April 2, 2001 (1:00 p.m.-1:45 p.m.)

Jack Dunn from the University of Nebraska in Lincoln and the Mueller Planetarium Coordinator chats with several classroom groups representing Grand Island Public Schools, Omaha Public Schools, and Westside Community Schools.



Welcome to eSchool!

Tom Albertsen: http://communitydisc.westside66.org

Cindy Mangers: http://spacelaser.com

Tom Albertsen: Hi, Cindy! Glad to see your computer will push web pages. I know Sue and Carol were having

trouble on someone else's computer in Grand Island.

Colette deFrey: Hi, I see that Cindy, T.J., Rosy, Daren and Deb are present and accounted for!

Colette deFrey: We are waiting for Betsy Campbell and Donna Wroten

Darren Folchert: Hi Colette and Tom

Colette deFrey: and, of course, Dr. Jack Dunn

Colette deFrey: Hi, Daren!

Jack Dunn: www.spacelaser.com/jdunn.html

Tom Albertsen: Hi, Daren. Sorry about the spelling on your login name!

Colette deFrey: We have copies of this morning's chat for all of you that we will be sending! You will also get a

copy of today's

TJ Jensen: TJ's students are on-line and ready to go...Katie's students will be here soon.

Colette deFrey: I see Jack Dunn has joined us from the Mueller Planetarium and has pushed his website!

Jack Dunn: Erik and I are back with lunch and ready to go

Colette deFrey: Hello, Jack! We are waiting for two more groups. We officially start at 1 pm, so enjoy your


Colette deFrey: IMPORTANT INFORMATION. PLEASE READ!Colette de Frey is the moderator for the chat.

She will tell each group when to enter a new question. DO NOT ENTER A QUESTION UNTIL YOU ARE TOLD


Colette deFrey: OK, IS EVERYONE READY???? We will start with Cindy Mangers in Grand Island. Please

enter a question for Jack!

Jack Dunn: We're ready here

Colette deFrey: OK, we need a question from Cindy's group - Betsy's group will be second.

Jack Dunn: Note that the webpage I'm entering is a jumping off point for you to check out some things.

Jack Dunn: www.spacelaser.com/jdunn.html

Colette deFrey: OK, Betsy's group - Go for it!

Betsy Campbell: How many miles away can the Hubble Telescope see?

Jack Dunn: Forget miles. Remember the distances in space are measured in light years. A light year is about

6 trillion miles. Some of the most distant objects Hubble observes are 10 billion light years. You see how the

numbers get so big it doesn't mean much any more. As a friend of mine once said: "it's too far to walk."

Cindy Mangers: How far can the hubble "see" in light years? from Mangers-JOhnson

Colette deFrey: Here's Cindy - Take her question next

Colette deFrey: OOPS , this was already answered

Colette deFrey: Let's go with Tj Jensen's group

Jack Dunn: Again the most distant objects are somewhere in the 10-12 billion light year range. But seeing

isn't quite like what you are thinking

Colette deFrey: TJ Jensen group???? Are you there?

TJ Jensen: How does pollution effect the study of astronomy?

Colette deFrey: Good question!

Colette deFrey: It will take Jack a moment or two to respond, so be patient!

Donna Wroten: How old were you wanted to be a astronimer


Jack Dunn: Pollution in the sense of man-made pollution as most people think of it doesn't have much effect.

Pollution if you want to call it that, by nature can really effect it. A volcanic eruption throws huge amounts of

dust in the atmosphere and makes seeing more difficult. On the other hand human "light pollution" is a real

pain. there is far too much light wasted and energy wasted with lights on earth that don't improve safety.

Hubble is above the atmosphere so it is not affected by this pollution.

Colette deFrey: How does pollution effect the study of astronomy, Jack?

Colette deFrey: OK, Let's go with a question from Katie Sindt

Colette deFrey: OK, let's go with Rosy Conrad's group

katie sindt: What do you think the study of astronomy will look like100 years from now?

Jack Dunn: http://amazing-space.stsci.edu

Jack Dunn: Just gave you a great site for kids at space telescope institute

Tammy Carson: Hi! My name is Alia Conley, and her is my question, why is the Hubble able to see space so

clearer than the satellites Explorer One and Explorer Two?

Colette deFrey: what will the study of astronomy look like 100 years from now is the question

Jack Dunn: 100 years from now - that's a tough question. I would say that we will have more orbiting

observatories. Whether or not we will go back to the Moon or to Mars - we might have observing sites there.

And yes, I believe we should go back to the Moon and we should send humans to Mars.

Colette deFrey: Now let's go with the Tammy Carson question

Jack Dunn: www.spacelaser.com/jdunn.html

Colette deFrey: why is the Hubble able to see space so much clearer than Explorer 1 or2?

Jack Dunn: Back to Tammy's question. The Explorer series were very early satellites. They weren't

observatories with actual

Jack Dunn: telescopes

Colette deFrey: OK, Donna Wroten's kids

Tammy Carson: Alia: What is the best picture that the Hubble has sent down?

