PART 1: Galileo fact of the day
PART 2: I'm ecstatic
PART 3: Sucker interviews and Mommy's broken spacecraft
PART 4: Following dreams
PART 5: Final exam day
PART 6: Snippets from the WebChat
PART 7: A wonderful moment: the Probe Press Release

Typical home insulation has a rating R=19, and is 4" thick. Galileo's 
insulating blankets are 3 times as effective, and 1/20th the 
thickness (2/10ths of an inch thick). The spacecraft insulation is 65 
times "better" than the fiberglass insulation that you'll find in your 
home! 

December 7, 1995  9:06 p.m.
I'm ecstatic.  The day has been perfect.  After 16 years of work, this 
is the crowning glory. We now have a permanent satellite of Jupiter, 
sent by Mankind to study the giant planet. I almost cried as the 
insertion burn terminated perfectly. I am profoundly grateful that I 
had the chance to help achieve this.

We have a little bit of cleanup work (all expected) to do before we 
go home, so this has to be short. More journals will be forthcoming 
later, but now I think I want to savor this moment briefly, and then 
begin thinking about the beginning of a new challenge. The new 
challenge is to keep our satellite busy for two years, bringing forth 
new discoveries.

December 7, 1995
Arrival Day started out for me with a 3:30 AM "sucker" interview for 
a tv station in the Midwest (why am I calling it a "sucker" 
interview?  Well, pretty much because you have to be a sucker in 
order to agree to wake up at 3:30 AM to do it :-).  I pushed the sleep 
out of my eyes and talked about Galileo for a few minutes for the 
benefit of early morning commuters. I wonder if they could tell
that this member of the Galileo flight team wasn't seated at a 
computer terminal, but was lounging at the breakfast table in a 
bathrobe.

All morning, I kept thinking about where the spacecraft was at that 
particular moment. While I was driving along the freeway to the lab, 
Galileo was crossing Europa's orbit. Sitting at my desk, I could 
glance at my computer screen and see from the Galileo web site an 
image showing that the spacecraft was flying by Io.

After a busy morning, I grabbed a Diet Coke and some pretzels and 
sat down with a group of coworkers to watch the NASA TV coverage.  
By 3 PM Pacific time, more and more people were trickling in to 
wait for the announcement about the probe--had the orbiter managed 
to "lock up" on the probe signal? The minutes dragged on. The 
earliest time where we could hear for the probe came and went. No 
word. On the tv screen, the project managers could be seen standing 
in their conference room, frowning, arms crossed. Still no word.  I 
was suddenly gripped by doubt--were we really going to fail at this 
point?

And then the managers flung their arms up in the air, and we knew 
that the probe was alive and well and communicating with the 
orbiter. The data was going to be there--this amazing idea of hurling 
something at Jupiter at over 100,000 miles per hour was actually 
going to work out.  We'd cleared one big hurdle. There was one more 
to come.

For the Jupiter Orbit Insertion burn, the do-or-die maneuver that 
would either put Galileo into orbit around Jupiter or else leave it on 
a flyby trajectory, the project  was going to be hosting 1,500 
expected guests--friends, family, NASA and local government 
officials, reporters, JPL retirees, and so forth. I and a couple dozen 
of my fellow flight team members were hosts. We'd been told to 
dress "appropriately," which for many of us meant to dress in a way 
that bore no resemblance to our normal workday attire.  It's not that 
people here are slobs--it's just that this is a great place to work if 
you'd rather wear jeans and a t-shirt to work instead of a business 
suit.

And so that evening, we watched the data trace that told us that the 
burn had started--and, nearly 50 minutes later, we watched the burn 
end. We clapped, an cheered, and breathed a sigh of relief.

There was one other, personal, highlight of my day. The local free 
weekly paper had a story on Galileo that quoted the Project manager, 
a few members of the science teams--and my two and a half year 
old daughter. Under the subheading "Mommy's spacecraft is broken," 
the text reads in part "When the recorder's tape slipped on October 
11, Pitesky went home worried that the entire mission would be 
jeopardized. She explained to her two-year-old daughter, Shana, "The 
tape recorder on mommy's spacecraft is broken." This made a strong 
impact on Shana, who repeated it to friends for weeks afterward."

