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Have a blast at ASU space launch party

OSIRIS-REx launch party starts at 3:30 p.m. Thursday on Tempe campus.
OSIRIS-REx thermal emission spectrometer built entirely on campus at ASU.
Asteroid sample will be largest returned from space since the Apollo era.
September 2, 2016

School of Earth and Space Exploration hosts event for unique mission that aims to collect 4 pounds of material from asteriod

A space launch is a carefully choreographed dance, with thousands of players behind the scenes working to fire a rocket into the black void and send back a precious cargo of knowledge.

Next Thursday afternoon will bring a unique opportunity to witness the launch of a spacecraft carrying an instrument built entirely at Arizona State University.

The School of Earth and Space Exploration is hosting a launch viewing party in the Marston Exploration Theater with a live NASA feed from the Kennedy Space Center in Cape Canaveral, Florida. There also will be launch experts on hand and light refreshments.

Jim Bell will provide color commentary during the event. A professor in the School of Earth and Space Exploration, Bell is heavily involved in NASA solar system exploration missions like those of the Mars rovers Spirit, Opportunity and Curiosity.

“If everything is going perfectly, it’s actually pretty routine,” Bell said. “It’ll light up and go and be gone, and be otherwise uneventful, and that’d be great.”

The coastal Florida weather can be an issue, especially in hurricane season.

“People are going to be watching the weather carefully,” he said. “NASA also has to keep watch on what they call range control — boats drifting in near the launch pad and so on.”

People at the Cape readying the rocket, people at the Goddard Space Flight Center in Maryland responsible for the spacecraft, range safety personnel and meteorologists will be in constant contact as the launch nears.

“We’ll hear controllers talking back and forth,” Bell said. “It’s a wonderfully coordinated dance of all these things that have to go just right.”


An engineering mock up of the OSIRIS-REx Thermal Emission Spectrometer (OTES), the first space instrument built entirely on ASU’s Tempe campus, sits near testing equipment. The mirrored spectrometer will measure thermal and spectral properties of an astroid. Photo by Charlie Leight/ASU Now

The spacecraft is the OSIRIS-REx, and the instrument is the OTES, or OSIRIS-REx thermal emission spectrometer.

Phil Christensen, director of the Mars Space Flight Facility in the School of Earth and Space Exploration and Regents' Professor of geological sciences, built the instrument with a team of 26 engineers and scientists.

On the seven-year mission, the spacecraft will travel to a pyramid-size asteroid named Bennu, study it for a year, reach out and grab 4 pounds of material from the surface, return to Earth and drop the sample capsule in the Utah desert.

It will be the first U.S. mission to carry samples from an asteroid back to Earth and the largest sample returned from space since the Apollo era. Asteroids are remnants of the original building blocks of our solar system; they can help us better understand the formation of the solar system more than 4.5 billion years ago. Scientists suspect that asteroids are a source of the water and organic molecules that may have made their way to Earth and other planetary bodies early in their histories.

“An uncontaminated asteroid sample from a known source would enable precise analyses, revolutionizing our understanding of the early solar system, and cannot be duplicated by spacecraft-based instruments or by studying meteorites,” NASA officials said in a press release.

OSIRIS-REx is the third mission in NASA’s New Frontiers Program, medium-size planetary science missions with a cost cap.

The first two New Frontiers missions went beyond low-Earth orbit to far-reaching destinations. New Horizons flew past Pluto in 2015 and is now on its way to a more distant object beyond. Juno entered orbit around Jupiter in July 2016 and has begun science operations there.

“We’re so excited at ASU and the School of Earth and Space Exploration to witness and share the launch of the first complex spaceflight instrument to be designed and built right here on the Tempe campus,” School of Earth and Space Exploration Director Lindy Elkins-Tanton said. “And this is just the first of many upcoming spacecraft launches we expect over the next few years. We love sharing this work with students and our community, and we hope it’s an inspiration that we can develop, design and build instruments here at ASU that are capable of exploring our universe, and eventually, beyond.”

Christensen and members of his team will be at the Kennedy Space Center for the launch.

“We’re all rooting for Phil and his team and wish them the best on this exciting mission,” Bell said. 

OSIRIS-REx Launch Party

When: 3:30-6 p.m. Thursday, Sept. 8.

Where: Interdisciplinary Science & Technology Building IV (ISTB 4), Tempe campus.

Getting there: ISTB 4 is near the intersection of Rural and Terrace Road in Tempe on the east side of campus. This seven-story structure is accessible on foot via Orange Street and McCallister Avenue. If arriving by light rail, exit at the University and Rural Road stop. Parking is available for $3 an hour inside the Rural Road parking structure just east of ISTB 4. From the parking structure, walk west and enter ISTB 4 through the glass doors on the north side of the building. Please note that a parking fee is charged upon exit. There is additional pay parking directly south of ISTB 4 available for $2 an hour. There is an automated payment registration kiosk on the parking lot's west side (the corner near the building).

