[ Oran/NASAChatHost - 2 - 09:31:44 ]
Hello to our early arriving chat participants. Today's chat with Linda Spilker will begin in approximately 30 minutes. Be sure you have read Linda's profile at http://quest.arc.nasa.gov/women/bios/ls.html to prepare your questions.

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Today's chat will be MODERATED in order to help Linda keep up with our questions. DON'T WORRY if you don't see your questions appear on your screen immediately during moderation. We will post a few questions every few minutes during the chat.

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At the conclusion of the chat, please share your thoughts with us at http://quest.arc.nasa.gov/qchats. We look forward to hearing from you!

[ Oran/NASAChatHost - 5 - 10:00:22 ]
Studying planets like Saturn helps us understand more about Earth. The Cassini spacecraft will spend four years in orbit around Saturn to help us learn more about it. Linda Spilker has worked on the Cassini project since 1988. She is the deputy project scientist for the Cassini mission, and a member of the Cassini Composite Infrared Team. Her responsibilities include helping team members put together the best science possible for the Cassini's four year study of Saturn. But she is also interested in learning more about Saturn's rings and how they work.

[ Oran/NASAChatHost - 6 - 10:01:04 ]
We're glad you could join us for today's chat! And now, here is Linda Spilker to answer your questions.

[ LindaSpilker/JPL - 10 - 10:03:55 ]
RE: [EmilyCHS] Ho much interface do you have with people who work on other missions. For example the Mars mission. Are you fearful you may loose the Cassini craft?
Working at JPL I get a chance to interact with people on many other missions. It was very sad to see that they have been unable to contact the Mars Lander. Cassini is a very sturdy spacecraft. Since it takes us 7 years to reach Saturn we built Cassini with lots of backup systems to make sure we will get there. Cassini has been performing flawlessly so far! I am excited about getting to Saturn.

[ LindaSpilker/JPL - 12 - 10:06:53 ]
RE: [Toni] Hello Linda! Do you have any advice for those of us who are ready to start a second or third career and would like it to be in planetary science or aerospace engineering? I am preparing to go back to university to get a degree to put me on one of these paths. How much can I contribute to the science community/engineering industry in a career spanning only 20 years or so? I assume I need to be very focused on my career goals from the very start. Thank you.
I would definitely encourage you to study planetary science or aerospace engineering. I did not go back to school to get my Ph.D. until my daughters were in school. I am very glad I decided to pursue an advanced degree. It has helped my career as a scientist tremendously. In twenty years you will be able to contribute a great deal. Astrobiology is a growing field right now with the possibility of looking for life on other planets.

[ LindaSpilker/JPL - 13 - 10:09:18 ]
RE: [BurtonValley] We chatted with you last year. You told us that it will fly by Venus again on June 24, 1999 and then fly by the Earth on August 18, 1999. After that, we fly by Jupiter and then on to Saturn! What has happened with the mission and feedback you have gotten since you told us about the launch in 1998?
The flybys of Venus and Earth were both very successful. We acquired science data as well as using both of these planets for gravity assists (giving us an extra "boost" to Saturn). We looked for lightening on Venus but did not see it. We also got pictures of the moon. The pictures and data are on JPL's home page. Now we are busy planning the Jupiter flyby and we are also thinking ahead to the science measurements we plan to make when we get to Saturn.

[ LindaSpilker/JPL - 15 - 10:12:20 ]
RE: [Stacie] What is the Cassini Mission? I read your profile but I am still not clear about it.
Cassini is a mission to study the Saturn system. We will spend four years in orbit around Saturn studying its rings, moons, magnetosphere and Saturn itself. Saturn has a very interesting moon called Titan. Titan has a thick atmosphere and all of the molecules that were present in the early Earth's atmosphere. The European space agency built a probe for Cassini (the probe is called Huygens) and we plan to drop this probe into Titan's atmosphere. By understanding more about Titan we hope to understand more about the early Earth and how life might have started there.

[ LindaSpilker/JPL - 19 - 10:19:00 ]
RE: [Oran/NASAChatHost] Linda, while we're waiting for more questions, have there been any major discoveries we have made about Saturn since expending more effort to study the planet?
Yes, we have made many new discoveries about Saturn, especially in the last 20 years. Two Voyager spacecraft flew by Saturn in 1980 and 1981. They discovered a number of new moons orbiting close to Saturn's rings. Voyager also provided us with our first detailed look at Saturn's rings. We saw some unusual rings, such as the F ring, which had kinks and braids in them. Voyager also gave us our first detailed look at Saturn's icy moons. One moon, Enceladus, sits in the middle of the E ring and is somehow the source of the E ring. Cassini will study Enceladus in detail. We also obtained measurements of the composition of Titan's atmosphere as a function of latitude. We found some new molecules at the poles. Voyager also photographed lightning on the back side of Saturn and saw the dark sides of Saturn and the rings for the first time. Many discoveries remain for Cassini!