Colette deFrey: Ignore that last question. Go with Donna's

Colette deFrey: Donna are you there?

Donna Wroten: yes

Colette deFrey: Please ask a question of Jack

Colette deFrey: Daren Folchert's group at Hillside is next - get ready!

Donna Wroten: How old were you when you wanted to be an astronomer

Colette deFrey: OK, Daren's group - go for it!



Jack Dunn: Back to the question of age. I got interested in astronomy when I was in college. Yes I always

had an interest in

Donna Wroten: Hubble

Jack Dunn: science. And I refer to my self as an astronomy educator and writer

Colette deFrey: Now back to Daren's question

Donna Wroten: hi?

Jack Dunn: Now to Darren. How many hours have you got. Hubble has take thousands of images.

Colette deFrey: OK, Deb Harkless's students may enter a question.

Deb Harkless: How can humans grasp/understand the immense size of the universe, and how small the earth

is? (Kayla, Irma, Kursten--Lexington)

Jack Dunn: Got to the Amazing Space site or the main hubble site (I'll take you there in a minute) and you can

see plenty

Jack Dunn: http://hublle.stsci.edu

Donna Wroten: I will ask old is the Hubble

Colette deFrey: http://hubble.stsci.edu

Donna Wroten: I mean, how old is it?


Jack Dunn: I need that last question again .


Deb Harkless: How can humans grasp/understand the immense size of the universe, and how small the earth

is? (Kayla, Irma, Kursten--Lexington)

Renee Kent: With the new Space Telescope Imaging Spectagraph, what progress has been made in the hunt

for giant black holes? Jack do you know that answer?

Donna Wroten: sorry

Renee Kent: With the new Space Telescope Imaging Spectagraph, what progress has been made in the hunt

for giant black holes? Jack do you know that answer?

Jack Dunn: Now there's a real question that I think is possibly unanswerable. If you look at the famous

Hubble Deep Field photograph and realize that this is a picture of an area less than the size of your little

finger's nail and realize that those are all galaxies in the picture, each one with billions of stars. Maybe that's

a start


jack ccan handle only one question at at time.

Colette deFrey: OK, Cindy - go for a new question

Colette deFrey: While students are waiting for their turn, it might be a good idea to have the question already

typed in. Just don't hit return until you are given the go-ahead.

Colette deFrey: Cindy - are you there?

Colette deFrey: Betsy - your group may enter a question

Betsy Campbell: Have you found any new planets?

Donna Wroten: Okay

Cindy Mangers: How far is the farthest picture the Hubble has ever taken?

Jack Dunn: One thing I think that needs to be mentioned is how science really works. An observer decides to

study a question.Then takes all kinds of data, then works to see what that data tells him or her and comes to

conclusions.It isn't that random.

Jack Dunn: Collete - which do I take

Colette deFrey: Go with Betsy - any new planets?

Jack Dunn: Not what you or I would call planets. Really the Hubble was not designed as a scope for the

planets although

Jack Dunn: it has been used to photograph some of them. What we keep finding are small asteroid =sized

things. But those are found with other scopes. Now I meant planets in OUR solar system. Yes, the hubble

has helped identify planets around other stars. But again it doesn't really photograph them.

Colette deFrey: How far is the farthest picture the Hubble has ever taken?

Jack Dunn: The problem is that in one picture there may be many objects - some closer and some further.

Generally, the Hubble has been used to receive information (in some cases not pictures as you know them)

from objects 12-14 billion light years away.

Colette deFrey: T.J. Jensen's kids are up now!

Sue Little: How are orbit height and speed determined?

Jack Dunn: www.spacelaser.com/jdunn.html

Colette deFrey: Go with Sue's question, Jack

Jack Dunn: Orbit height of Hubble or what?

Donna Wroten: Have you ever seen a UFO on the Hubble? Have you ever construct something bigger than

Hubbles? \

Jack Dunn: There are basic orbital mechanics which regulate speed, height and the orbit of any body in

space. These are based on Kepler's laws of motion.

Colette deFrey: Katie Sindt is next

sue rasmussen: Do you know where the Hubble Telescope currently is above the Earth?

Jack Dunn: I believe I can send you to a website that will give you that information

Jack Dunn: www.heavensabove.com

Jack Dunn: www.heavens-above.com

Colette deFrey: OK Rosy Conrad's kids are next

Jack Dunn: Well if it ever goes there, the heaven-above site allows you to find and track all sorts of objects

Rosy Conrad: Hi, I'm Sam. I am NOT Rosy Conrad. I heard that Hubble had problems in it's first year. What

really happened?

Jack Dunn: Basically, the Hubble's mirror was ground to the wrong figure - that is the shape of the surface

was not correct. It was an error at the contractor. Hubble was still usable however with slight correction

from computers. Then astronauts went up to Hubble with the Space Shuttle and installed a corrector plate

which fixed the mirror problem

Colette deFrey: Daren - Your group is next

Jack Dunn: www.spacelaser.com/jdunn.html



Tammy Kenton: What new and exiting information has the Hubble Deep field discovered about other galexies?

Colette deFrey: Just answer the first one, Jack!