Probe data safely aboard, orbiter safely in orbit, and my daughter's 
first newspaper quote--after 11 years of working on Galileo, what 
more could I ask for?

December 7, 1995
Today is the Big Day and everyone has been asking me how I feel. It 
has been a very long journey for Galileo but also for myself. I've 
taken a moment to recall how I got here, how I worked for so many 
years to be part of this. Ever since I was a little girl, growing up in 
Rio de Janeiro, Brazil, I wanted to work for NASA and be involved in 
the exploration of space. I don't know how I got the idea in my head, 
but it's been there for the longest time. So, I left Brazil at the age of 
18, to go to University in London, England. I had realized during my 
teens that if I stayed in my home country I was very unlikely to be 
able to achieve my dream.

So, off to England I went, to get a degree in Astronomy, then a Ph.D. 
in planetary geology. I got involved in the study of volcanoes and was 
hooked. Volcanoes are just great and seeing an eruption live is one of 
the most exciting things that anyone can do. Just as I started my 
Ph.D., the Voyager spacecraft flew by Jupiter and found out that 
there are active volcanoes on Io, spewing out stuff over 100 miles 
above the ground. Wow!

So, I lived in England for 14 years, swore allegiance to the Queen, 
became a citizen and thought I would live there ever after but... Well, 
funding for planetary research was very bad and I still had this 
dream of being involved in space exploration, be a member of a real 
space mission. A chance phone conversation with a JPL scientist led 
me to apply for a postdoctoral research position here. It was a 
temporary job, only two years. People in England thought I was crazy 
to leave my secure civil-service job as a museum curator but I knew 
I had to follow my dream. So off I went, moving countries once more.

I was lucky at JPL. I became good friends with Adriana Ocampo, 
another South American. She was working on Galileo as a science 
coordinator for the Near Infrared Mapping Spectrometer (NIMS) team 
and as it turned out, NIMS needed someone to plan Io (one of Jupiter's 
moons) science. That's how I joined the project, in 1991. My first job 
was to plan the science observations for Galileo's second Earth-Moon 
flyby, which took place in 1992. Then I started to plan Io science. I 
went to many meetings and had to fight many battles. The loss of the 
high gain antenna meant that our resources were limited, so all the 
instrument teams were in fierce competition. This competition was 
particularly severe for the Io flyby which took place today. We 
discussed, we met in many places, we negotiated, compromised, and 
at last came up with a really good plan. We finished that plan at the 
end of 1993 - just as my son was born. I took 10 days off work to 
have the baby and I can really say that he was born between 
meetings. This last October, about the time I celebrated his second 
birthday, we found out about the problem with the tape recorder. A 
couple of weeks later we knew that we would not be recording any Io 
flyby data. SO, all that planning and work and high expectations came 
to nothing.

I have to admit to feeling a little bitter about the loss, but I'm still 
celebrating. I know we will have two years of gathering really good 
data, for Io, Jupiter, and the other satellites. There is a lot to look 
forward to and we should not dwell on failures. You really have to be 
philosophical when you work on a space mission, you know that 
everything is at the forefront of technology and something can go 
wrong. You have to risk working for a long time on something that 
may come to nothing. But I have no regrets and I will be very happy 
when we get into orbit tonight. It will be the start of two exciting 
years, when we should find out many of Io's secrets. There is still 
the hope that we will go back to Io for a close look - maybe at the 
end of the mission or with another mission. In fact, I'm already 
involved in the planning of a possible next mission to Io. Will it get 
funded? I don't know, but I know I have to try. The dream must go on.

December 7, 1995
Final exam day!  At least, that is how it feels.   In a way, I've been 
waiting for this day for more than 17 years.  I started working on 
Galileo in August of 1978.  But the sense of waiting for this day 
increased after our first use of our big (90-pounds-of-thrust, 0-to-
60 mph in about 2 and a half minutes) engine back in July of this 
year.

Right now, I'm reflecting a little on Galileo's history.  The 1981 
mission.   The 1986 mission and the Challenger disaster.  The 
present mission...getting to Jupiter ten years after we originally 
planned to...

