A United Launch Alliance (ULA) Atlas-V rocket thundered into the sky Sept. 8, sending a spacecraft on its way to an asteroid and officially beginning the 7-year-long Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) mission. OSIRIS-REx is currently speeding to asteroid Bennu, where it will go into orbit, find an ideal landing site, pick up a sample of regolith, then return that sample back to Earth for further study by scientists. It is hoped the mission can help answer questions about how life on Earth formed, as well as what measures will need to be taken in the future to deflect an asteroid if ever one is found to be on a collision course.
Dr. Humberto Campins, a Professor of Physics and Astronomy at the University of Central Florida, recently gave an educational presentation about the science of the mission at the Orlando Science Center, and then sat down with AmericaSpace to discuss his main contribution: working with the mission’s imaging team. He will also assist in the creation of maps that will be used to select the sampling site.
“OSIRIS-REx is an acronym that was actually put together by the principal investigator of the mission, Dante Lauretta. ‘Origins’ means we will return a pristine sample of a carbonaceous asteroid, which we believe contains a lot of information about how the solar system formed,” said Dr. Campins in his opening remarks.
“Because this type of asteroid has not been subject to any heating, it has a lot of information that has been preserved. We’re going to bring back samples from an asteroid and be able to validate a lot of what we have been inferring about all the asteroids using ground based techniques, or even space based,” added Campins. “We are going to identify resources that can be used for space exploration, including human exploration, of the solar system. Bennu is also a potentially hazardous asteroid. What that means is that it is not threatening earth now, but its orbit could change and it could become an impact hazard here within another 150 years or so. If we need to deflect this asteroid, this mission is going to help us understand how to do that a lot better.”
Asteroid Bennu was chosen as the target because of its proximity to Earth, its size, and its composition. Since asteroids contain so many natural resources—such as water, organics, and precious metals—studying them now is important since they could become crucial support systems for future manned and robotic missions.
Asteroids as primitive as Bennu are rich in carbon, and have not changed remarkably since their original formation 4 billion years ago. They contain organic molecules, volatiles, and amino acids, all of which are key ingredients that could have formed the foundation for the creation of life on Earth.
As Dr. Campins stated: “There are two main justifications for this mission. One of them is the practical one of Bennu being the most potentially hazardous asteroid. The other one is a scientific one, that it is going to tell us a lot about the origin of the solar system, and specifically, about the type of molecules that existed on Earth before life formed. The sample we are going to bring back from Bennu, is likely to tell us a lot about how life formed on Earth and how it may have formed elsewhere. It is also going to enable human exploration – to asteroids and to Mars, and it will help us to develop ways to mine asteroids for space exploration and even to bring some of those materials back.”
The OSIRIS-REx mission has five key science objectives.
- Return and analyze a sample of Bennu’s surface
- Map the asteroid
- Document the sample site
- Measure the orbit deviation caused by non-gravitational forces (the Yarkovsky effect)
- Compare observations at the asteroid to ground-based observations
So why a sample return mission? If we already have meteorites, most of which come from asteroids, why do we have to go out to an asteroid to pick up a sample?
According to Dr. Campins: “There have been two meteorite cases where we have observed the object enter the atmosphere, then recovered the meteorite. In both of those cases, we have determined that 99.9% of the mass that enters the atmosphere is lost. So, when we recover a meteorite, what we pick up is only 0.1% of what entered the atmosphere. Therefore, we don’t know what the 99.9% is. Bringing back samples will tell us – and chances are, the most interesting stuff is in there. Also, if we bring back samples, future scientists will invent new instruments and new techniques with which we can analyze them.”
Two months after the spacecraft gets close enough to Bennu and decreases its speed, a year-long detailed survey will commence so that sites for sample collection can be mapped out. After a site has been picked, the spacecraft’s Touch-And-Go Sample Acquisition Mechanism (TAGSAM) will extend out to the surface of the asteroid where it will make contact with it for five seconds. A sampler head at the end of the arm will shoot out a burst of pure nitrogen gas that will disrupt the regolith, pushing it into a chamber.
During that five-second pick-up, it is anticipated that the spacecraft will gather, at minimum, 60 grams of material, and at maximum, about 5 or 6 pounds. The outside of the TAGSAM will be outfitted with surface contact pads to collect fine-grained material during the time the sample collector is reaching the regolith. Up to three sampling attempts are possible since the instrument contains three bottles of the nitrogen gas.
