[ Oran/NASAChatHost - 1 - 08:17:11 ] Thank you for joining us for our forum with Nancy Roman from NASA Goddard Space Flight Center. Your questions will be posted and answered by Nancy at various times during our forum. Be sure to check back to read her answers to your questions.

[ Oran/NASAChatHost - 2 - 08:18:52 ]
At the conclusion of the forum, be sure to send your comments to us about this forum at http://quest.arc.nasa.gov/qchats. Thank you again for joining us. We look forward to hearing from you, and hope you enjoy the forum!

[ NRoman/GSFC - 11 - 12:40:53 ]
I checked the list that NASA posts of operating missions including foreign missions in which NASA is involved. This list contains 9 US satellites plus one that failed in its primary mission but is being used for other astronomical observations, 10 planetary probes (including probes to comets and asteroids), 3 foreign satellites, and one foreign probe. Some of the probes have not yet reached their targets. There are three missions I do not recognize and whose Web pages I am unable to access at the moment. There are also other foreign satellites and probes without US involvement.

[ NRoman/GSFC - 12 - 16:26:56 ]
RE: [SpaceCampTrainees] U.S. SPACE CAMP 4th-6th grade trainees are here. We are excited about the opportunity to chat with Nancy Roman. You started an astronomy club when you were only 11. Was there a single person or an event that sparked your interest in astronomy?
I do not know what sparked my interest in astronomy. I remember my mother showing me the constellations and the northern lights (I lived in northern Michigan for a while as a child) but she also showed me trees and flowers and birds, read poetry, taught me to enjoy music and even how to cook. It is not clear why astronomy stuck. I do remember being impressed by a bright meteor (shooting star). At that time I lived on the edge of the city of Reno so the sky was clear and, at night, dark. This meteor appeared at dusk, before the sky was completely dark and crossed nearly from horizon to horizon. However, I believe I was interested in astronomy even before then. Of course very many children find astronomy fascinating when they are about 10 - 12. I just never out-grew it.

[ NRoman/GSFC - 13 - 16:27:27 ]
RE: [SpaceCampTrainees] Will the gas giant planets ever become solid?
It is highly unlikely that the gas planets will ever become completely solid. Of course, regions of their interiors are solid now. Their gravity is large enough that they will be able to hold on to their thick atmospheres for the life of the solar system, or at least the life time of the sun.

[ NRoman/GSFC - 14 - 16:27:45 ]
RE: [SpaceCampTrainees] You have done a lot of work on astronomical satellites like Hubble and Chandra telescopes. How many astronomical satellites are out there?
I have not kept track of all of the current astronomical satellites. There are quite a few. In addition to the ones that have been launched by NASA, Japan has several active astronomical satellites as do the European countries. In the US, DoD has also launched satellites that carry astronomical equipment, particularly for studying the sun. I'll try to find a better answer later.

[ NRoman/GSFC - 15 - 16:28:04 ]
RE: [SpaceCampTrainees] I have been reading about light pollution, which makes it hard to see stars from my yard. How can I reduce light pollution in my community?
The best thing you can do to reduce light pollution in your community is to let the adults know that you care. Also tell them that wasting light to light the sky and keep you (and them) from seeing the sky wastes energy and money. More efficient lighting that lights the areas needing light but not the sky gives better results for the money. There is an organization, started by an astronomer from the Kitt Peak Observatory in Arizona that is attempting to spread this message world-wide. Although its membership contains many astronomers and amateur astronomers, it also includes lighting engineers and even politicians interested in better lighting in their communities. It is called: International Dark-Sky Association, Inc. (IDA) 3225 North First Avenue] Tucson, AZ 85719-2103 You may want to investigate its Web site at: http://www.darksky.org Also, you may want to refer your parents to the site. They give a substantial amount of advise on outdoor lighting problems.

[ SpaceCampTrainees - 30 - 21:14:10 ]
We have learned a lot. Thank you for your time! We'll come back if we think of more questions to ask.

