Chat with Yvonne Pendleton 2-25-97

Hi! Yvonne here.
I just finished teaching my inroductory astronomy class (at Santa Clara
University)which I teach once a year in addition to my regular NASA job. 

Does NASA let you take time off to teach?

NASA let's me take time off to teach because this is another aspect of
public outreach that is important for NASA scientists to do. I really love
teaching, and I've found I'm kind of good at it. 

Hey everyone!! And Hello to you Yvonne!! Could you tell all of us Women of
NASA participants a little more about your job?

My job consists of writing proposals to get observing time to study
interstellar dust and primitive solar system bodies. If successful in
getting telescope time, I go to the telescope and make observations. Then
I come back to Ames and use computer models to understand the physics that
must produce the observations. Finally, I write papers about the results.
I go to the telescopes (usually in Hawaii) several times a year. I write
about 4 or 5 papers a year.

Did you ever feel like an outcast because most of the people in science
were men? How did you overcome this? 

Oh sure, I've felt like an outcast or a fifth wheel at times. In my
college classes at GeorgiaTech (I was the only woman in aerospace
engineering) the instructor would start to tell an off color joke, look
down at me, and say, "Oh- I guess I can't finish this now".

Can you tell us something about the comet Hal Bopp? Why is it named that?

Hi Sheanna, the comet is named after the two people who discovered it. Mr.
Hale and Mr. Bopp.

When was it discovered and how?

Hale-Bopp (there is an e on the end of the first name) was discovered
about a year ago. It is a big comet, so that even though it won't come as
close as Comet Hyakutake did, it will appear as brigh

Are you doing an observations on Hal Bopp?

I am part of a team that is observing Hale Bopp. I will be working on the
data soon, but I haven't seen it yet. I will study the organic material
(carbon compounds) to see what comets are made of.

What does observing a comet tell us?

Observing a comet tells us about the material that the solar system formed
out of. The comets are "unprocessed", that is, they haven't been exposed
to the Sun's radiation as much as the planets have.

What is the difference between comets, meteors, and asteroids?

Meteors are the left over debris from comets. The Earth, on its orbit
around the Sun, passes through these debris (or left-over) clouds from
comets, and we see meteor showers. Asteroids are rocky bodies inside the
Solar System (mostly between Mars and Jupiter). Comets are icy bodies that
reside far away in the solar system where it is cold. When they come in
close to the Sun, the ice melts. Pieces of asteroids that fall to the
Earth are called meteorites.

Where will you be observing the comet and what type of instruments?

Our team observes the comet from Hawaii with the NASA infrared telescope
(3 meter diameter). I will be in Hawaii , on Mauna Kea where the
telescopes are, to use a different telescope in April. I will be studying
other comets.

Could the HalBopp comet melt?

Yes, some of the ices will evaporate as the comet comes closer to the Sun.

How long will this comet be around and will we notice any changes if it
melts?

We will see the tail develop further as the ices continue to evaporate.
The comet will be visible, but become less bright, during April and May.
Closest approach is around March 22.

So do most comets melt then when they get close to earch? How long will
Hale Bopp be around?

As comets come closer to the Sun, they do heat up and the ice sublimes.
That means it doesn't really melt- it goes directly from a solid to a gas.
Hale Bopp will be around for a few months, then its orbit will take it far
out in the Solar System again.

When will Hale Bopp melt completely and how do you know this?

Hale Bopp will not melt completely. It will travel far enough away from
the Sun so that it will stop "melting" and it will no longer have a tail.
We know the orbit very precisely based on measurements we have already.
All objects in our Solar System orbit the Sun in an elliptical pattern, so
when you know a few points on the ellipse, you know the rest of it.

**********

Do you make other observations besides comets?

Yes! In fact, I really study interstellar dust and star formation most of
the time.

Do the telescopes you work on belone to NASA and if so how come you have
to ask to use them?

Some of the telescopes I use do belong to NASA. I have to compete with
many other astronomers who also want to use the telescopes. For every
proposal that is selected, 3 others (about) are turned down.

Are all of the astronomers who use the telescopes from NASA? Who do you
share your research with?

The astronomers come from universities and research labs around the world.
We all compete for the observing time. The best projects get selected.

Who owns the telescopes and who pays to maintain them?

Several countries may go in together to build and maintain a telescope, or
several universities might, or one big institution likke NASA. Then, a
certain percentage of the observing time goes to the astronomers from
those countries, universities, etc. and the rest is up for grabs to
all astronomers. They still have to compete with scientifically sound
proposals.

Why are most of the telescopes in Hawaii? 

Hawaii is a good place because the atmosphere is very dry and calm. The
mountain is nearly 14000 feet high, so we can get up above most of the
atmosphere that interferes with light from the stars. However, the
atmosphere that is still there distorts the light from comets and the
stars because water vapor and turbulence blur the telescopic image.

Do you ever use the Hubble telescope? Will this by used for observing Hale
Bopp? What is it usually used for?

I use Hubble occassionally. It is a great telescope.

**********

Do you think it was hard to get back into the work force after take 2
years off?

I had continued to work part time during the two years, but when I was
ready to go back to full time it was hard to get a full time position
again. I ended up working full time to save my career, but I was only paid
at a part time level for another 2 years.

What advice could you offer to fourth grade students?

Hi Phoenix, my daughter is a fourth grader. It is a great time to explore
the web and the world of computers. You can learn a lot by doing so.

**********

What do you think about life on Mars?

Hi Tim, I think life could have started on Mars and come to Earth. I don't
think the martian meteorite evidence for fossil life is holding up though.

**********

What is your progress on making a new space station?

As for the space station, it is coming along as I understand it. I am
actually not a very strong proponent of it though. I think the money could
be better spent on spacecraft to visit the planets, comets, etc.

**********

What advise could you give to a teenage girl who would like to enter the
aerospace field?

I'd advise her to study math and science and build up her confidence in
those fields. She will need to rely on that self-confidence when the
system gives her a hard time, and that will probably happen occassionally.
It really isn't an awful situation, though. It is getting better all the
time.

Did you take any time off to have kids?

I took 4 months off when my daughter was born, and I worked part time for
2 years after my son was born.

We are trying to find a web site that encourages women to go into the
fields of math and science. Do you know of any? 

There must be web sites that encourage women to go into math and science.
There is a newsletter called imagine that has web sites listed in it. You
can find the link to that from my web page for my astronomy class. Go to
prometheus.arc.nasa.gov/users/yvonne

Here is the address for the Imagine
newsletter:http://jhunix.hcf.jhu.edu/~setmentr/links.html

There are other web sites that encourage women to go into math and
science. There is a newsletter called imagine that has web sites listed in
it. You can find the link to that from my web page for my astronomy class.
Go to prometheus.arc.nasa.gov/users/yvonne

Yvonne, we are running a special project here at my school. Thankyou for
taking the time to answer our questions. you are an inspiration to us.
Thankyou