OFJ Field Journal from Greg Klotz - 12/13/95
EXPLAINING PHYSICS AND UNSEEN ENGINEERING WORK
It'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.
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