A Taste of Weightlessness

Recently, senior physics major Lisa Lee had an opportunity to conduct a medical technology experiment aboard NASA's reduced gravity aircraft at Johnson Space Center's Ellington Field in Houston, Texas. Sometimes referred to as the "vomit comet," the plane performs a series of dives, giving those onboard periods of weightlessness for up to 25 seconds at a time. Lee teamed up with students from Stanford University and proposed an experiment, which was selected by the Reduced Gravity Education Flight Program from more than 55 submitted proposals.

Lee received support from the George W. Housner Student Discovery Fund, which is designed to enhance the academic experience of undergrads at Caltech. The fund covered Lee's portion of the materials for the experiment as well as her travel and hotel expenses.

We asked Lee to fill us in on her unique experience and how it relates to other activities in which she has participated at Caltech.

So how was your microgravity experience?

It was awesome and really strange. It was almost like swimming, but not really. I didn't get that heart-in-your-stomach feeling that you sometimes get on roller coasters. You just kind of start floating. You don't know which way is up and which way is down. I was doing flips, but I couldn't even tell.

Can you talk about the experiment you conducted on the microgravity plane?

The background here is that astronauts experience a lot of medical complications in space because there's no gravity, so there's a need to constantly monitor how they're doing. But a lot of current monitoring technology is very bulky, and there's a very steep learning curve to learning how to use it. But there's a device called a hemodynamic transesophageal echocardiogram (hTEE) that people are starting to use for real-time cardiac monitoring in intensive care units. It's a little ultrasound probe that you thread down a patient's throat, and it can image your heart.

This hTEE is very easy to learn how to use, it's small, and it's portable. So the goal of our experiment was to see if it worked well in zero gravity with the idea that astronauts could bring it up to the ISS [International Space Station], say, and it would provide this easier way to monitor heart conditions.

We used a high-quality mannequin with a simulated esophagus and a plastic heart to image. The probe was connected to a monitor above the mannequin's head, so we could see the ultrasound images. We looked at two things: the kind of images that we could get and the actual intubation process.

And what did you find?

When we compared our ground results with our flight results, it looked very good. In fact, the images looked the same. But we're also having our results analyzed by professional doctors to see if they can see subtleties that we can't.

So this isn't exactly what you're researching on campus, right?

Right, I'm a physics major, but I work in applied physics. Currently I'm studying how surface-tension forces affect spreading on thin films. I took a nanofabrication class, APh 109, and found that I really enjoy the wet lab work. Before that, I had done a lot of computational stuff. I worked at SLAC [the Stanford Linear Accelerator Center] for a summer, and I worked at CERN [the European Organization for Nuclear Research] for a summer, too. It was all really fun, but it was a lot of programming and analyzing data.

The lab class was different. The work was hands-on. You had to put on a lab coat and gloves; it was a lot of making your own chips. Last summer, I did a SURF [Summer Undergraduate Research Fellowship] working on the hydrodynamics of thin films, and I continued through the school year.

Now that you're preparing to graduate, what plans do you have for the future?

I'm going to study applied physics at Harvard. Eventually I'd like to go into industry. I like doing work and seeing it affect people quickly, and I think the products you design in industry, as opposed to academia, are more geared toward helping people immediately.

That ties in with your microgravity project, which has clear medical applications.

Yes, I'm hoping that my work in applied physics will shift toward more medical areas. I felt like this project was kind of geared toward where I'd like to go because it is medical, but it is also a strong application of physics.

And the Housner Fund played a role in allowing you to participate?

Yes, the Housner Fund is basically a fund for students to go do activities—other scholarly activities. I very much appreciated their support, and I encourage other students to apply for it. When I was at CERN a couple of summers ago, the fund also allowed me to attend a nuclear physics conference in Romania, which was very nice.

What other activities do you participate in on campus?

I've played volleyball all four years, which is a lot of fun because I didn't actually play before I got here. This year I got to start. I had only played a little bit in elementary school, but the sports culture here very much encourages walking on.

I also played the French horn in the band for my first couple years here. Freshmen year, we got to go to China and played on the Great Wall.

It sounds like you have had a number of outstanding experiences during your four years here. What is your favorite thing about Caltech?

The ratio of students to faculty. For me, personally, sometimes I would learn things in class or I would read something on the Internet like a Physical Review Letter, and be like 'Oh, wow! This is really cool, but I don't understand it.' So I would just walk into a professor's office and say, 'Hey can you talk about this with me?' And every single professor would say, 'Oh yeah, sure. Sit down. Let's talk about it.' They would talk sometimes for a couple of hours. So all of the professors are very accessible, and they're eager to help us learn.

One final question that we just have to ask: Did you get sick on the microgravity plane?

[laughing] No. There were others on the flight who got sick, but I didn't feel sick at all.