[ NRoman/GSFC - 32 - 08:48:01 ]
RE: [Heather] I have been thinking about pursuing a graduate degree in astronomy; however, I did not take any math or physics classes in college. The last math I had was Calculus in high school. I was wondering if there was any advice you may be able to give me. Would I get another bachelor's degree? Or would it be possible for me to enroll in graduate courses now?
Heather, I think that you would find graduate school in astronomy very difficult without having had math and physics in college. You should not need to take another bachelor's degree but you would need to take enough courses that you would probably spend at least two years catching up. I suggest that you get hold of some college text books, starting with freshman books. (You can ask a local college for suggestions.) Try studying these on your own. If you think you understand them and can learn the material, try some sophomore books. Then ask the college where you plan to study if you can get advanced credit for the material you have learned on your own. You will probably have to take a test. I do not recommend going beyond the sophomore level on your own. Of course, you would not be the first person to go back to college to take a degree in a new field and you may find simply going back to college for the more elementary course easier and more satisfactory.

[ NRoman/GSFC - 33 - 08:48:41 ]
RE: [Tony] Do you believe that X-ray telescopes should be granted more money by to further advance their technology?
The technology of X-ray telescopes is developing quite rapidly. While more money is always welcome, I do not think that the cost of technological development is the main problem. The primary problem is that X-ray telescopes must be in space and must point at least fairly accurately and stably. This is expensive. However, even with Chandra just launched, there are several other X-ray telescopes being developed.

[ NRoman/GSFC - 34 - 08:49:26 ]
RE: [Stephanie] How do you see the Milky Way from an outside perspective when you're in it?
You really cannot see the Milky Way from the outside since, as you note, we are in it. However, we can get a pretty good idea of how it would look by looking at other galaxies and comparing them with what we can learn about our own galaxy. We can map the locations of stars of various kinds within a couple of thousand light years from the sun and can map the neutral hydrogen that, in other galaxies, outlines the spiral arms, throughout the Milky Way. We can also study the motions of stars and thus learn where they will be at various times in the future. Putting this information together, we get a pretty good picture of our galaxy. We think it looks very much like the Andromeda Galaxy (M31) that is the nearest large galaxy to our own although ours is slightly smaller.

[ NRoman/GSFC - 46 - 08:52:33 ]
RE: [SpaceCampTrainees] Is there a black hole at the center of the Milky Way?
Yes, we think that there is a black hole at the center of our galaxy. We have been able to observe motions very close to the center of the galaxy. These indicate that there is a mass equivalent to a million suns within a sphere with a radius about equal to the distance of the sun from the nearest other star. Only a black hole could have that density. It is probable that all spiral galaxies have black holes in their centers although they vary in size. The one in the Milky Way is pretty small. The largest are those in quasars.

[ NRoman/GSFC - 47 - 08:54:38 ]
RE: [SpaceCampTrainees] Is Pluto a planet? What is the difference between a planet and an asteroid or a moon?
As you may have heard, there has been a great deal of controversy in the past year about whether Pluto is a planet or an asteroid. The problem is that there is no clear definition to distinguish between them. In the past, everything that we called a asteroid spent most of its life between Mars and Jupiter, in a region in which astronomers used to think that there should be a planet. Thus an asteroid was simply a small body (smaller than the earth's moon) in that part of the solar system. That would make Pluto a planet since it is in a very different location. However, Pluto is much smaller than any other planet and its orbit is less circular. Since the orbit of Pluto crosses that of Neptune, it has been suggested that Pluto was once a moon of Neptune and was knocked away in a collision with another large body. This would make it more similar to an asteroid than to the other planets but neither its nature nor its origen are really clear. The astronomical community has decided to continue to call it a planet but you can decide for yourself.

[ NRoman/GSFC - 48 - 08:56:20 ]
RE: [SpaceCampTrainees] Is there a Planet X beyond Pluto?
Some people think that they have detected the gravitational pull of a planet beyond Pluto but the evidence is very weak and most astronomers do not accept it. There are many comets beyond Pluto but these are too small to be consedered a planet.