Dr. Campins, elaborating on how this process will work, stated: “The spacecraft will deploy its mechanical arm with the sampling mechanism at the end. We will approach the surface of the asteroid at minimal horizontal and vertical velocity. During the time we touch that surface for 5 seconds, there is a spring on that mechanical arm that will absorb some of the energy and then push the spacecraft away from the asteroid without having to fire the thrusters. We don’t want to fire those near the surface so we don’t kick up dust that could blind our cameras.”
In March 2021, OSIRIS-REx will begin its 2.5-year-long trip back to Earth to return its haul. The sample will be protected by a return capsule, which will protect it from heat, as it enters the atmosphere and lands back on the ground.
As of Sept. 15, 2016, the OSIRIS-REx spacecraft was performing perfectly and was located about 2 million miles away (3.2 million kilometers), cruising at approximately 12,300 miles per hour (19,800 kilometers per hour) relative to Earth. The star tracker navigational camera on-board proved that it was in fine working order when it snapped its very first image on Sept. 12, 2016. The camera will continue to take pictures of the stars in order to compare them against an on-board catalog, so that the spacecraft navigation system can orient itself.
Also present at the Orlando Science Center, as a featured speaker, was former astronaut Andrew Allen, Shuttle Commander and three-time spaceflight veteran. We caught up with him that evening for a question-and-answer session about his role in this mission. Allen is currently Vice President and General Manager of the Test and Operations Contract (TOSC) at Kennedy Space Center.
AS: What is your history as an astronaut?
- Allen: I was a pilot for two missions. The pilot is like the first officer. I was a shuttle commander for one mission—they trusted me enough to give me the keys!
AS: How could OSIRIS-REx help with future Mars missions?
- Allen: Well, there is a whole lot we don’t understand or know obviously. There is so much we can learn out there and missions like OSIRIS-REx will give us an opportunity to see what’s on some of these asteroids. There is this technology involved in this mission … you have to learn the answer to the question “How do we do this?” It’s not that easy, and you’ll hear more about it from the experts, but it’s not a simple thing, like driving a car to your house. The spacecraft and the asteroid are both moving at very high speeds. You have to learn how to land correctly, then you have to figure out how to land to pick up your samples, and then get back to Earth. And then, this whole time, you have to figure out how to stay in communication, too. And it will be neat to see what they find out there. You know, we hypothesize everything when it comes to space. We just never know what we’re going to find.
AS: What is the work you do? Are you working with the OSIRIS-REx mission?
- Allen: The contract that I’m working on, the contract that I run, yes we did some work with OSIRIS-REx. The company I am with is Jacobs—they are the prime contractor. We do all the ground support to, essentially, get everything off the pad at Kennedy Space Center. We call it ground operations. That includes getting all the pieces of equipment ready that support the equipment that shows up. We also do what we call processing—that means taking whatever the components are and putting them together. Then they are integrated, tested, checked-out, taken to the launch pad, and then you push that magic button that says “Go!”
AS: How do you think the findings from OREX will help us once we do land on Mars?
- Allen: A lot of what OSIRIS-REx will do is give us some stepping stones for getting to Mars. What we may find in the samples of OSIRIS-REx (Hopefully, we land in a good spot where we get some interesting samples!), for example, maybe a metal that we don’t know anything about, or an organism we know nothing about (Probably unlikely, but you never know!). You might even find some of the types of minerals and chemicals that we know exist or that we don’t think actually exist. You have to go back in time and think about what people felt like, back in Jamestown or Plymouth Rock—they didn’t really know what was over the hill, or what was around the bend in the river. We still even have a lot of stuff on Earth we don’t know anything about, but sometimes the science we learn from space will help us with that. Like imaging systems—MRI, CAT scan, x-rays, all those kinds of things—the more you learn about medicine and the human body, the more you realize what you don’t know. And space is … infinitely more than that.
In the past, samples of the moon (Apollo), a comet tail (Stardust), and solar wind (Genesis) have been collected and returned for study. Everything scientists learn from these missions contributes another piece to the greater puzzle of human space exploration, the origins of our existence, and how to protect the future of humanity here on Earth. Whether it is to learn about the building blocks of life or how to deflect an asteroid that is on a trajectory that intersects with our home planet, the importance of studying these bodies in our Solar System cannot be understated.
As Dr. Campins reminded his audience: “About the impact of asteroids on Earth—as individuals, you do not need to lose any sleep over this because the chances of this happening during our lifetimes, are minimal. You do not count on winning the lottery to pay your next month’s rent or mortgage, therefore you should also not worry about an asteroid hitting us during your lifetime. However, large impacts have occurred and unless civilization does something to prevent that next large impact, we will not continue to exist on Earth. As a civilization, this is a very important endeavor.” Proactively educating ourselves is critical to the preservation of the history of the human race and the future of the generations to follow.
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