PART 1: Galileo fact of the day
PART 2: ProbeSquash activity: Installment #10
PART 3: Retrieving past copies of updates-jup
PART 4: Radio science brings home the first science data of the orbital tour
PART 5: The big day: before and after
PART 6: Hosting VIPs and a mother who finally understands

Why is Galileo is going to Jupiter when the two Voyagers have already 
been there? The Voyagers were like a quick car trip past the Grand 
Canyon -- drive by, snap a few pictures, check off that you've been there 
and move on. Galileo is like stopping to explore the canyon, walking the 
trails (satellite tour), riding the rapids (Probe mission), and generally 
taking in the full majesty of the place (fields and particles). 

Final installment #10: Preliminary results and wrap-up

Preliminary indications are that NASA's Galileo Jupiter atmospheric 
probe transmitted its data to the Galileo orbiter mothership for 57 
minutes during the probe's suicidal plunge into Jupiter's atmosphere 
on December 7, project officials report.

We'll keep ProbeSquash participants informed about any changes in 
this number as well as any information about what might have 
caused the end of the Probe's transmission.

Many people have written me to request back issues of these messages.
Please note that if you have access to the Web or Gopher, back issues
are readily available without my help at this Internet URL:
gopher://quest.arc.nasa.gov:70/11/interactive-projects/jupiter/journals

If you do not have access to Gopher or Web, I will try to serve your 
requests as best I am able. At the present moment I am a bit 
overwhelmed by Email, so please be patient if you are awaiting a reply.
Yours, Marc 

December 7, 1995
Well, it's 11:30 pm on Thursday, December 7.....what a day!!! I arrived
here at the Lab around 2:00 pm this afternoon. The first thing I hear is
that some reporter is looking to interview me....WOW!!! Anyway, I went
down to Von Karman Auditorium and talked to the gentleman for about 15
minutes. He is writing a story for a radio electronics magazine so Radio
Science would really interest the readers.

We had four big events today: Io Closest Approach, Jupiter Closest
Approach, Probe Relay, and Jupiter Orbit Insertion. All of them were
nearly perfect. Now, the work begins for our Team. Our experiment begins
at 2:02 am and will continue to 8:13 am (PST). Ours will be the FIRST
SCIENCE DATA TO BE RECEIVED IN THE ORBITAL TOUR!!!
(Even before the Probe data...(smile))

One of our colleagues was in charge of bringing in supper for us and she
brought plenty...so we're all sitting around right now feeling like stuffed
piggies.

The first event that will take place (tonight) as we approach our 
experiment is that the Navigation Team will provide us with an update on 
the trajectory. More specifically, the time of ingress. (Ingress is the 
time that the spacecraft slips behind the planet during an occultation.) If 
the time of ingress has shifted by a small amount from what was 
predicted earlier, we'll leave things as they are. If it's greater than a 
minute, we'll think about having the Deep Space Network station make 
some small changes to help correct the predicts (which basically predict 
what the frequency of the spacecraft's radio signal frequency will be at 
any time--useful if you want to pick up the spacecraft's signal).

Making those predict files is a lot of work. We sent one set of predicts 
out to the station on Monday night. Then, we sent another updated set of 
predicts out to the station on Wednesday night. Each time, the Navigation 
Team delivered an updated trajectory file to us and we calculated a set 
of predicts. The DSN Operations (or Ops) personnel also calculated a set 
of predicts on their own. We then compared our predicts with the DSN 
predicts. If the difference between the two predictions of the spacecraft 
radio frequency is less than some small amount (30 Hertz, in this case), 
then the DSN predicts are used during the actual pass. The reason that we 
used two trajectory updates is that we need the best possible predicts 
for the experiment. We can't be too far off from the expected frequency 
or we might miss the signal entirely.

It's now 12:25 am on Friday and we just heard from the Nav Team. The 
difference between the predicts from Wednesday and the update from the 
Nav Team is about 25 seconds so we've decided that we SHOULD NOT 
attempt to compensate for the slightly-in-error predicts. We might be 
off on the exact frequency of the spacecraft's radio signal by about 37 
Hertz, but we think we can absorb that in the bandwidth we're using (the 
bandwidth--the range of radio frequencies over which we will receive 
signals--covers about 2500 Hertz, so even if we're in error by 37 Hertz, 
the signal should still be picked up. ). We'll start getting data in about 
1/2 hour. Wish us luck....