[ NRoman/GSFC - 52 - 10:47:13 ]
RE: [TonyAFJROTC] Do you believe that placing more telescopes into orbit like Hubble is a risk not worth taking, or should we concentrate on developing Earth based obsevatories?
Ground-based and space-based telescopes are complementary. Telescopes in space can observe wavelenghts (colors) that cannot be seen through the earth's atmosphere. Perhaps you have seen the striking images that have recently been received from the new X-ray telescope, Chandra. Fortunately for humans and other forms of life, our atmosphere keeps X-rays from space from reaching the ground so we must go into space to get pictures such as these. Even in the wavelengths that do reach the earth, there are types of images that ground-based telescopes cannot get with resolution comparable to those from telescopes like the Hubble. On the other hand, ground-based telescopes are normally larger and hence can collect more light than those in space. They can be repaired more easily and the various auxilary instruments that take different kinds of observations can be interchanged and upgraded more frequently.

[ NRoman/GSFC - 53 - 10:48:16 ]
RE: [Amanda] Hi Ms. Roman - In regards to your long history in astronomy, we are wondering what types of changes you have seen over the years with relation to astronomy and new technologies for viewing and capturing images.
There have been several major changes in astronomy since I started to work in the field. When I started, there was very little interest in the planets. It was felt that not much more could be learned about them. To a large extent, this was true. The great increase in our knowledge of the planets has come from the space probes that observed them from nearby. The planetary data collected from the ground in recent years, that is not insignificant, resulted from new instrumental techniques. There was also relatively little interest in galaxies and cosmology was considered a philosophical subject, not a scientific subject. Almost the entire astronomical community was working on stars - and largely middle age stars like the sun. We were interested in variable stars and why they varied but our knowledge about these was comparatively limited. Today, we are very interested in planets, not only in our own solar system but, in the past two years, around other stars as well. For stars, we are more interested in their birth and early development and in the late stages of their lives. We have a much better understanding of variable stars and are using studies of stellar variability to learn more about the structure of stars and about the behavior of stars in relatively close double star systems. The ability to get high resolution images of faint galaxies together with obsetrvations in wavelengths not observable from the ground as well as in radio wavelengths (Radio astronomy was just barely beginning when I started.) has given us much information about nearby galaxies and we are beginning to collect images and spectra of galaxies so distant that we see them as they were at less than one tenth of the present age of the universe. We are also getting information about the location of galaxies in large regions of space. The Cosmic Background Explorer (far infrared) settled the issue of whether the universe started with an hugh explosion (the Big Bang) or remained essentially the same throughout time. It started with an explosion. The second change is in instrumentation. As mentioned in the preceding answer, the possibility of observations from space has opened new windows on the universe but in all wavelengths, the most important change is the substitution of electronic detectors for photographic plates. These electronic detectors are much more sensitive and, since they detect individual photons, it is easy to deduce the brightness of the source observed. Together with advances in computers, they permit much more sophisticated processing of the observations so that more and more accurate deductions are possible. To a large extent, the push in electronic detectors came from the communication industry where they were first developed for television cameras. The infrared detectors (to the red of the colors the eye can see) were developed primarily by the military for night vision applications. For the X-ray region, the astronomers played a major role although the detectors are now being used to make medical X-ray exposures shorter and more accurate. Another major change is the development of electronic computers. When I graduated, there were only a few in the world. They were very limited in capability and difficult to use. They were so expensive, that it was several more years before a few astronomers were able to use them for very special computations. Today, computers not only make theoretical models that help us understand the physics of astronomical activity and process observations, but also control our instruments. Without computers, the space telescopes could not point at specific objects nor hold the pointing accurately and ground based telescopes could not use active optics to compensate for atmospheric disturbances and hence get good images of distant galaxies. We even use computers to combine the information from two or more telescopes to provide images with the detail that could be obtained from telescopes many yards or even miles in diameter. In the radio region, data from a Japanese satellite were combined with that from ground-based telescopes to give images equivalent to those from a telescope several times the earth's diameter.