Details: Find the event listing here. Contact is Stephanee Germaine, 480-727-3583,

Top image: Artist concept of OSIRIS-REx at asteroid Bennu, a remnant from the dawn of the solar system that may hold clues to the origins of life. Image by NASA’s Goddard Space Flight Center/Conceptual Image Lab

Scott Seckel

Reporter , ASU News

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ASU scientists use 'shake and bake' to get ready

Testing includes liquid nitrogen, forceful vibrations that device must endure.
Space mission will explore asteroid in unprecedented detail.
August 26, 2016

To calibrate, researchers put space instrument in vacuum chamber and subject it to extremes

In movies like “Apollo 13” and “The Martian,” there are scenes where there’s a mechanical problem in space and engineers turn to a copy on the ground to fix it.

That copy is called an engineering model, and one has been calibrated for an Arizona State University-built instrument launching to an asteroid next month. “The reason we’re doing it is to improve the flight instrument,” said Dan Pelham, opto/mechanical engineer. “It gives us the opportunity to improve the one that’s in space.”

Called OTES, for OSIRIS-REx thermal emission spectrometer, the device is the first space instrument built entirely on campus at ASU. It will sniff out what types of minerals are on the asteroid, how big particle sizes are and what the temperature is. The information will be vital to mapping and studying the space object called Bennu, before decisions are made on where to pick up samples.

The OSIRIS-REx mission will travel to Bennu, study it for a year, reach out and grab 4 pounds of material from the surface, return to Earth, and drop the sample capsule in the Utah desert.

Scientists think asteroids may contain clues to the origins of life. The small, rocky bodies have never been explored in this level of detail before. No one knows how they form, how they behave or what’s on them.

“No one has ever seen an asteroid like this up close,” said Phil Christensen, project leader, OTES instrument scientist, director of the Mars Space Flight Facility in the School of Earth and Space Exploration, and Regents' Professor of geological sciences. “That’s fun. That’s exploration. That’s exciting.”

“These samples will be studied by scientists for decades,” project engineer Greg Mehall said. “People think (asteroids) are the building blocks of life.”

Bennu is about the size of one of Giza’s smaller pyramids, large enough to be “a region-killer,” said John Hill, a doctoral student working on the calibration. And one of the reasons it was selected for exploration is its relatively high likelihood of hitting Earth late next century — though reported NASA estimates put that chance at less than a tenth of 1 percent. Still, knowing the physical and chemical makeup of the asteroid will be critical to know in the event of what NASA calls an “impact mitigation mission.”

Osiris-REx is a long mission: seven years. It launches Sept. 8 and spends a year orbiting the sun, building up speed to pick up some of Earth’s orbital energy, then slingshots into deep space.

“It’s a two-year cruise,” Mehall said. “Once we get there, we don’t orbit, because there’s no gravity. We sort of maneuver around it ... The mission starts for us at the end of 2019. Then we study the asteroid for a year.”

Once the samples have been collected, Bennu and Earth might not be aligned. The spacecraft may have to wait to leave. NASA hopes it will be able to leave in 2021. It’s another two-year cruise to return to Earth orbit in 2023.

The mission “isn’t a first, but it’ll be the first one to bring something back,” Christensen said. “We’re going to bring back about 4 pounds of material.”

“Absolute calibration is required for the geology at the asteroid,” Mehall said. “When that instrument says it’s 105 Kelvin, it has to be 105 Kelvin.”

That is what the team worked to ensure last week on the Tempe campus. In one of the clean rooms, on the first floor of Interdisciplinary Science and Technology Building IV, they cranked up a large vacuum chamber.

The chamber is little bit smaller than a Volkswagen bus. It repetitively squeaks like a hamster wheel. Liquid nitrogen boils off the top like Hollywood vampire mist.

They put the spectrometer in the vacuum chamber, heat it up, cook off the gunk (the kind of residue that comes off the dashboard of a new car on a hot day and coats the windows), and then switch on the instrument. Aerospace engineers call this process "shake and bake" because it reproduces the vibrations of a rocket launch as well as the extremes of heat and cold that OTES must survive to do its job.

It uses long-wavelength infrared light to map the asteroid's minerals, which will help mission scientists select where to collect samples. ASU is one of only a handful of universities in the U.S. capable of building NASA-certified space instruments.

It was -190 Celsius in the chamber. Outer space is absolute zero, about -271 Celsius.

“That’s space,” Mehall said. “That’s the coldest we can get with liquid nitrogen.”