Jack Dunn: Darren: Again, the hubble really is not a telescope for our solar system. Some work has been

done and some images taken, such as when the comet Shoemaker-Levy 9 hit Jupiter. But most of this has

just spirred on ground-based observatories

Colette deFrey: OK, Deb Harkless's students are next

Jack Dunn: www.astropix.com/INDEX.HTM

Deb Harkless2: In the future would anyone be able to reach Pluto? (from: Irma, Kursten,& Kayla -- Lexington)

Jack Dunn: It jumped out with that website so you'll have to ask last question again. The site I sent you to

has pictures taken from earth by an amateur astronomer to show you that not just hubble sees great things

Jack Dunn: www.spacelaser.com/jdunn.html

Colette deFrey: In the future, woud anyone be able to reach Pluto?

Deb Harkless2: In the future would anyone be able to reach Pluto? (from: Irma, Kursten,& Kayla --


Jack Dunn: Sure you can reach it. But are you talking a landing or what?

Colette deFrey: Cindy - your group is next

Deb Harkless2: a human landing on Pluto.

Jack Dunn: Remember that Pluto is in our solar system - a lot closer than most of the things imaged by the

Hubble. But still a long way away as far as a planet. The trip at our current speeds would take many years.

We are going to have to come up with new types of engines to get there in any reasonable time.

Colette deFrey: Cindy - where is your question?

Jack Dunn: By the way - a trip to Mars at current speeds would take over 2 years round trip

Colette deFrey: Betsy - go with a question from your kids

Dale Mette: (Landon) What caused the flaw in the hubble's mirrior???

Jack Dunn: Stupid human error

Colette deFrey: Great! How about TJ

TJ Jensen: Edwin P. Hubble thought of the idea for the Hubble in 1946, why wasn't it made then?

Betsy Campbell: What are you working on right now with the information you are gathering with the Hubble?

Colette deFrey: Go with TJ's question then Betsy

Jack Dunn: We didn't even have the ability to put anything in orbit until the 1960's and the weight of the

Hubble is such

Jack Dunn: it would not have been able to send up till the Saturn V rocket was invented. But all that would be

of no use because the technology to get Hubble's information to earth didn't come along until 20 years later.

Colette deFrey: What are you working on now with the info from the Hubble?

Jack Dunn: I'm not working on anything except getting the information to the public. i'm not an astronomy


Colette deFrey: OK, let's go with Katie's group

tina rickett: Why does the HST need to be brought back down to Earth?

Jack Dunn: Eventually everything in orbit will fall to Earth unless a rocket boosts the orbit. All orbits "decay"

which means

Jack Dunn: friction will eventually slow them and they burn up in the atmosphere

Colette deFrey: Let's go with Daren's group at Hillside next

Jack Dunn: Be sure and visit the links I have put on the special webpage for you. I put in links to a student

who worked here

Colette deFrey: Yes, everyone will be getting a copy of the chat with the URL's so you can visit them later!

Jack Dunn: 20 years ago and now designed the optics of two major observatories - the Gemini Telescope


Cindy Mangers: We were able to get the images now and they are wonderful. Thank you.

Colette deFrey: OK, let's go with Deb Harkless' s kids in Lexington

Deb Harkless: If you had the chance to be famous for visiting Pluto or for inventing the Hubble, which would

you choose, and why? (Kursten, Irma, Kayla--Lexington)

Jack Dunn: I wouldn't want to go to Pluto and no one person invented the Hubble.

Jack Dunn: But going to Mars would be great

Colette deFrey: Thank you, Dr. Jack Dunn , for chatting with us today!

Tammy Carson: Alia Conley:Who were the people that fixed the Hubble? What were their names?

Colette deFrey: We've got to bring this chat to an end now

Colette deFrey: Thanks you for spending time with us!

Betsy Campbell: Goodbye, and thanks!

Colette deFrey: And for including the great URL's!

Tammy Carson: thankyou dr,dunn!

Rosy Conrad: Hi, It's me again! Sam. Here is my question. As the Big Bang could be similar to a conventional

blast, and therefore the universe formed around it, how is it possible to say there is no center of the


Dale Mette: BYE !

Pam Buchholz: Swanson appreciates all efforts to make this possible!

Tammy Carson: see ya!

Donna Wroten: seeya

Colette deFrey: So long, Jack!

Colette deFrey: Remember, to sign out, go to FILE and down to QUIT!

Deb Harkless: bye


Dale Mette: I greatly appriciated you visting us!

Tammy Carson: Have a nice day!

Colette deFrey: Thanks, teachers and students!

Jack Dunn: check out our site at www.neb-star.org and also go to the planetarium web site and join us for

Astronomy Day 2001 with Nagin Cox of JPL as a speaker

Tom Albertsen: thanks to all of you for your participation. It is always great to see technology being put to

good use!

Tammy Carson: byebye

Jack Dunn: Clear Skies - bye

Donna Wroten: good bye

Dale Mette: bye on more time

Deb Harkless2: Thanks for sharing your expertise!


Deb Harkless: good bye

Return to the Chat Home Page