Tag: Guest Bloggers

Human in the Loop: The Importance of Humans Conducting Experiments in Space


This week, comments from guest blogger and International Space Station astronaut Peggy Whitson, Ph.D., as she reflects on why it is important to have humans carry out experiments in space.

We do a lot of interesting science on the International Space Station, but the experiments for me that are the most fun are the ones where I get to be more physically involved. Coming from a science background, that is more exciting for me. The InSPACE-2 investigation was actually a lot of fun while on orbit, because it required significant hands on activity to implement the experiment. I had to change the frequency of the electromagnet as it was sending signals and focus the cameras on different views. InSPACE-2 uses an electromagnetic field surrounding a suspension of iron particles in a liquid. Once you add the electromagnetic field, the solution can actually stiffen and form a solid or semisolid structure. This is good for potential applications as shock absorbers for suspension bridges, buildings, etc.

 

 
Expedition 16 Commander Peggy Whitson works with the InSPACE-2
(Investigating the Structure of Paramagnetic Aggregates from Colloidial
Emulsions-2) experiment in the Microgravity Science Glovebox (MSG)
in the U.S. Laboratory/Destiny. (NASA Image: ISS016E021067)

 

On one occasion, because I have old eyes, I was supposed to set the electromagnet to 20 Hz, but I did not see the decimal point and set it to 2.0 Hz. The experiment was testing a theory regarding the lack of gravity to see if there were any differences compared to ground studies. Since I set up the magnetic field strengths differently than the investigators on the ground had planned, we saw some unusual patterns in the structure. It pulsated, forming moving solid strings. This was interesting for the investigators on the ground, because they had not seen this result at 2 Hz previously. After the investigator told me this, I thought we had to look into things further. Anything that they did not see on the ground that we saw in orbit was of interest in understanding the theories and how these colloidal suspensions work.

After we finished our studies at 20 Hz, we went back and repeated the series at 2 Hz, based on the observed unusual differences. I volunteered some of my weekend time to go back and do this, as I enjoyed the hands on aspect of the experiment. For me, as a scientist, this was really satisfying. I think a lot of scientific discoveries are made as a result of the “I wonder why that happened,” rather than the explicit planned results you might have expected. So even though I screwed something up, it was something that the investigators learned from. The fact that I made an error was what enhanced the investigation.

 

 

This type of happy accident can be true in laboratories on Earth, too. Robotically you can perform the planned procedure, but you are not going to necessarily notice any unplanned consequences. Not that humans are always the cause of the unanticipated discoveries, but more interaction can result in different observations or directions that you may take. Observations from a direct crew perspective may not necessarily be noted by investigators on the ground, too, so this is a great way to show crewmember involvement. The more astronauts understand about the objectives of an investigation, the more they can help with those identifications.

There are lots of different payloads that do not work as expected once on orbit, requiring crew interactions; software may need reloaded or hardware jiggled. For instance, in my first flight, I was changing samples out for the Microencapsulation Electrostatic Processing System (MEPS) experiment, which required a huge amount of effort, so much so that I thought I would break it. I think some of the tolerances were not right, and we got the investigation completed only because of extra effort and some brute force. In fact, on the last sample they told me to push as hard as possible to get it in. Had this been done mechanically, you would not necessarily have been able to apply the extra force to complete the experiment and get all the data sets back to the investigators on the ground. There are just little things that do not work in an investigation the way you anticipate.

The Advanced Diagnostic Ultrasound in Microgravity (ADUM) was another favorite investigation of mine that required human interaction. This study looked at whether you could take an untrained crewmember and guide them with ground support and live downlink. The goal was to see if astronauts could obtain viable images for investigators of various different organs; very useful for remote location medical emergencies. This was fun and enabled great interaction with the ground. It was very hands on to manipulate the ultrasound to show the right image for the investigators to see and determine if the images were usable for identification purposes. On Earth, people are now using these techniques to do ultrasounds in remote locations, from the Arctic Circle to athletic arenas.

Being a researcher on the ground has also given me insight about how important it is to be able to actually modify and change your experiment in real time, based on the results you are getting. The human-in-the-loop element gives us that same capability on the International Space Station.

