Million-mile journey to an asteroid begins for ASU-built instrument

June 26, 2015

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. Setting up for final tests The final tests for OTES include measuring with great precision the instrument's optical field of view. Preparing for this are instrument scientist Philip Christensen (left), opto-mechanical engineer Bill O'Donnell (rear, behind OTES) and project engineer Greg Mehall. The lab is one of the "clean rooms," in which hair – including facial hair – must be covered. Photo by: Charles Leight/ASU News Download Full Image

About the size of a microwave oven, OTES has spent the past 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," said 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 said, "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 it 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 sample-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.

Said 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.

Robert Burnham

Science writer, School of Earth and Space Exploration


ASU earns Minerva grant to study terrorists' social-media recruiting power

June 26, 2015

Earlier this week a United Nations panel asked social-media companies such as Twitter and Facebook to respond to how terrorist groups use their networks to spread propaganda or recruit members with increasing success.

As these terrorist groups, such as ISIS or al-Qaeda, evolve their social-media skills, Arizona State University will be part of a team monitoring their advancements and trying to determine how their online actions can be negated. Images can be powerfully persuasive online. Individuals often have multiple heroes reflecting their opinions on diverse issues, and the team funded by the Minerva grant will study these images. Understanding the relationship of these various heroes — which may range from soccer stars to violent or pacifist religious figures or images — may provide a lens into the diffusion of various ideologies. Photo collage created by project researchers; all photos publicly available. Download Full Image

ASU is leading a group project that has been awarded a Minerva grant to study of what types of information go viral online, and what types of actions or responses can halt the spread of viral information.

The Minerva Initiative is a Department of Defense-sponsored, university-based social-science research initiative launched by the secretary of Defense in 2008. It focuses on areas of strategic importance to U.S. national security.

This grant will allow the team, which includes people from the U.S. Military Academy and Britain’s University of Exeter, to study information cascades – trends marked by people ignoring their own knowledge or information in favor of suggestions from other people’s actions – as they relate to the social-media posts of terrorist networks.

“The first phase of the project is we are trying to understand what goes viral. The viral (message) is driven by two things: what type of content and what type of network. The right content and the right types of networks are going to resonate and spread and maybe gain new followers,” said Hasan Davulcu, the project’s principal investigator, and an associate professor in ASU’s Ira A. Fulton School of Engineering and director of ASU’s Cognitive Information Processing Systems Lab.

Once they understand the information cascade, Davulcu said they might be able to determine how to counter the viral messages. But, he clarifies, this study will not include developing content to thwart online terrorism. Rather, the team will be observing what organic information created by social-media users tends to halt terrorists’ viral content. 

“It’s the early detection of what works for them and what works for others opposing them,” Davulcu said.

The team believes images and videos might be some of the more persuasive ways to create partisan passion.

“We are finding pictures to be extremely telling,” Davulcu said. “In fact, we are going to collect tons of photos that circulate online and put them into games so we can figure out what do people understand by the picture.”

These images could be pictures of enemies or adversaries; a photo of Ghandi to illustrate peace; or something as common as a sports star, suggesting action. Studying the use and relationships of these images could provide a lens into the diffusion of various ideologies.

“It is impossible to monitor all of the conversations, so we have to get better at identifying the ones to which we should be paying attention,” said Paulo Shakarian, a team member and director of the Cyber-Scio Intelligent Systems Lab at ASU. “This requires embedding psycho-social models in a logic programming framework that can gather and analyze social networks, specific attributes of individuals and their relationships to others.”

Shakarian understands the issue of terrorism from another perspective, as a former member of the U.S. Army who served two years in Iraq.

“The idea is that if we can understand which of the postings and messages of ISIS have the potential to go viral then we can learn to combat that much better than we do now,” he said.

ASU’s Minerva grant is situated in its Center for the Study of Religion and Conflict, which incubates new research into the complex role of religion in human affairs.

Mark Woodward, associate professor in ASU’s School of Historical, Philosophical and Religious Studies, and Baoxin Li, associate professor of ASU’s School of Computing, Informatics and Decision Systems, are also part of the Minerva team.

This is ASU’s second Minerva grant. The first was awarded in 2009 to study how to strengthen the voices of the Muslim majority who didn’t condone violence.

Davulcu and Woodward were a part of that project, as well. If this second one goes well, there could be more in the future.

“The transdisciplinary environment of ASU has really enabled us to bring together faculty in innovative ways,” said Linell Cady, director of the Center for the Study of Religion and Confict.

“The fact that we have developed two successful Minerva projects is a real testament to the way in which integrating the deep knowledge of the humanities with cutting-edge computer science can produce a whole much greater than the sum of its parts.”