Jan/Holmen Middle School: . . . . Tue, Aug 5, 7:37AM PDT (-0700 GMT)
Testing from Holmen Middle School

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 9:53AM PDT (-0700 GMT)
Jan: Looks good from this end! All the best!

Heribert J. Feige, Dilthey-Schule, Wiesbaden, Germany: . . . . Tue, Aug 5, 9:07AM PDT (-0700 GMT)
When does the chat start, in one or in two hours?

Heribert J. Feige, Dilthey-Schule, Wiesbaden, Germany: . . . . Tue, Aug 5, 9:08AM PDT (-0700 GMT)
OH, I see, it must be in two hours, See you later.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 9:56AM PDT (-0700 GMT)
Heribert: It looks like you logged in a 9 PDT. The chat starts in 3 hrs, which will be noon Pacific Daylight Time. Look forward to chatting with then. (It's now 10 a.m. here in California, so only two more hours to go.)

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 11:48AM PDT (-0700 GMT)
Today's chat with David Mittman will begin in about 10 minutes... Read David's great bio and journals if you haven't already: button

Stephanie/Edmonton: . . . . Tue, Aug 5, 11:42AM PDT (-0700 GMT)
Greetings from the capital city of Alberta! It's expected to get up to 32C or 90F here. Look forward to chatting with you Sandy and Mr. Mittman.

David/JPL: . . . . Tue, Aug 5, 11:45AM PDT (-0700 GMT)
Test Message

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 11:47AM PDT (-0700 GMT)
Hi Stephanie! Looks like a hot & toasty one in Edmonton today! It's already 90F here at the Ames Research Center, about 40 miles south of San Francisco.

David/JPL: . . . . Tue, Aug 5, 11:48AM PDT (-0700 GMT)
Greetings to you, Stephanie. I'm just getting my "sea legs" here. It's not easy switching gears from Mars planning to terrestrial chatting!

David/JPL Mars Pathfinder: . . . . Tue, Aug 5, 11:49AM PDT (-0700 GMT)
Since we're playing the temperature game...it'll be over 100F in Pasadena today!

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 11:53AM PDT (-0700 GMT)
Between Edmonton, San Francisco and Pasadena, it sounds like we have a western heat wave going on!

Stephanie/Edmonton: . . . . Tue, Aug 5, 11:59AM PDT (-0700 GMT)
Sandy, Too hot for me! How do you change the handle so it is clickable? I want to put up my email address.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:01PM PDT (-0700 GMT)
Stephanie: you can't make your handle clickable, but you can put your email address as your handle if you'd like. I agree with you about the heat! Let's go swimming!!!

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:06PM PDT (-0700 GMT)
Welcome to yet another Live From Mars WebChat! Our guest today is David Mittman from the Jet Propulsion Laboratory in Pasadena, CA. As the flight engineer on Mars Pathfinder, David is responsible for the day-to-day operations of the lander and rover, specifically in planning the spacecraft's activities and sending commands to the spacecraft.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:06PM PDT (-0700 GMT)
Welcome David!

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:07PM PDT (-0700 GMT)
Good day, everyone. I'm David Mittman, a mission planner with the Mars Pathfinder project. I'm currently sitting in my office a few feet from the control room featured in the NASA TV coverage of the landing.

Stephanie/Edmonton: . . . . Tue, Aug 5, 11:54AM PDT (-0700 GMT)
Mr. Mittman, are the lander's batteries all charged up now?

David/Mars Pathfinder: . . . . Tue, Aug 5, 11:58AM PDT (-0700 GMT)
Stephanie, we're awaiting the start of the data downlink for Sol 32. Information received from Sol 31 indicated that we were successful in reconditioning the lander battery. What we don't yet know is how much of an improvement we've been able to achieve.

Terry, Webster in Stockton Ca: . . . . Tue, Aug 5, 12:04PM PDT (-0700 GMT)
Hello, we just got logged in.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:05PM PDT (-0700 GMT)
Hi Terry in Stockton! Welcome!