[ LindaSpilker/JPL - 21 - 10:22:12 ]
RE: [Annika] I'm very interested in astronomy and stargazing, but not really in physics as much. What kinds of jobs do you know of that would not require a lot of complicated physics?
In astronomy there are many jobs that require using the computer to develop models of what we see. There are also jobs for people who want to work at the telescopes and help run them. If you want to use the telescope yourself to figure out something about the universe then you will need to know a little bit of physics. The nice thing about physics is that it will pull together lots of the math you have already learned and put it to use in studying the stars and galaxies.

[ LindaSpilker/JPL - 23 - 10:26:14 ]
RE: [EricaCHS] What is the difference in time travel from Earth to Mars and from Earth to Saturn?
When we send spacecraft to Mars we wait until the Earth and Mars are close together. Then we can get to Mars in less than one year. To go to the outer planets, like Saturn, it takes much longer, especially if you want to go into orbit around them. Voyager 2 launched in 1977, flew by Jupiter in 1979, Saturn in 1980, Uranus in 1986 and Neptune in 1989. Voyager was able to make such a fast trip because ALL FOUR of the planets were lined up just right! This only happens every couple hundred years. At Jupiter Voyager got a big boost of energy to send it on to Saturn. Voyager got enough energy at Jupiter to allow it to leave the solar system. Cassini is a very big spacecraft so we had to use 2 flybys of Venus and 1 of Earth to get enough energy to get out to Saturn. A distant flyby of Jupiter will give us some energy too. Cassini launched in 1997 and will get to Saturn in 2004.

[ LindaSpilker/JPL - 27 - 10:30:07 ]
RE: [SarahCHS] How do international mission differ from missions that are just US missions and why are some international and others not?
International missions have participation from other countries outside the U.S. These countries provide money, scientists and hardware to the mission. In the case of Cassini, the European Space Agency (ESA) provided the Huygens probe (to enter Titan's atmosphere), the high gain antenna (for communication with Earth) and some of the science instruments including the cosmic dust analyzer and part of the magnetometer. Many European scientists are participating also. The advantage of an international mission is that the cost is spread across many countries, making the mission easier to do. It also involves scientists from around the world. NASA and ESA work together to decide which missions should be international. Each agency does some missions themselves as well.

[ Oran/NASAChatHost - 28 - 10:31:07 ]
As a reminder, please share your thoughts about today's chat with us at http://quest.arc.nasa.gov/qchats.

[ LindaSpilker/JPL - 29 - 10:33:56 ]
RE: [BurtonValley] What do you think will be the next planets NASA will explore and why?
NASA will continue to explore Mars, sending missions about every 2 years (when Mars and Earth are close together). NASA is also planning to send a mission to Europa, one of Jupiter's moons. Europa may have an ocean of water under its icy surface and maybe even life! Pluto is also a planet on NASA's list. A spacecraft to fly by Pluto may launch in 2004. We want to study Pluto and its atmosphere to understand something about this planet so far from the sun. A Discovery mission to Mercury was approved recently. We don't know much about Mercury and would like to get detailed pictures of the whole planet. Downstream we may send another mission to Neptune. Comet and asteroid missions are under way or under study as well.

[ LindaSpilker/JPL - 31 - 10:36:03 ]
RE: [CarondeletHS] Hi Linda- You mentioned in your profile that you needed your PhD in order to conduct your own research? Can you explain why this is so important and what you might be doing if you hadn'9t received it?
With a Ph.D. I can write proposals and get funding to do research the way I would like to do it. Without a Ph.D. I would probably have to work with someone else on their science instead. On Cassini I represent all of the scientists on the mission. A Ph.D. (and all the work it took to get it!) gives me credibility with the science community and boosts their confidence in my ability to understand their science and represent it to the project.

[ LindaSpilker/JPL - 32 - 10:38:35 ]
RE: [Stacie] The lightning that was seen on the back side of saturn, does that suggest a weather pattern similiar to our own?
Lightning does indeed suggest weather patterns not unlike our own-- clouds, storms and lightning. The biggest difference is that Saturn's atmosphere is almost all hydrogen with a tiny bit of helium, ammonia and methane. Saturn also has giant storms similar to our hurricanes on Earth. Studying how these storms form and die provides us with information to use to compare these storms to the ones on Earth.