4:00 am Friday 12/8/95
Man!!! It was beautiful!! The occultation happened right on time. The 
spacecraft signal disappeared just as predicted. The equipment 
performed as it should. The station personnel did all the right things at 
the right time. The Ops Engineer faxed us a copy of the spectrum 
(showing the radio frequencies that we were monitoring) and it looks 
great! All the planning we did is paying off. Whew! What a relief. Now I 
have some time to catch a nap before the egress (when the spacecraft 
should come out from behind Jupiter) at 7:00 am.

8:30 am Friday 12/8/95
Everything worked beautifully! We saw the signal pop back up at the time 
predicted and we tracked it to the end. Then, the spacecraft switched 
channels, so we lost the signal at that point, as expected. We are all 
*very* relieved. Plus, it turned out someone from JPL is at the Deep 
Space Network station in Madrid so he will bring back a copy of the data 
and give it to us on Monday, earlier than we expected to get it. Hooray!! 
Now it's time to get some real sleep!

December 5, 1995
This morning I attending a meeting for people assisting visitors this 
Thursday (Jupiter arrival day). 

Unlike Voyager encounters, there won't be pictures from the spacecraft 
that same day. Unlike Space Shuttle missions, there won't be the 
fireworks of a rocket launch. What the visitors will see, as soon as it 
happens, are signals that the Probe has broadcast data from Jupiter's 
clouds and the Orbiter, holding this precious data, has fired its main 
rocket engine to become a Jovian satellite. To everyone involved, this 
means Galileo has arrived and the cheers and clapping to follow will be 
an event in itself.

At the meeting, we learn that as many as 2000 people will be coming to 
JPL for Galileo's big day. Some are VIPs (the NASA Administrator, Dan 
Goldin, is scheduled to come); others are friends and family of Galileo 
personnel. Combined with the JPL employees who may stay a little later 
after work, this should make for a pretty big crowd.

No single facility on Lab can handle everyone. Every large meeting area is 
being pressed into service, including tents. All the activities at JPL are 
being televised through NASA TV so all NASA centers (and people with 
backyard satellite dishes) can watch with us. Finally, every TV crew in 
the Los Angeles area is coming to send their broadcasts around the 
world.  

My responsibilities are to host Galileo family and friends seated in one 
of the Lab's cafeterias. Tables will cleared to provide room for up to 300 
people. There, I am to brief the crowd on what they will see on two large 
TV monitors and narrate events as they happen. As excited as I expect to 
be, it will be a challenge to preserve the calm, professional appearance 
expected of a JPL host. Looking about the room during the meeting, I 
could see that everyone had the same feeling of anticipation.

This will be a new experience for me. During Galileo's launch and Earth 
encounters, I'd been called upon to help out with visitors, but was too 
involved with operations to break free. Now I'm going to be on the 
outside, watching TV monitors showing others do what I used to do. 

I hope they will hear the cheers from my corner of the Laboratory.
 

December 8, 1995
Today is the 8th of December, the day after Galileo's arrival at Jupiter. 
There is so much to write about. Unfortunately, there are many pressing 
obligations to finish before doing the fun stuff. I will eventually provide 
other journal entries describing my day, I promise.

For now, one brief story says it all. In one corner of JPL's main plaza, a 
large black sign shows a map of the solar system. On it are movable 
symbols for the planets and the spacecraft JPL flies. Since Galileo's 
launch six years ago, everyone on Lab watched Galileo's symbol loop 
around the diagram, leaving a dashed-line trail behind it. At first, flybys 
of Venus and Earth bent Galileo's trail and each loop around the Sun grew 
longer and higher. For the past three years, the trail led directly to 
Jupiter. Each day, Galileo's symbol and Jupiter's symbol inched closer and 
closer. 

All the while, the flight team fought problems with Galileo's High-Gain 
Antenna, propulsion system, and tape recorder. On the 7th of December 
the Probe would have to survive intense accelerations, temperatures, and 
pressures before collecting atmospheric data. Hundreds of thousands of 
kilometers above, the Orbiter would have to collect the Probe's weak 
radio signal and perform a long rocket burn to brake into orbit -- while 
its own electronics endure radiation levels that would quickly kill an 
unprotected human. There could be no second chances. Would it all work?