Dr. Peggy Whitson is the Chief of the Astronaut Office and also served as Expedition 5 flight engineer and Expedition 16 commander. She holds a doctorate in biochemistry from Rice University. In today’s blog Dr. Whitson shares her thoughts and experiences as a crewmember and scientist aboard the International Space Station with the readers of A Lab Aloft.

Of Fish, Astronauts, and Bone Health on Earth

This week, comments from guest blogger Dr. Scott M. Smith as he reflects on recent space station research, which connects a diet rich in fish intake and omega-3 fatty acids to a reduced rate of bone loss.

Scientists spend a lot of time discussing their work in proposals, manuscripts, and meetings, but Eureka! or light-bulb-going-off moments are amazingly rare. Our Nutritional Biochemistry Lab at NASA Johnson Space Center, however, was fortunate enough to have one of these moments recently.

Our lab’s Eureka! moment actually started a few years ago when we submitted a proposal to look at omega-3 fatty acids as a countermeasure for the muscle loss caused by space flight. Omega-3 fatty acids have been shown to help stop muscle loss in cancer patients; we believed the sub-cellular mechanisms of the two types of muscle loss are similar. In theory, if it works for cancer, it should work for space travelers. Although that proposal was well scored, funding was short that year and our experiment did not make the cut.

 

NASA Johnson Space Center Nutritional
Biochemistry Lab Logo

    Image courtesy of NASA

 

The data suggesting that omega-3 fatty acids would help slow or stop muscle loss was pretty convincing, but some softer evidence hinted that omega-3 fatty acids might also help slow bone loss. We proceeded to do a cell culture study—long story short, we added omega-3 fatty acids to bone cells and it suppressed the activation of cells that break down bone; bone breakdown is the process that is accelerated during spaceflight and during disuse here on Earth. This was pretty exciting in and of itself, but not the moment of epiphany.

The Eureka! came when we were in a meeting reviewing another bone loss countermeasure that was tested during bed rest. Unfortunately, despite high hopes going into the study, this method was not working. As I rolled this around in my head, it seemed to me that nothing to date had worked at slowing bone loss. We had tried exercise and other physical countermeasures with limited success and, although drugs are available, there is not a drug out there without side effects.

It was during this reflection that the light bulb went on. Eureka! I realized that our bed rest studies had included a menu that was pretty loaded with fish, which is a great source of omega-3 fatty acids. This was done to help increase the vitamin D content of the diet, a very important factor. As I thought of ways to investigate my hypothesis, I realized I had some challenges to face in gaining specific data on omega-3 fatty acid intake. It is not easy to find volunteers to literally spend a few months in bed, let alone subjects who are willing to participate in the bed rest and also forego eating fish.

Driving home that night, I called my colleague Dr. Sara Zwart and suggested we look at the omega-3 fatty acid intake in the existing bed rest subjects and compare it to the bone data from the same subjects. The next morning, Sara had the graph, which clearly showed a relationship between omega-3 fatty acids and N-telopeptide—a marker of bone breakdown that appears in the urine. Specifically, and statistically significantly, the more omega-3 fatty acids the subjects ate, the less bone breakdown marker they excreted, which was pretty cool!

We then took the next logical step, to see if the diet of astronauts was related to their bone breakdown. We track dietary intake of astronauts during space flight using a food frequency questionnaire or FFQ. This tool monitors the intake of seven key nutrients: energy, fluid, protein, calcium, iron, sodium, potassium. The FFQ is designed to measure only these specific things, so if we wanted to measure anything else, we would typically have to modify how we grouped the foods in the questionnaire.

Instead of redesigning the tool, we took a leap and looked at fish intake in the diet of the International Space Station crewmembers. Given that we did not have the detailed omega-3 fatty acid content of all space station foods, and given that we did not sort out the fish by those rich or poor in omega-3 fatty acid content, this was admittedly a stretch. When we compared the relationship between reported fish intake in crewmembers and their bone loss after flight, however, we found another significant relationship. Those who ate more fish lost less bone. This was awesome stuff! It was one of those rare times in a scientist’s career when unrelated pieces of information actually built into a complete story.

