Ken Murphy / 3:06 am March 20th, 2010

Howdy all! I just wanted to post a little something about this year’s winner of the Intel Science Talent Search, who has become my new space hero.

Erika DeBenedictis, a senior at the Albuquerque Academy is doing research on what are variously known as low-energy trajectories, weak stability-boundary trajectories, InterPlanetary Superhighway trajectories, and more esoteric things along those lines. This is a relatively new way of looking at things like spacecraft trajectories in interplanetary space, made possible only by our much increased heft in computing capabilities and advances in the mathematical sciences, especially in things like chaos theory and fractals (also made possible by increased computing heft).

So her work is pretty complicated stuff. I know this because I stumbled upon the concept back in my early days of space interest. The year was 1999, or maybe 2000. I was sick of the financial shenanigans on Wall Street (I was credit analyst on the Wall Street Desk at BNP at the time), and wanted to see if I could break into a new field, one that was exciting and high-tech. I had gone to the UNISPACE III conference in Vienna that summer to serve in the Space Generation Forum, and had learned about International Space University. I was impressed with the caliber of the folks I met who were alumni of ISU, and was itching for a Masters degree. I didn’t want an MBA, because everyone and their dog has an MBA. Maybe a Master of Space Studies?

I joined the New York Space Society to learn more, as NSS seemed most broadly behind the idea of humans in space, something that was definitely a new, 21st Century industry that could lead to greater U.S. economic prosperity. It turned out that the chapter president was totally hot, which was definitely encouraging. One of our meetings was at a Mars-themed restaurant on the West Side called Mars 2112, and one of the folks who showed up was Ed Belbruno from Princeton. He introduced us to the concept of how the warps and folds created in 3-D space by gravity masses can alter how we perceive spacecraft trajectories.

The key concept is that at certain places in space a small change in trajectory can lead to big changes in where you end up. Sort of like if you’re on a surfboard near the top of a wave. Small changes in where you point the tip are going to have a big effect on where you end up on the beach.

This concept lay dormant while I learned traditional orbital mechanics at ISU, but it was at my internship at Boeing’s Human Space Flight & Exploration (HSF&E) division, while I was working on my Master’s Independent Project on Cislunar Infrastructure Architectures, that I stumbled upon the idea again, and realized its importance in relation to the Lagrange points, especially the Earth-Moon L-1. A number of the papers I used are filed away over in the EML-1 section of the Lunar Library. When I made my presentation to the folks supervising me during my internship it wasn’t anything they hadn’t seen before, so I got some tough questions, but I think they were surprised that it was coming from someone who was effectively a complete outsider in the space field. I feel somewhat vindicated that the NASA Exploration Team (NExT) came to the same conclusion, as I learned on a NASA Academy field trip in 2002 where we got a briefing from one of the NExT guys. I was just sitting there flabbergasted as they presented EML-1 as a key strategic target in cislunar space.

In essence, these trajectories allow you to trade time for fuel. Fuel budgets for spacecraft that use these curves of space are measured in tens of meters per second of delta-V, or change in velocity. People are used to thinking in terms of kilometers per second of delta-V, so the comparison is something akin to the Shuttle’s OMS units as compared with the SMEs. Less fuel payload translates into more science payload, so this is a good thing.

This is not your daddy’s Hohmann trajectory

When coupled with what we’ve learned from the Hubble telescope and other attempts at human structures in space, it is possible to conceive of a network of robotic spacecraft (s/c) stationed around the Solar system providing ongoing data. When it’s time for an upgrade, once the replacement arrives on station the s/c gets kicked onto the interplanetary superhighway for a long journey back to near-Earth space. Once it arrives near the EML-1 point a tug goes out and ferries it back to the L-1 station. There crews service an ongoing stream of returning craft, adding new instrumentation, giving them a once over, and topping off the tank. Once the s/c is ready it gets kicked back onto the Interplanetary Superhighways to head back out to its station. Just in time for the replacement to come home for its service check.

One might ask what useful services these s/c could perform scattered at the various Lagrange points around the Solar system? The science fiction novel “The Venus Equilateral” proposed that a station crewed by super-engineers be placed at one of the Sun-Venus Lagrange points to provide communication with Mars when it’s on the other side of the Sun from the Earth. A probe positioned at the Sun-Mars L-1 could serve as the foundation for an eventual facility there to serve as a logistics point for the Mars system (i.e. including Phobos and Deimos) as well as the Asteroid Belt beyond. Of course, a s/c at Sun-Mars L-2 could help keep an eye on the Asteroid Belt, while one placed at each of the Sun-Jupiter and Sun-Saturn L-2s could keep an eye on the Kuiper Belt and Oort Cloud. An earlier-warning system, so to speak.

“Peace on Lagrange” by Hop David

So by tapping into these weak gravitational stability boundaries and the trajectories that can make use of them, we can significantly upgrade our science capabilities by providing ongoing upgrades to our tools instead of just throwing them into the void. That is the fundamental lesson of the Hubble telescope. By Hubble-izing our probes we can enable a much more robust and ongoing collection of data from around the Solar system, including earlier awareness of stuff drifting in from the nether regions.

Plus it would provide jobs for some of the engineers and techs at the EML-1 station. That goes towards making a case that we should have a crewed facility there.

The thing is, figuring out these trajectories is not easy. I realized early on that I should have paid more attention during the matrices section of calculus class back in high school, as the Euler transformations just did me in. I just don’t have strong calculus-fu, which is probably why I’m a banker and not an engineer.

And that’s why this young lady is my new space hero(ine). I can understand the concepts mapped out in the displays behind her in the picture at the MSNBC article linked above, and even explain them somewhat, I just can’t do the math that proves them. She can. Excelsior, Erika! Excelsior!

So do your math, kiddos, and think about space studies. $100,000 is nothing to sneeze at. It pays for a whole lot of college.