This morning, a glorious Californian Autumn day, someone tacked a small 
sign onto the map. It said, "BINGO!".

December 11, 1995
Well, arrival day came and it was a zoo, just as I anticipated. The first 
thing that happened was that I got here and noticed that everybody was 
dressed up but me! I must not have gotten word that people were going to 
do this. I was wearing black leggings, black Indian-style boots with 
fringe down the back, a black turtleneck, and a black and white sweater. 
One of my friends looked at me and said "Gee Claudia, those boots were 
popular... in the '70's" (which was when I bought them). But I thought it'll 
be OK, I'm just one of the crew, hanging out today.

Then I got nailed. It was about 10:00 am, and I was waiting for a phone 
call from my PI team at the University of Iowa, we were expecting to 
deliver some data with which to test our instruments in the testbed, and 
instead it was a call from Neal Ausman (the mission director) asking if I 
could take his place as a host at one of the VIP gatherings. First of all, I 
have never gotten a call from Neal Ausman! I pick up the phone and it was 
his secretary saying that Neal Ausman was looking for me and would I 
accept his call. At first I thought I must have done something wrong. Why 
else would the mission director, who I normally never interact with 
directly, call me? 

It turned out that I was supposed to be a host from 4:00 to 7:15 pm in the 
Director's (of JPL) Conference Room. This is a conference room that is 
usually only used by the lab's director, so it's not like I go to meetings 
there all the time! I got there at 4:00 pm and opened the door and there 
were two older men sitting at the other end of the conference table. I 
waved to them and told them I was their hostess. I was carrying a bunch 
of stuff that I didn't want to drop; a slide tray full of slides, a stack of 
slippery overheads, a couple of binders, and some video tapes, so I didn't 
focus on who they were, I just supposed they were some VIP's early for 
the session.  

They were VIP's, all right. It was Dan Goldin, the head of NASA and Gene 
Shoemaker, one of the discoverers of Comet Shoemaker-Levy 9, having a 
private meeting. They, of course, looked at me like I was from the planet 
Mars, and Mr. Goldin says, "you're in the wrong room". I cheerfully said 
"Oh no, this is the Director's Conference Room, right? This is the right 
room." I was smiling at them as I tried to stow my stack. Then I noticed 
that it was Goldin and Shoemaker. Mr Goldin says forcefully "would you 
check with the secretary!" I was *so* embarrassed. I just left and went 
away for about 20 minutes. But I knew other people were coming, and 
sure enough, as I found out later, one of my friends came in after me, she 
also ran into Mr. Goldin and Dr. Shoemaker, and another host who was 
supposed to be there did the same thing. We got together this morning 
and laughed about it. What a way to meet the Administrator of NASA!

As far as arrival day itself was concerned, I was pleased that the press 
was so positive about us. I was afraid that they would portray us in a bad 
light, as they usually do with all the problems we have had over the 
years. Instead they protrayed us as "the little spacecraft that could..." 
Every single newspaper did. Everyone seemed so pleased that we had 
demonstrated great technical capability despite everything. This was a 
very big relief to me. There would have been nothing like working for a 
project that was regarded as a national failure.

The best part was that my mother finally connected with what I have 
been devoted to for the past few years. Especially the past 6 months I 
haven't had much time for returning phone calls. I have neglected friends, 
etc, and I've been saying I've been busy with Galileo work. At 
Thanksgiving my family gave me a hard time about being too devoted to 
the job. They said "just tell those people you won't do all that work..." 
Well, my mother must have seen something about in on the Nightly News 
(with Tom Brokaw - she mentioned him specifically) and she said 
"OHHHH. Is that what you do... We're going to learn all these exciting 
things about Jupiter for the first time... This is really exciting..." By that 
time (I was tired) and all I could say was "...great Mom. I'm glad you like 
it."  But I was really happy that she finally understood why it was 
important to me.

And today Bill O'Neil and Neal Ausman walked through the corridors and 
shook everybody's hand. That was really nice. It's better than a 
certificate signed by a handwriting machine. It makes up for some of 
those long nights writing sequences!