[ NRoman/GSFC - 54 - 10:49:05 ]
RE: [Amanda] Hi again- If you were starting all over again in this day and age would you choose the same career? Why might you do differently today? What device can you give us on making career choices and following your passions?
Yes, if I were starting over, I think that I would still choose observational astronomy for a career. I probably would have had less temptation to go into management but I am not sure. The chance to map out a program in space astronomy that, starting from a clean slate, I felt would influence astronomy for many decades was very tempting. I probably would have reacted similarly to a similar opportunity if it existed today. However, I enjoyed both teaching and research and today would have had less reason to leave those activities. I also would have found computer science tempting. My advice is that if you are really sure you want to follow your passion in choosing a career, do it. However, find out enough about it to know the problems you will run into. You cannot predict the future so conditions may change greatly by the time you get into the field but you should be aware of potential difficulties and be prepared to persevere. I think that the worst fate you could have is to be stuck in a job you hate, no matter how well it pays. Conversely, the job you want may be hard to find and pay very little. There are other compensations in satisfaction. At present, the demand for research jobs in astronomy and in most physical sciences far exceeds the supply. Nevertheless, few scientists are unemployed and most make at least a respectable living. The primary requirements are to get a good foundation in your field, get as broad a foundation as you can, and be prepared to be flexible. When I went to NRL, 9 years after I graduated from college, I went into a field of astronomy that did not exist at the earlier time; when I joined NASA, it was to work in a field that did not exist when I received my Ph.D. 10 years earlier. Of course, I also changed from research to administration.

[ NRoman/GSFC - 56 - 11:29:48 ]
RE: [Kacy] I am doing a research project on Aerospace Engineering. Do you have any information or people I can contact at NASA about the field?
I have no suggestions about contacts for information on Aerospace Engineering but the NASA education office may be some help. For information on careers, try http://spacelink.nasa.gov/Instructional.Materials/Curriculum.Support/Careers/. Another URL that may be helpful is http://www.allstar.fiu.edu/. If neither of these give you what you want, you may wish to try the FAQ page of http://education.nasa.gov. Finally, you might write to the education office, by either e-mail or snail mail with your questions.

[ Oran/NASAChatHost - 57 - 11:40:40 ]
As a reminder, please share your thoughts about our forum with Nancy Roman at http://quest.arc.nasa.gov/qchats. We look forward to hearing from you.

[ NRoman/GSFC - 61 - 13:45:52 ]
RE: [Misti] I am doing a report on Women astronomers. Do you have any advice on what I should report on? I'd like to talk about you too is that alright?
The Astronomical Society of the Pacific (ASP) has a slide set on women astronomers. Each slide has a brief description. I do not see it in their current catalog but you could write to them or check their web site (http://www.aspsky.org). Their address is 390 Ashton Avenue, San Francisco, CA 94112. A few years ago, they devoted an issue of their magazine "Mercury" to women. This was the basis for the slide set. You may still be able to find the issue in the library. There is a book edited by Benjamin F. and Barbara S. Shearer called "Notable Women in the Physical Sciences" that contains moderately short biographies (2 - 5 pages) of many women astronomers. (published by Greenwood Press, Westport, Conn.) Again, check your library. Unfortunately, the biographies are arranged alphabetically rather than by subject area so you will have to page through the entire book to find the astronomers. Finally, a good encyclopedia, such as the Brittanica, should have some information on women in astronomy. You might also try the Web. I found that the ASP has a good site. It contains many links and also many references to information about individual women. The URL is: http://www.aspsky.org/education/womenast_bib.html. I do not mind your including me. Other women currently active include Vera Rubin, Sandra Faber, Lee Anne Wilson, Margaret Geller, Margaret Burbidge, Wendy Freeman, Heidi Hammel, Dorrit Hoffleit, and Rosemay Wyse. This list is some I can think of without a lot of consideration and certainly is not all-inclusive.

[ NRoman/GSFC - 63 - 13:47:00 ]
RE: [Clarissa] I know you have addressed the gender issues in some of your earlier chats, but I am also wondering if there are ever age issues - new or younger people thinking they have more modern ideas, etc. than you.
I am sure that there are age issues but I do not think I have run into them. I was let go from my last job but I think that this resulted from a personality conflict rather than age. I am now enjoying the change to teaching and volunteer activities. Most astronomers continue in the field as long as they are capable although those in universities usually retire so that they can devote their time to research rather than teaching. I mentioned Dorrit Hoffleit among astronomers active currently in an earlier answer. She is 91 or 92. Although she is not paid, she is still working every day. Charlotte Sitterly, who died at 93 a few years ago, was doing regular volunteer work at the Naval Research Laboratory up to the week she died.