This story did not end, though, with these findings. What we had at this stage was what is called correlational evidence. The two factors—fish intake and bone loss—were related. This does not directly prove a causal relationship, however, and could be nothing more than coincidence or indirect effect. For example, those who ate more fish probably ate less meat, which we also conjecture is bad for bone health. What we need now is a controlled study, where we track and control intakes throughout a space mission, with one group eating a high omega-3 fatty acid diet and others consuming a low or “control” omega-3 diet. By comparing the data from such a study, we can detect differences in bone loss. We have submitted this proposal and hope an opportunity arises in the near future to carry out the experiment.

This research not only has clear benefits for astronauts, but also significant implications for those of us on Earth. These types of relationships—between fish and bone—have been observed. Given the much slower rate of bone loss on Earth, however, makes effects more difficult to pinpoint. Microgravity research can amplify the impacts, providing new knowledge that may benefit those suffering from bone loss. This is just another example of where the space station provides an out-of-this-world platform for human research!

 

Astronaut Suni Williams eats a meal that includes salmon, a fish rich in omega-3 fatty acids,
while on orbit aboard the International Space Station.

Image courtesy of NASA: ISS014E13728

 

Dr. Scott Smith and his colleague Dr. Sara Zwart lead NASA’s Nutritional Biochemistry Lab at Johnson Space Center. The research discussed above was published in the Journal of Bone and Mineral Research (Volume 25, pages 1,049-57, 2010). In addition to ground-research studies, they lead two space station experiments: Nutritional Status Assessment and Pro K, which investigate the roles of animal protein and potassium in mitigating bone loss. In today’s blog Dr. Smith shares his thoughts and experiences as a scientist with the readers of A Lab Aloft.

A Teacher’s View of the International Space Station

This week, comments from guest blogger Susan Mayo with observations about the value of the International Space Station in inspiring students.

As a former high school chemistry and physics teacher, I am pleasantly surprised by the focus on education linked to research in space. For example, I was just at the American Society for Gravitational and Space Biology (ASGSB) annual meeting in Washington, D.C. This gathering included a hands-on workshop and panel geared towards education and I was inspired by the positive, exciting, next-generation focus of this group of professionals. The ASGSB meeting is the first conference I have been to in a long time where they planned to build partnerships with classroom teachers, rather than trying to “fix” them as educators. This, in turn, better enables those teachers to share their knowledge and enthusiasm with their students.

Inspiring the next generation of innovators is an essential component of K-12 education. Children can truly aspire to be anything they want to be if, and only if, they are willing to work for it. Educators have a responsibility to provide students with the tools to guide them through the difficult process of determining where their skills and interests will lead them in the future. Students do not understand the importance of having a strong background in math and science as they progress through their education. With the nationwide focus on testing students to determine knowledge, rather than developing critical thinking skills, we are forcing an entire generation of students to concentrate on becoming test takers and not innovators.

This is where partnerships between industry and educators can truly initiate a difference via collaboration. Well over 31 million students worldwide participated in hands-on activities related to space station research from 2000 to 2006. Now, in 2010, as the International Space Station moves to assembly complete and full utilization, the opportunities for reaching the next generation grow radically.

The new technological developments and scientific research taking place on station are not only cutting edge, but also applicable to our everyday lives. Many of the future careers our students will seize do not even exist today. Educators and students have a unique opportunity with the space station to participate in science while it is happening, rather than teaching about it later on as a history lesson. While speaking at the conference, former astronaut and explorer Dr. Scott Parazynski, Challenger Center for Space Science Education, stated, “NASA is in the business of taking the impossible and making it look easy.” I believe this is what educators do every day in the classroom.

The space station gives teachers an amazing forum for their students. If you are an educator or student who wants to be part of some of our ongoing outreach programs, like EarthKAM, Kids in Micro-g, or the Zero Robotics Challenge, just click on the imbedded links here.

Susan Mayo is a scientist and educator specialist for the International Space Station Office of the Program Scientist. Her background includes experience as a high school chemistry and physics teacher in Idaho and a scientist with a background in biochemistry, chemistry, waste management and environmental science. In today’s blog she shares her thoughts and experiences from the 2010 American Society for Gravitational and Space Biology conference with the readers of A Lab Aloft.