“When you open that door, you do not want to go in there,” he said. Nitrogen itself is not harmful — Earth’s atmosphere is 80 percent nitrogen — but nitrogen can displace all the oxygen in the room. “People have died at aerospace companies.”

When they calibrate instruments for weeks on end, there are always two people in the room for safety’s sake, around the clock. To dispose of the nitrogen, they simply let it dissipate slowly.

The goal is to engineer something that can’t fail. There’s no way to repair it remotely, and as Christensen said once watching one of his instruments being launched into space, “Man, that sucker’s gone. It’s out of here, and it’s not coming back.”

“In the early stage, you look at the requirements, which is what it needs to do, what sort of science performance it needs to have, and the environment,” Pelham explained. “You select components that have a high likelihood of working in those conditions. Then what we do is what we call screening and qualification testing of all these sub-components: detectors, motors, things like that. We test them rigorously in the environment they have to work in.

"Generally, we look at the lifetime of the instrument on its mission, and we test those elements to twice that. The idea is you can’t eliminate the risk entirely, that you’re going to have a failure on orbit or in space, but you minimize the risk at hand. It’s only one instrument, so if one of those critical components fails, if it stops working, that’s the best we can do. It costs money, it takes time, but that’s what you do for building a space flight instrument.”

OTES cost in the $12 million to $15 million range. It’s considered low cost for this type of mission. “We’re using technology that was designed and built on previous missions,” Pelham said. TES and Mini-TES both went to Mars, and the optical elements thrived in the extremely dusty environment. OTES isn’t a copy of those instruments, but it is a similar design, which means the team didn’t have to spend as much time designing and building from scratch.

“In NASA-speak they call it TRL: technology readiness level,” Pelham said. “When you have a component that’s a TRL-9, that’s considered the best you can do. It’s got time on orbit.”

It’s an exciting mission, because no one knows what they’ll find on Bennu. There’s only one first time.

“I have been to Mars a lot of times, at least with instruments, and it’s actually fun to do something different,” Christensen said. “Part of the excitement of going to Mars the first time was that we had no idea what we were going to find. After you’ve been there a bunch of times you kind of know what you’re looking for and can expect. The beauty of going to this asteroid is we have no idea what we’re going to find. So it’s fun. It’s discovery versus detailed science — just pure discovery.”

Being able to build a NASA flight instrument on campus is great from a convenience standpoint and from an educational standpoint. While the team works away at the calibration, dozens of students gather at the windows and snap photos.

“The first five times we built (instruments) in Santa Barbara, and I spent, on average, 100 days a year sleeping in a hotel room in Santa Barbara, California, away from my family, away from my house, away from my kids, pets, job,” Christensen said. “To not have to travel is goal No. 1. It’s really nice to just stay home. Secondly, being at a university, we always felt if we could do it on campus, it was an incredible opportunity to get students involved. ... I’ll teach the first lecture of my freshmen class with about 150 students, and I’ll probably leave here, take this off, and go in there and say, ‘Hey, you know, I just spent the last hour building an instrument that’s going to go to an asteroid and now I’m going to tell you about it.’”

The OTES team is led by Christensen, deputy instrument scientist Victoria Hamilton of Southwest Research Institute, and Mehall.

How do you choose an asteroid to study? 

There are more than half a million known asteroids in the solar system. Why this one? Here’s how NASA explained it:

The closest asteroids to Earth are those that orbit with a certain distance, about 124 million miles. The most accessible asteroids to reach are within that range and have orbits that don’t veer wildly all over space. When the mission selected an asteroid in 2008, there were about 7,000 in orbit near Earth, but only 192 met the criteria. 

Small asteroids rotate more quickly than large asteroids. On a small one, they spin so fast all the loose material on the surface is flung off into space. A big one (diameter larger than 200 yards) spins slowly enough that a spacecraft can come safely near it and collect a decent sample. This criteria winnowed 192 candidates down to 26.

Asteroids are organized according to their chemical makeup. Primitive asteroids are carbon-rich and haven’t changed very much since they formed about 4 billion years ago. They hold the chemicals that may have led to life on Earth. Of the 26 candidates left, only 12 had a known chemical makeup. Only five of those were primitive and carbon-rich.

Bennu wins the beauty pageant because it comes close to Earth, it’s big, it’s primitive, and it might hit Earth — even if NASA estimates have been reported at a 1 in 2,700 chance.

Top photo: Optical/mechanical engineers Bill O'Donnell (left) and Dan Pelham prepare the platform in the thermal vacuum test chamber for calibrating the engineering model of the OSIRIS-REx Thermal Emission Spectrometer (OTES) on Aug. 12. Photo by Charlie Leight/ASU Now

Scott Seckel

Reporter , ASU News