Galileo's mission has been interesting already.  The earlier mission 
would have been at the wrong time to make even a limited 
observation of Shoemaker-Levy.  We might not have discovered a 
moon about an asteroid.  And we're arriving at Jupiter right after the 
discovery of a stellar object in the Pleidies that looks like Jupiter 
(well, it has methane in its atmosphere).

The Jupiter Orbit Insertion (JOI) burn is exciting for two reasons.  
First if it doesn't work, there's no second chance.  Second, if 
something goes really wrong, and we lose the spacecraft, we lose 
the Probe data with it.  That is the worst that can happen, because 
the Probe data is our highest priority. We're not planning to send any 
more probes into gas giants like Jupiter or Saturn (Cassini's probe 
will be into Titan).

In a way, it is strange, because the Orbiter mission seems more 
complex than the Probe mission.  At one point in Galileo's design, the 
two missions were separated into an Orbiter and a Probe 
carrier/relay. Not that the Probe mission is easy.  It isn't.  The 
problems of Probe entry and survival (remember, this will move at 
over 100,000 miles an hour, the fastest man-made object in 
history), and of the relay link are significant.  It's just that the 
Orbiter is an even bigger task.

I wonder what Galileo will discover.  I suspect that the Probe will 
find something surprising.  And what about the Orbiter satellite 
encounters?  Will we be able to tell if Europa is truly ice-crusted 
with an underground ocean?  (No, Europa does not resemble Europe...). 
We originally planned to take enough pictures of Europa to be able to 
answer this question.  Now, without our high gain antenna, it will be 
harder to tell.

Am I nervous about what I just called "final exam" day?  Oh yes.  
Will we hear anything useful from the Probe?  Will the heat shield 
work, will the parachute work?  Will the radio link work...?

Will our 400 Newton engine work?  We are ready for any recoverable 
failure... but what if the filters clog or there is some other 
unexpected underperformance.  Or even a surprise return to earlier 
engine performance expectations?

Also the radiation environment.  The shielding.  Will there be 
disruptions to the spacecraft's operations, events like PORs (Power 
Outage Resets) or SEUs (Single Event Upsets)?  How many can we 
afford? How will they affect us?  What will our telemetry link be 
like?

My guess is that there will be a small engine underperformance 
today at Jupiter Orbit Insertion (JOI).  When we did our first 400 
Newton engine burns in July of 1995, my guess was that there would 
be a  small engine overperformance (I was wrong).  There were 
plenty of experts on the engine to ask about it.  And, back in July, I 
found a way to ask them! I put up a list of all possible burn durations 
(in seconds) and ran a pool, offering a beer to the winner!  The engine 
experts, the accelerometer experts, the managers...all sorts of 
people guessed.  I did too.  But the winner was the System Fault 
Protection Engineer!

I am running the same pool for the length of the JOI burn.  The burn 
should end when we have changed our velocity by the proper amount, 
so the engine performance should be decisive in determining the 
length of the burn.  We'll see who guesses what!  I've upped the 
award this time.  The winner will get two CDs of classical music 
(Holst's "The Planets" and Mozart's "Jupiter Symphony").  As I said, 
this is the best way to tell what the engineers really think.  Most of 
them seem pretty confident about the things they are responsible 
for.

I'm not particularly nervous about events under our control.   If the 
burn is a little off, we're ready to correct it with an Orbit trim 
maneuver either on Saturday morning or on January 2.  This evening, 
I will start coordinating the Orbiter Engineering Team effort to get 
ready for the first of these maneuvers.  We'll have to start by 
figuring out how much the mass of the spacecraft changed at JOI.  
That needs to be done by midnight.   Then from 5 AM to 10 AM Friday, 
we'll implement the navigation team's request for a trim maneuver 
(unless the maneuver is canceled).  For some of us, today will be a 
long day.  If we are going to do a maneuver on Saturday, tomorrow 
will be my longest day.

I've spent several years working on Galileo.  Among other tasks, I 
designed a fault protection scheme and reviewed several others.  I 
helped decide how serious some of the radiation threats to the 
spacecraft would be.  I spent a year checking the computer hardware 
to make sure it was redundant (that is, that its critical functions 
had a backup).   If Galileo is a success, I'm going to feel that this 
work has paid off.

