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OFJ97 Field Journal from Marcia Segura - 3/18/97

[Editor's Note: Marcia is a science coordinator on the Galileo Near Infrared Mapping Spectrometer science team.]

Time certainly does fly!!!

Much has happened since November of 1995 and I want to share with you some of the events of 1996. It was an incredible year filled with anticipation, excitement, and discovery as well as some anxiety and pain.

All that software testing in 1995 paid off in 1996 with the return of the first orbit data. It was during that time, we discovered that the Near Infrared Mapping Spectrometer (NIMS - my favorite instrument) had experienced an anomaly (that's the word we use when something unexpected or unpredicted happens). Our instrument software STOPPED. It froze up much like your PC when you open one too many applications. Much of the first orbit Io and Jupiter NIMS data was lost. This was not an OOPS (should have known better/minor) anomaly but an OHMIGOD (this is critical/major/a lot of work) anomaly. Would this or could this happen again? Is the instrument gone? Was Galileo's capability to study surface composition lost? If the instrument wasn't lost, could we get a work- around or a fix ready before the next orbit (which was little over a month away)? Those were some of the questions that went thru my mind at the time. ANXIETY, WORRY, and STRESS!!!

Well, in true Galileo and NIMS style, after 3 intense weeks of analysis and creativity, an explanation and a plan emerged. The explanation: the instrument didn't take kindly to Jupiter's radiation environment. In fact, when NIMS got tired of the radiation build-up, the software would stop functioning. Armed with a plausible explanation and the knowledge that NIMS would be exposed to radiation on every orbit without fail, we needed to protect the science data. So the plan: the instrument software would be reloaded or restarted numerous times throughout the encounter period (7 days) to counteract the radiation effects on the software. And yes, we did use this plan for orbit 2. And orbit 3 and orbit 6. And every other orbit we'll do, too.

The first orbit gave me some anxiety but also gave the first NIMS view of Callisto, my favorite Jovian moon. I was really excited to finally see Callisto data even though the observation was distant and filled with booms (in the picture of the spacecraft, you can spot them easily. NIMS can see them as well). Within the NIMS team, I get teased terribly about my fondness for Callisto and the favorite comment about this observation was something only a mother could love. But... it revealed secrets about surface composition that we are still puzzling over and whetted our appetite for more.

[You can see some of the NIMS Callisto observations at http://www.jpl.nasa.gov/galileo/callisto/021897.html and

There has been no relaxing since.. An encounter comes and we monitor the instrument for signs of software halts. This information must be factored into the data playback plans so we use our precious return bits wisely. In between encounters, plans for future observations continue and data returns every day. As you can see, there is a lot going on behind the scenes.

On a more personal note, 1996 was so busy at work, that the guys and I didn't make the trip back east to Maine last summer. Adrian, my oldest son (birthday last week - now 20), decided not to make the trip because he was working. Matthew, who is 11, attended the day camp and played in the summer basketball league, decided he couldn't miss a field trip or a game. Needless to say, the choice not to make the trip became the only option.

But. in early September, I did manage to sneak away to Salt Lake City for 2 days plus a weekend to do some genealogy research (one of my interests away from work). It was then that I found out about my mother's diagnosis of terminal cancer. I returned to Los Angeles briefly and left again for the East Coast. My mother's condition/care required close monitoring so she gave up her apartment and her independence. My sister Nola and I spent time helping her sort through her belongings and packing. I didn't realize it but she saved EVERYTHING!!! Old movie ticket stubs, pens that didn't work, Christmas wrapping paper, partial decks of cards, mason jars with no lids, etc. We spent a lot of time sifting through old photographs which while nostalgic and sad, did provide an element of fun, laughter, enjoyment, and a happy memory.

The festive Christmas decorations and tree didn't appear in the Segura household until December 23rd and it was well into the night before the job was done. The good news is that I did complete all my shopping before Christmas Eve and I didn't have to use Fed-Ex overnight for package delivery. This was an improvement from 1995 to be sure!

Signing off for now. Hoping that 1997 brings you all your heart desires and more.



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