Jan W/Holmen School District: . . . . Tue, Aug 5, 12:05PM PDT (-0700 GMT)
Hi, this is Jan's class from Holmen joining the chat!

Jan F/ Holmen School District: . . . . Tue, Aug 5, 12:05PM PDT (-0700 GMT)
Hi ! This is my very first time talking to NASA.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:06PM PDT (-0700 GMT)
Hello Jan F. Very glad to have you join us today for your first chat! I think you'll have a pretty good time :-)

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:06PM PDT (-0700 GMT)
Glad to have you here, Jan F. I must say that this is my first time talking to Holmen School District!

Jan F/ Holmen School District: . . . . Tue, Aug 5, 12:07PM PDT (-0700 GMT)
What do you think is the greatest achievemnet of the Pathfinder so far? Any disappointments?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:08PM PDT (-0700 GMT)
Jan: I think the absolute best acheivement is the actual landing on Mars on July 4. Everything since then has been the icing on a very "sweet" cake.

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:10PM PDT (-0700 GMT)
The most disappointing events are those days where mistakes make us lose a day's activities on Mars. Good question, Jan F!

Sue, Sonora: . . . . Tue, Aug 5, 12:08PM PDT (-0700 GMT)
Hi, Sandy and David, I am looking forward to hearing the latest info on Sojourner!

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:08PM PDT (-0700 GMT)
Hello Sue. Glad you could join us! Send in your questions!

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:10PM PDT (-0700 GMT)
Welcome, Sue. What kind of information on Sojourner are you looking for?

: . . . . Tue, Aug 5, 12:08PM PDT (-0700 GMT)
Heribert J. Feige from Germany. I am the first time here and I find it great!

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:09PM PDT (-0700 GMT)
Welcome Heribert from Germany! Very glad you are here today! Where are you in Germany and what time is it?

: . . . . Tue, Aug 5, 12:11PM PDT (-0700 GMT)
Good evening Mr. Mittman. It is now 21.10 in Germany and it was a hot day in Germany also. Shannon/7th grade: . . . . Tue, Aug 5, 12:10PM PDT (-0700 GMT)
In your bio you said the batteries on PF aren't like the Energizer bunny--so what's your prediction on how they'll last? Is there anything you can do to lengthen their lifetime?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:12PM PDT (-0700 GMT)
Shannon: We've just gone through an exercise to try and increase the amount of energy that our rechargeable battery can hold on the lander. We've also stopped using it as much at night. By not using the battery so much at night, we'll be able to extend the amount of weather data we'll be able to collect.

Sue,: . . . . Tue, Aug 5, 12:11PM PDT (-0700 GMT)
Could you explain the color of the Mars atmosphere (sky)?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:14PM PDT (-0700 GMT)
Sue, if you've ever been in Los Angeles in the summer, you'd know that the most beautiful colored sunsets are on the smoggiest days. The smog particles catch the sun and give color to the sky. The same thing happens on Mars, except that the instead of smog, there are fine grains of dust.

Terry, Webster in Stockton Ca: . . . . Tue, Aug 5, 12:12PM PDT (-0700 GMT)
What activities on the west coast (california central valley) are avable to get students involved in mars pathfinder in spetember

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:16PM PDT (-0700 GMT)
Well, Terry, I don't have a specific list of events, but if you are interested in having someone from JPL come and speak to your civic organization, you can contact the public information office here at JPL. Catherine L Davis, MED Education and Public Outreach Office, 818-354-6111.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:15PM PDT (-0700 GMT)
Terry: You can also check out the "Live From Mars" web site for all the K-12 activities that our project will be sponsoring. Go to: button

Sue,: . . . . Tue, Aug 5, 12:12PM PDT (-0700 GMT)
Also, how did they manage to get pictures of the earth from Mars?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:17PM PDT (-0700 GMT)
Sue, I know of one picture that was supposed to show Earth from Mars, but clouds covered the sky at that time. Earth would appear as a bright blue star in the Martian sky. I believe that more attempts will be made to take a picture of Earth from Mars.

