OFJ Field Journal from Greg Klotz - 12/13/95
EXPLAINING PHYSICS AND UNSEEN ENGINEERING WORKIt's already been a week since the Galileo Orbiter and Probe performed their flawless activities at Jupiter. What an exciting and historical day. But most of my excitement has subsided.
During Arrival day, I was helping JPL's Public Information Office to provide info to the press and public about the technical aspects of what was happening. Most of the day I hung out in the lab's von Karman auditorium, the headquarters for the press. Many reporters simply wanted to know "what exactly is happening?". I was living in a teacher's paradise! (I have some teaching and speaking experience and I love doing those things, as well as engineering).
I don't know where the day went, but I remember that many people didn't quite understand the exact physics of what was about to happen, and what had already taken place. Some thought that the Probe was released from the Orbiter on December 7th, the same day that it would enter Jupiter's atmosphere (the Probe was actually released last July). Some didn't understand the difference between the Probe and the Orbiter (the Probe goes into the atmosphere, the Orbiter will orbit around Jupiter). Some didn't know that this is just the beginning of a two year tour for the Orbiter in orbit around the great planet, Jupiter! Some just needed to be educated. And educating is my passion!
Some things can be difficult to understand for people with no science background, too. For example, the effects on objects that are not subject to friction (a condition that exists in space) but only move when subject to external forces: gravity, thrusters, solar wind, etc., must be accounted for. And this can only be handled thoroughly with the appropriate mathematics of physical laws and a good computer. Many of the questions I received that day were explained with just a little knowledge of this physics.
One reporter asked me, "What (really) just happened?", referring to the event that marked the first communication from the Probe to the Orbiter after the Probe entered Jupiter's atmosphere. Each of the JPL/Galileo spokespersons used the term 'locking onto the Probe' to describe the event. Well, physically there was no 'locking' in the way that we usually think of locking something up with a key; it's just a way of saying that the Orbiter had established radio communications with the signal from the Probe. Needless to say, I helped the reporter to write a more accurate caption for his photo of project scientist Torrance Johnson jumping up and down with glee.
Throughout all of the day's activities, I sometimes felt a little sad. Possibly this was because I would be leaving the Galileo team soon. I have recently found a new position at JPL, building hardware for some new projects. I have been wanting to get back into the hardware business, actually building equipment that will fly into space someday, much like in the '80s when I was working on several devices used on Galileo. Somehow I will always be able to share in the excitement of Galileo's future discoveries (being that I am still at JPL), but not from the same vantage point.
Finally, the next big event of the day came - Jupiter Orbit Insertion. This event, however, I would spend with a group of friends and family of Galileo team members, including a few friends and family of my own. By the time the moment came to receive indication from the Orbiter that its main engine had started to burn and had burned for the proper length of time to put it into orbit, I had begun to lose my voice from all the previous excitement. My oldest son was there, but I think I was the bigger 'kid' at that moment.
I had spent the last year and a half testing the Probe Relay and Jupiter Orbit Insertion sequence of computer commands that was eventually put into the Orbiter's onboard computer and run at this time. We had seen this sequence 'execute' (or run) in our test facility at least ten times - but now it was for real! And talk about perfect! The accolades from the press, the public, NASA, JPL and our own Project leaders have continued to pour in. Somehow, I just knew that everything would go fine - I really have to hand it to my co-workers who struggled over engineering this sequence to work just right. Especially for the efforts they made to think of ways to handle all the problems that could possibly occur - just in case!
This brings me to one last tidbit that I wanted to relate to everyone about engineering. Towards the end of the evening, after the burn had completed and the Project leaders had taken their bows, there were a group of reporters and TV news writers that asked many questions at the press conference. Bill O'Neil, the project manager, had just indicated that his team of Project engineers had to get going because they had a great deal of work to do. A little earlier, he had also stated that the next time we would receive data from the spacecraft would be on Sunday, December 10th -- 3 days later. One reporter spotted the inconsistency, and asked for an explanation: how is it that the engineers could be so busy that they have to leave now, when the next data doesn't even arrive until Sunday?
Bill explained about some of the activities that will occur over the next few days. But it struck me that this is a typical misunderstanding by the public, the media and others not involved in science and engineering about how a space mission works -- that we only have to do work when the science data comes down.
What really happens is that we can't gather all that science without first doing a LOT of engineering. There's a tremendous amount of work going on "behind the scenes." This is not to say that science is not important (the science people are working just as hard to get ready for their observations), or that science cannot be done without engineering. But, with a project like Galileo, or any other space science mission, the amount of engineering that is required to just *get* the science can be enormous.
What Bill was saying is that he and his team of engineers were going to spend plenty of time in the next few days before the next science data were received, just making engineering decisions. The Project engineers must use the work from other engineers like me to make the final decisions. Nothing really happens until the Project engineers say so - as it should be. But this is still engineering and it is very important to the success of the mission. Without this process of careful review of the recommendations of the engineers at ground-zero, there may not be a Galileo Orbiter acting as a platform for the science instruments. Much, much more goes into delivering good science than simply the receipt, analysis and processing of the data. It is truly a team effort!
I want to say also that I have learned much from working with this team - and I cannot impress strongly enough the importance of team work. I wish the Galileo team that I am leaving, continued success and a willingness to continue to work together.