[ LindaSpilker/JPL - 34 - 10:42:20 ]
RE: [Annika] Where around Saturn will Cassini orbit so that it won't be damaged from the rings?
When Cassini first approaches Saturn we will fly very close to the planet, in fact closer than the main rings. What we do is fly above the rings. We fly close to Saturn because that is the best place to burn our engines to slow down and go into orbit around Saturn. We are deep in Saturn's gravity well and there it takes the least fuel to slow down. After that, we will orbit Saturn well outside the main rings. If we tried to fly through them instead, one of the ring particles might make a hole in our fuel tank or damage one of the science instruments. We will fly through the E ring a lot since it extends over so much of the Saturn system. This ring is very diffuse and contains tiny particles that won't hurt us. Cassini is covered with special blankets to absorb hits from small particles without hurting the spacecraft.

[ LindaSpilker/JPL - 38 - 10:47:12 ]
RE: [Oran/NASAChatHost] Linda, you mentioned Saturn has giant storms that occur. Are these storms comparable to "The Big Red Spot" on Jupiter?
Yes, the storms on Saturn are comparable to the giant storm on Jupiter called the Great Red Spot. Saturn does not have anything like the Great Red Spot. Most of its storms look like the white oval storms seen on Jupiter. Sometimes one storm overtakes another one and the two merge, forming one giant storm.

[ LindaSpilker/JPL - 39 - 10:49:36 ]
RE: [Carol] Are your daughters interested in space like you?
My daughters are interested in space but not as interested as I am! They were here at JPL for the Voyager flybys (I worked on Voyager for 13 years) and we took them out of school for a week to go with us to the Cape to watch the Cassini launch. My oldest daughter likes math and biology. They are all good at math and like science. They have heard me say over and over that women are good at math and science too!

[ LindaSpilker/JPL - 43 - 10:53:09 ]
RE: [Carol] What is the ration of men and women who work on the Cassini mission?
There are more men on Cassini than women right now, but over the years I been at JPL more and more women are becoming scientists and engineers. I would guess that it is about 35% women and 65% men overall on Cassini. Women are also rising to positions of higher responsibility at JPL. Some are now Project Managers or Project Scientists.

[ LindaSpilker/JPL - 44 - 10:54:37 ]
RE: [Carondelet] Do most of the people who work at NASA have PH.d's?
No, most people at NASA do not have Ph.D's. Most scientists probably do but they only make up 10% or less of the people at JPL. Most people here are engineers, computer technicians and managers.

[ LindaSpilker/JPL - 46 - 10:56:42 ]
RE: [Annika] I've read that the tiny moons around Saturn may help the rings survive. Do you know if this is true? If so, how?
Yes, the tiny moons help the rings survive by keeping them from spreading out and disappearing. The tiny moons "shepherd" the rings and keep them from spreading. One narrow ring at Saturn, the F ring, has a shepherd moon on each side to keep it together. The tiny moons also create wakes and waves in Saturn's rings.

[ LindaSpilker/JPL - 47 - 10:58:28 ]
RE: [BurtonValley] What are your thoughts on when humans will go to Mars or when and if they will be on missions to other planets?
People will probably not go to Mars for another 30 or 40 years. Many technical challenges, such as surviving such a long trip, living on Mars and returning safely all have to be solved. It would be much easier to set up a base on the Moon since it is much closer. Most of the other planets are probably too hostile to visit any time soon.

[ LindaSpilker/JPL - 48 - 11:00:20 ]
RE: [Theresa] What, specifically, is the Huygens probe supposed to test for?
The Huygens probe will analyze the composition of the atmosphere at various heights as the probe descends. There are also other instruments to measure the temperature and pressure of the atmosphere as the probe falls, to detect lightning, if it is there and a camera to take pictures of the clouds and the surface as the probe gets close.

[ Oran/NASAChatHost - 50 - 11:03:09 ]
For those of you leaving us, be sure to send your comments about today's chat to us at http://quest.arc.nasa.gov/qchats.

[ Oran/NASAChatHost - 51 - 11:04:21 ]
We will now be ending out chat with Linda Spilker from NASA Jet Propulsion Laboratory. We would like to thank everyone for joining us today, and Linda Spilker for sharing her time and career expertise with us. Thank you Linda!

[ LindaSpilker/JPL - 52 - 11:05:11 ]
RE: [Oran/NASAChatHost] We will now be ending out chat with Linda Spilker from NASA Jet Propulsion Laboratory. We would like to thank everyone for joining us today, and Linda Spilker for sharing her time and career expertise with us. Thank you Linda!
You are very welcome! Bye!

[ Oran/NASAChatHost - 53 - 11:05:25 ]
Please join us for our ongoing Women of NASA forums this week with Alda Simpson and Emily Holton. Check the Women of NASA events schedule at http://quest.arc.nasa.gov/women/won-chat.html for more information.