Stephanie/Edmonton: . . . . Tue, Aug 5, 12:13PM PDT (-0700 GMT)
Where will the rover go after mermaid dune?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:18PM PDT (-0700 GMT)
After Mermaid Dune, Stephanie, Sojourner will travel through the Rock Garden to the Bookshelf area.

Sue,: . . . . Tue, Aug 5, 12:15PM PDT (-0700 GMT)
Thank you for that information about the dust smog. I thought it might have had something to do with the CO2 and light refraction. I am glad it is much simpler than that.

Shannon/7th grade: . . . . Tue, Aug 5, 12:17PM PDT (-0700 GMT)
What percentage of your day is spent being a mission planner vs a flight controller?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:20PM PDT (-0700 GMT)
Actually, Shannon, I'm not a flight controller any more! My last shift as flight controller was the night before Landing. I helped guide the spacecraft toward its landing site and got a chance to attend the meeting where we decided not to change our flight path. I got off shift at midnight and went home for some sleep. After that, I only had Mission Planning duties.

Sue,: . . . . Tue, Aug 5, 12:20PM PDT (-0700 GMT)
What new information have the geologists learned about the Mars suface from the rocks, mermaid dune, etc.? Have they learned anything from the tests where they had sojourner dig into the surface?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:23PM PDT (-0700 GMT)
Sue: A few of the scientific findings are posted at the Mars Pathfinder web site. I'll let the scientists presentations speak for themselves. A few items of interest include the observation that a whitish material seems to underlay the sand surrounding the landing site. The rover's wheels actually scratched away enough of the soil to reveal the white material underneath. In other areas, the white material is at the surface. The area known as Scooby Doo is one of these white areas.

Bill/Gaithersbury, MD: . . . . Tue, Aug 5, 12:20PM PDT (-0700 GMT)
I don't understand why you are giving all the objects on Mars comical names. Can you explain this to me? Everything with Viking was so "scientific" and serious!

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:26PM PDT (-0700 GMT)
Well, Bill. Even the Viking scientists named their rocks! Remember Big Joe? There are so many rocks that using numbering schemes in everyday conversation would be difficult. Perhaps a more scientific method of identification will be used to classify the rocks after the project is over. The scientists will probably adopt whatever scheme is appropriate at that time. For now, day-to-day operations are made alot easier by being able to refer to the rocks by "name."

Aaron/Chicago: . . . . Tue, Aug 5, 12:22PM PDT (-0700 GMT)
Guiding Pathfinder to Mars--wasn't that like the ultimate in jobs??? What will you do when Pathfinder is finished? Are you going to work on the upcoming Mars Global Surveyor or any of missions in the 2000s?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:28PM PDT (-0700 GMT)
The workload on Mars Pathfinder is tapering off, Aaron, so I'll be devoting my time to two different projects besides Mars Pathfinder. The Space Infrared Telescope Facility is a Hubble-like telescope to observe infrared objects in our universe. I'll be designing the mission planning software for that mission. I'll also be working on a project called X2000 which will attempt to put some of our currently ground-based mission planning "smarts" on-board a spacecraft.

Stephanie/Edmonton: . . . . Tue, Aug 5, 12:23PM PDT (-0700 GMT)
David, has your hours at work become more normal lately?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:29PM PDT (-0700 GMT)
That's a very timely question, Stephanie. Today is the first day since July 3 that I've been able to come in at a normal hour and leave at a normal hour. We're trying to "unlink" our work hours from the Martian day.

Feige/Dilthey-Germany: . . . . Tue, Aug 5, 12:23PM PDT (-0700 GMT)
What kind of programming language do you use for controlling the rover?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:30PM PDT (-0700 GMT)
Feige, most of the software which is used to control the rover from the ground was written in the 'C' programming language. The mission planning software that I wrote for laying out the lander's activities is written in LISP. What can I say, I'm a rebel!