[ NRoman/GSFC - 64 - 13:48:09 ]
RE: [Rita] I am a 32 year old nontradtional college student, with great interest in science. I'm in the process of working a science project in reference to Jupiter. I would like for the project to be a sucess, however I haven't a clue on making a project about Jupiter. Can you please me some suggestions.
Without more information about the type of project you wish to pursue and your level of expertise, it is difficult to suggest a specific project. One possibility is to study the various pictures of Jupiter taken not only by the various planetary probes that have visited the planet but also by Hubble and various ground-based telescopes. Most of these are available on the Web. From the pictures, see what you can learn. For example, does the cloud structure on Jupiter change with time? How? What other changes do you notice. Why are the infrared pictures different from the visible pictures? Then depending on how much time you have, you can investigate further the various phenomena you observe. For example, what is known about the atmospheric circulation on Jupiter? Can it tell us anything about the atmospheres on other planets? In what ways is it similar to or different from the atmosphere of the earth? You may want to look into the history of what we know about Jupiter, starting with Galileo's observations and including major discoveries since. What do we know about the radio emission on Jupiter and what does it tell us? In what ways is the magnetic field of Jupiter important? Do you want to look in some detail at the satellites of Jupiter? At its ring? You might try the Web for sources of other information. I found a book by Ruth Beebe. It was published in 1997 so will not have much about the Galileo results but should be good for the history as the author is an expert on the planets.

[ NRoman/GSFC - 68 - 13:50:46 ]
RE: [MsWoodsclass/SC] How do you keep current on all the new technologies? Do you read , listen to lectures...?
I certainly do not pretend to keep current in any detail on all of the new technologies but I do try to keep up with the general developments. I read and attend lectures. There are a few Web sites I monitor also but some are better for pictures than for new information.

[ NRoman/GSFC - 69 - 13:51:34 ]
RE: [MsWoodsclass/SC] Ho wmuch involvement did you have with Chandra? Do you know or did you work with Eileen Collins? Thank you for answering our questions. We have enjoyed reading the other responses.
No. I never worked with Eileen Collins. In fact, I have not met her. I knew some of the earlier astronauts but have been away from NASA employment long enough that I have had no content with the newer ones. I had know several of the scientist astronauts before they joined NASA. I was involved with Chandra during its very early development but most occurred while I had little responsibility for X-ray astronomy.

[ NRoman/GSFC - 71 - 13:54:31 ]
RE: [Stephanie] Does your work involve morso physics or chemistry? Which do you like better? Why?
My work involved more physics than chemistry. In fact, I did not study much chemistry. If I were in college today, I would probably take more chemistry, including organic chemistry. The latter has become much more important in astronomy than it was 50 years ago. Not only are the planets full of organic molecules but interstellar space contains at least 100 different ones. I would probably also pay more attention to molecular spectroscopy. I did study that but did not use it enough to really feel comfortable.

[ NRoman/GSFC - 79 - 11:39:45 ]
RE: [Stephanie] How did neutrinos help form the sun?
I do not know that neutrinos did help form the sun. I have never seen that suggested. However, the sun creates neutrinos as it transforms hydrogen into helium. Neutrinos pose an riddle for astronomers because we do not observe as many neutrinos from the sun as theory tells us we should expect.

[ NRoman/GSFC - 80 - 11:40:49 ]
RE: [Misti] How did you feel when people told you that the feild that you wanted to go into wasn't for you.
The only thing I remember about people telling me, both overtly and subtly, that astronomy was not a field for a woman is that I knew that that was what I wanted to do. I was stubborn.

[ NRoman/GSFC - 81 - 11:41:30 ]
RE: [Lee] Do you beleive that a mass coronal mass ejection from the earths sun could possibly externimate life on our planet?
No. Coronal mass ejections from the sun are powerful enough by the time they reach the vicinity of the earth to affect our ionosphere and hence, at times, radio communication and even power grids but they are not strong enough to affect life below the protecting atmosphere. Eventually (in say, 5 billion years), however, the sun will run out of fuel. When it does, before it settles down into a cooling white dwarf, it will expand to include the orbit of the earth and possibly even Mars. At that time, any life remaining on the earth will be extinguished.