Steve Collins AACS Backroom: . . . . Thu, Dec 7, 5:34PM PST 
7 of my friends and I are in my office in the 8th floor "backroom 
area" watching the same telemetry as the MSA AACS crew. We are 
not officially on shift but are just here to help out if things go sour. 
My official MSA shift starts several hours from now and goes until 
midnight (I guess I miss the party...)

Steve Collins AACS Backroom: . . . . Thu, Dec 7, 5:44PM PST 
I'm an attitude control engineer. I've been on the project for 2 years. 
I have bachelors degrees in physics and theater arts. For hobbies I do 
modern dance, rock climbing and mountain biking. The propulsion 
team just reported that the burn is proceeding according to predict. 
We have now burned longer than we did during ODM. We now have 187 
m/sec out of 644.4 planned. 

Randy G-G: . . . . Thu, Dec 7, 6:24PM PST 
What a rush! The only thing I remember comparable to this was 
during the Shoemaker-Levy/Jupiter interactions, when I was pulling 
Hubble images off the Net as fast as they were being posted, and 
putting them up on our company network, and then going home and 
seeing the images on CNN *hours* later. And there was not the neat 
human interaction of this chat group then. Virtual champagne to the 
Galileo crew!

Brett: . . . . Thu, Dec 7, 7:42PM PST 
So nice communicating with all of you. This was my first time on 
the web. God Bless.

Picard:: . . . . Fri, Dec 8, 11:46AM PST 
Hello! On what frequency does Galileo communicate with the Earth? 

Greg LaBorde, Galileo Systems Engineer: . . . . Fri, Dec 8, 11:48AM PST
Galileo is on S-band microwave. Uplink is about 4GHz, downlink 
around 2.8GHz. 

Greg LaBorde, Galileo Systems Engineer: . . . . Fri, Dec 8, 11:48AM PST
Regarding the "Probe Status Message", the Relay Radio Receivers 
(RRHs) put the received Probe data into "frames" which are then sent 
out and stored on the tape recorder. These "frames" include status 
information about the receivers that is not available as direct 
telemetry measurements. The "status message" was a direct memory 
readout of the RRH's "frame buffer" to snatch one of these frames "in 
situ." This gave not only the indication that both receivers were 
locked onto the Probes transmitters, but also a tiny snippet of the 
Probe's data. However, the Probe's data is heavily encoded, so you 
need a lot of it to be able to decode it. Thus that snippet does not 
really tell us anything. 

Tony Murphy: . . . . Fri, Dec 8, 12:30AM PST
Congratulations to the whole team. What an achievement, it has been 
a long time since Mars and even longer since I sat up very late one 
night with my Dad in 1969 and watched Armstrong step out onto the 
lunar surface. Well done!!

Greg LaBorde, Galileo Systems Engineer: . . . . Fri, Dec 8, 12:32AM PST
It really is a team effort. The people who built it, tested it, analyzed 
it to death, launched it, and have flown it. You even have to go back 
to those who originally conceived of the idea to send an orbiter and a 
probe to Jupiter and would not let it die, despite the setbacks.

PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011

GALILEO MISSION STATUS
December 7, 1995
3:15 p.m.

Radio transmissions indicate Galileo's Jupiter atmospheric
probe mission has succeeded, with confirmation that the probe
signal has been received by the orbiter as the probe began
parachuting into Jupiter's clouds.

"At 3:10 p.m. PST, we received data from the Galileo orbiter
showing the radio link between the probe and Galileo had been
achieved as planned," said Galileo Project Manager Bill O'Neil.
The data we received is a status indicator to show us that the
probe was working and that it was transmitting data to the
mothership."

A sampling of data from the probe mission will start being
played back to Earth Sunday.

Galileo engineers now await the start the of the
spacecraft's critical 49-minute  rocket firing that will start at
5:19 p.m. PST and is scheduled to end at 6:08 p.m. PST  The
engine burn will brake Galileo and allow it to enter orbit around
Jupiter for its two-year mission.