Sue,: . . . . Tue, Aug 5, 12:27PM PDT (-0700 GMT)
David, what is most significant to you about 1. being involved with this project and 2. the project overall?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:32PM PDT (-0700 GMT)
Well, Sue. My first "flight project" was Mars Observer, where I played a peripheral role supporting some planning software. I was there when Mars Observer was lost. Being involved in Mars Pathfinder from the beginning has been the most exciting part of the project. Watching the design progress, the hardware being built. It was a once-in-a-lifetime opportunity that I'm trying very hard to duplicate!

Stephanie/Edmonton: . . . . Tue, Aug 5, 12:29PM PDT (-0700 GMT)
David, is the shiny thing in one of pathfinder's images the backshell (mentioned in the press release)?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:33PM PDT (-0700 GMT)
I don't think there is a definitive answer for your question about the backshell, Stephanie. We may be able to get better images soon, but it seems likely that it is the backshell.

Terry, Webster in Stockton Ca: . . . . Tue, Aug 5, 12:30PM PDT (-0700 GMT)
When you send commands to the pathfinder, what programing languages do you use?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:35PM PDT (-0700 GMT)
Terry: I'll have to make a distinction between the "language" of the commands and the language used to develop the programs which help us assemble the commands. The lander understands its own custom set of commands, the Mars Pathfinder Lander Command Dictionary. On the ground, we have a whole suite of software programs which help us write command sequences. Those helper programs are mostly written in 'C' (and LISP!).

Angie/Cucamonga, CA: . . . . Tue, Aug 5, 12:31PM PDT (-0700 GMT)
I read in your bio that you have a BA in psychology. How did thgat degree help you get your job on the Mars team?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:36PM PDT (-0700 GMT)
Angie, the Psychology degree stemmed out of my interest in Artificial Intelligence and Cognitive Science. I don't actually use any psychology on my coworkers...

Shannon/7th grade: . . . . Tue, Aug 5, 12:34PM PDT (-0700 GMT)
What is this backshell that you're talking about? It was something discovered on Mars???

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:39PM PDT (-0700 GMT)
Shannon, the backshell is a part of the entry vehicle which encapsulated the Mars Pathfinder lander on its way down through the Martian atmosphere. The backshell contained the solid rockets which slowed our descent before hitting the surface. Shortly before contact, the backshell was cut away and flew off into the distance, carrying our parachute with it. We may have discovered where the backshell went in recent images received from Mars. In the distance is a small shiny object of about the right size. Discovering the backshell location is not of critical importance, but it will provide our Entry, Descent, and landing engineers with another piece of information on how the EDL system performed.

Debbie/mom of homeschool: . . . . Tue, Aug 5, 12:38PM PDT (-0700 GMT)
David: what do you tell your children about what daddy does at work all day? How do you explain to them about landing a craft and a walking "tonka" toy on Mars? I'm trying to figure out how to explain these kinds of things to my kids!

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:42PM PDT (-0700 GMT)
Debbie, my son (4 1/2) always asks if I'm going to eat lunch at my spacecraft. He identifies with the craft more than with any boring office! As flight controller, I was able to show them Australia and Spain on a globe, and let them listen in on my communications with those Deep Space Network stations. I think what has really helped in their understanding is the constant repetition of Mars Pathfinder information in our home. I don't suggest that particular avenue...

Seriously, all the pictures and manipulatives you can get your hands on are great. Comparing and contrasting Mars and Earth is also helpful. Interestingly enough, my daugher (6 1/2) has about the same level of understanding about Mars and Mars Pathfinder. I think more advanced understanding should come at about age 7 1/2 or 8.

