IBEX June 2009
The first IBEX sky map is nearing completion as we collect the last couple months' worth of data to fill it in. Operations continue to go well and we have been receiving and archiving 100% of the data generated by the spacecraft - a real feat for any space mission. The science team has begun the hard work of analyzing the science data and trying to understand what the sky maps at various energies are trying to tell us. As promised when we proposed this mission, we plan on publishing the sky maps as part of the first round of scientific papers, hopefully late this summer or early fall - stay tuned, I'll post them on the web as soon as they are published! The picture shows a few of the roughly 400 Southwest Research Institute employees and their family members who attended the opening of the IBEX planetarium show at the Scobee Planetarium, San Antonio College, on Saturday May 30th.
This month I am really pleased to introduce you to the head of IBEX's Flight Dynamics Group, Lisa Policastri, from Applied Defense Solutions, Inc. Lisa and her team have the critical and difficult job of trying to predict IBEX's very high altitude orbit (nearly out to the Moon). One cannot predict this orbit perfectly owing to all of the various forces on the spacecraft, so they are constantly taking all the data from each telemetry pass and using it to improve the predictions for the upcoming ones. If they ever missed it completely for more than few days, IBEX would be lost and we would have to start a big process of trying to find it in the sky. Thanks Lisa for doing such a great job of not losing our spacecraft!!!
For the June 2009 IBEX interview, we continue on the thread to highlight another IBEX team member who plays a large role in operating and handling the IBEX spacecraft. Lisa Policastri, Flight Dynamics Group Lead for the IBEX mission, works with several of the people who have been featured in recent months. How it all ties together is an interesting story!
Lisa grew up in the city of Baltimore and has lived in Maryland her entire life. "My parents' house has been in the family a very long time and my grandfather was actually born in that house. I always thought that was very interesting…because our house is old, my father was always working on something. I loved to be his helper when he was fixing things. This definitely had an influence on me becoming an engineer. Science and math were always my best subjects in school. I was a huge nerd and was in all the science and engineering clubs, even as a kid. Space just seemed so amazing. I even had the Moon Lego set -- maybe it was really my brother's but in my memory it is mine! I even had a girl astronaut Cabbage Patch doll -- I know she's still somewhere at my parents' house.
"The most fabulous thing about growing up in Baltimore was the amount of programs offered in the city public school system. I recommend to students to do what I did: take advantage of the variety of programs and opportunities wherever they are! I was involved in engineering and science after-school programs starting at age 10 and loved it. I also went to the Baltimore Polytechnic Institute - a public high school that had a curriculum focused on engineering.
"It really wasn't until I was sixteen or seventeen until I decided to apply for aerospace engineering for college. I was thinking about architecture or civil engineering for a while, I suppose because it seemed more achievable. But then last minute, I decided to go for the challenge and go down the aerospace path - the 'space' part of the discipline. Since I had never been on an airplane by the time I started college, airplanes and satellites were equally foreign to me, and space seemed the crazier of the two. I wanted to go for it!
"For college, I stayed local and went to the University of Maryland working on a degree in aerospace engineering, mainly concentrating on the astronautical side of the discipline. Some of the classes were so difficult that I thought if I didn't make it through as an engineer, I would become a high school calculus teacher. But I really, honestly always wanted to be an engineer! So I was determined to stick to it and get good grades. I got involved in the co-op program and started my first real job while I was still in school working for the Naval Center for Space Technology at the Naval Research Laboratory in Washington, D.C. I met so many amazing people while at NRL. I literally grew up there, surrounded by fantastic people who have made major achievements in the astrodynamics community. They really influenced my career and I would not be doing what I do today if it wasn't for those guys!"
For the IBEX mission, Lisa is the Flight Dynamics Group Lead. IBEX is in a very unique orbit, where it only comes close to Earth about once a week. At the far point of the orbit, IBEX is around 200,000 miles away from Earth, or about 80% of the distance to the orbit of the Moon. The Flight Dynamics Group has to ensure that the science team can obtain all of their data from the spacecraft during the close-approach times, when it is about 8,000 miles from Earth. In order to do that successfully, the team must have correct and up-to-date information about IBEX's orbit. Says Lisa, "We need to tell the ground stations where to point their antenna dishes to communicate with the spacecraft. And each time the ground stations communicate with IBEX, they are also 'tracking it', producing tracking measurements. I need those measurements in order to improve our orbit knowledge for communicating with IBEX the next time it comes around closest to Earth. The Moon is also constantly pushing and pulling our orbit…and there are so many different pieces to the solution. So that is where my job fits in. It is actually a very fun role to be in, but very intense at the same time. Day to day I am on the phone with Sheral [Wesley; IBEX Monthly Highlights November 2008] from the Mission Operations Center (MOC) so that we always are making sure we do everything we can to keep things right on track and roll with the punches."
Now that IBEX is in its data-gathering mode, the team has settled into a routine of data measurements, spacecraft tracking and control, and communication. Lisa explains, "My job is somewhat routine where my team and I work to process the tracking measurements, work through the issues, get our best orbit solution, and then get ready for the next orbit. IBEX's orbit period is about 7.5 days, total. When it approaches Earth, that time can be at 3 a.m., so sometimes a typical day can start quite early!"
"The absolute best part of my job is the amount of humor I am able to find in some strange behaviors of this spacecraft, and even better is working with a whole group of people who are also able to do the same. Just when we may think we find a new trend, something totally different happens! It is easy to get wrapped up and become very intense. However, some things are just so ridiculous or so strange that you just have to laugh through it. Seriously, I cannot count the number of times that I have been on the phone with our friends Tim [Perry; IBEX Monthly Highlight May 2009] and Sheral at the MOC or with Chelle [Reno; IBEX Monthly Highlight February 2009], and we are catching up on the latest information - and I just bust out laughing. My flight dynamics team is exactly the same, too - we are all equally enthused and sometimes fight over who gets to support the next contact with the spacecraft."
When thinking about challenges she has faced when getting to this point in her career, Lisa is very honest and explains a problem that several of the Monthly Highlights interviewees have encountered: "I had no idea being a woman in this industry would be as challenging as it is. There are so few women that even go to college for aerospace engineering, and then the number of those that graduate with the degree and actually stick with it is far fewer. Really, I have less than a handful of girlfriends who are also aerospace engineers and none of us even live in the same state. None! I do not know how to fix that! I don't even know where one could begin to fix that. And that bothers me. The fact of being a woman and having what I call the 'curse' of looking quite a bit younger than I am has been really hard, but through all of that I have become very tough, if I wasn't tough enough already being a Baltimore city girl. You become even more determined to prove those guys wrong!
"My biggest advice is to say that it is okay to be the nerd in school and to indulge in it. It does not matter where you live. You need to see through your problems and take advantage of all of the great things that are offered to you - wherever they come from."
Outside of work, Lisa is a die-hard Baltimore Orioles baseball fan - just like her mother. She tries to go to about a dozen games each season. She is also an avid follower of the Maryland Terrapin basketball team, attending as many games as possible. She continues, "I am also a member in the American Astronautical Society and I try to attend one or two conferences a year. You always learn new things at these conferences and it's like a mini reunion there, finding out what your colleagues in the industry are involved in from year to year."
What is in Lisa's future? She hopes to continue her spacecraft work, especially for military applications. In the meantime, Lisa is among a small, but extremely dedicated and amazing IBEX team!