimedia Commons



Seeing Stars