Carrie/Glencliff HS: . . . . Tue, Aug 5, 12:40PM PDT (-0700 GMT)
David- I teach Astronomy & physics. I have taken students to the Huntsville Air & Space Museum for 8 years now. Many students are interested in space & computer technologies. I noticed you have a non-traditional backgroud for your position. What do you think is the best single advice I could give to HS students? Mrs. t

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:47PM PDT (-0700 GMT)
Well, Carrie, I'd say that a love of learning is the best skill any person could have. My start with Mars Pathfinder was through computer programming, but I've taken only one or two formal classes in computer science. Certainly many years of tinkering (okay, hacking) didn't hurt.

Sue,: . . . . Tue, Aug 5, 12:41PM PDT (-0700 GMT)
Thanks & Bye.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:42PM PDT (-0700 GMT)
Bye Sue. Thanks for joining us today! Be sure to sign up next week's chat.

Heribert/Dilthey-Germany: . . . . Tue, Aug 5, 12:42PM PDT (-0700 GMT)
My daughter want to get a job like you, what would you propose to study?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:50PM PDT (-0700 GMT)
Well, Heribert, that' a hard question! Certainly a love of computers is very important. But, not all of our folks are computer programmers. Love of science and an interest in technology are important, but many of us don't have science backgrounds. Your daughter will have to study the thing that she most loves and use that knowledge, along with her native intelligence and ability to learn and adapt, to find a spot in a team like Mars Pathfinder.

Stephanie/Edmonton: . . . . Tue, Aug 5, 12:44PM PDT (-0700 GMT)
David, do the scientists ask you to tell the rover to do traverses that are quite risky?

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:52PM PDT (-0700 GMT)
Well, Stephanie, the Rover is doing things which are a bit more risky now that we're out on Sol 33...

At the start of the mission it was made clear to the scientists that the Rover drivers were the final word on what the Rover would be doing and that the mission planners were the final word on what the lander would be doing. As we've learned more about how to operate the lander/rover we've been more comfortable doing "riskier" things.

Steven/Seattle: . . . . Tue, Aug 5, 12:47PM PDT (-0700 GMT)
Now that you're working more typical hours again, describe your typical day...

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:55PM PDT (-0700 GMT)
Well, Steve, a typical day *always* starts with a cup of coffee. I've not had a typical day yet, so I'll describe today. I got home this morning at 2 AM after planning Sol 33. I got to sleep until about 7:30 AM when I got up to help prepare my son for summer school. I actually didn't get into work until about 10:00. I've already done some SIRTF work. After this Web chat, I'll be starting to plan Sol 34. Most likely I'll go home about 5:00 PM and be back at work again at about 8:00PM to finish up the planning. I'll make it home again by about 11:00 PM. Next week we should be finished transitioning to a schedule which has the mission planners coming to work during daytime shifts only. We're not quite there yet.

Stephanie/Edmonton: . . . . Tue, Aug 5, 12:54PM PDT (-0700 GMT)
Thanks for answering my questions, David! See you in next week's chat, Sandy! Bye!

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:57PM PDT (-0700 GMT)
Goodbye Stephanie! Chat with you next week!

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:58PM PDT (-0700 GMT)
EVERYONE: Thank you very much to all of you for participating in today's WebChat with David Mittman. You had some great questions for him! And a very special thanks to David for taking the time to chat with us today. We hope to chat with you again in the future!

David/Mars Pathfinder: . . . . Tue, Aug 5, 12:58PM PDT (-0700 GMT)
Thanks for all the good questions, everyone. I hope I had a chance to answer them all. Our next Mars Pathfinder news conference should be later this week. That's all from Mars...

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 12:58PM PDT (-0700 GMT)
To sign up for next week's chat go to: button

Heribert/Dilthey-Germany: . . . . Tue, Aug 5, 12:59PM PDT (-0700 GMT)
Thank you very much, David, for answering my questions and best greetings to Sandy.

Sandy/NASA Chat Host: . . . . Tue, Aug 5, 1:01PM PDT (-0700 GMT)
Heribert: You're most welcome :-) Please join us again!