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Welcome to the Webcast for the Cratering the Moon Challenge
Wednesday, March 5, 2008
See more information on the Challenge

Transcript of webcast:

>> Hello.
Welcome to the cratering the moon challenge.
This is the first Quest challenge associated with NASA's LCROSS mission to the moon.
We're coming live to you from California.
Tony, can you tell us what is your job title?

>> I am the principal investigator, chief scientist over the mission and also the payload manager.

>> Jennifer, what is your title?

>> I'm working with Tony on the science team and the payload team and also serving as the observation mediator.

>> We have a short video for you that will give you the details of this mission.
Let's watch the video now.


Lunar CRater Observation and Sensing Satellite (LCROSS): A First Step in the Return to the Moon Video Transcript:

S. Pete Worden, Center Director, NASA Ames.
More than 35 years have passed since humans last walked on the Moon. NASA’s current mission is to once again take a giant leap for mankind by establishing a human outpost on the Moon. To pave the way, robotic missions surveying the Moon will launch in late 2008.

Dan Andrews: Project Manager, LCROSS
The Lunar Reconnaissance Orbiter or LRO and Lunar Crater Observation and Sensing Satellite or LCROSS will launch together on an Atlas-Five rocket.

Anthony Colaprete, Principal Investigator, LCROSS
Their mission is to provide critical information to NASA as it plans our future on the Moon.

Dan Andrews:
We here at NASA Ames Research Center are extremely excited to be designing and conducting the LCROSS mission. The goal is to determine if water, perhaps in the form of ice or hydrated minerals, exists inside a permanently shadowed crater on the South Pole of the Moon.

Mark Shirley, Software Lead, LCROSS
Water is an extremely valuable and versatile resource. Water can be split into hydrogen for rocket fuel and oxygen for breathing. It can be mixed with moondust to make concrete used in building shelters. It also makes an excellent shield to protect against radiation.

Since any ice on the Moon might be buried underneath a layer of rock and dust, we need some method of getting the ice out into the open and detecting it.

Jennifer Heldmann, Co-Investigator, LCROSS:
The LCROSS mission accomplishes this with two space vehicles. The Centaur upper stage of our Moon rocket will be used as a 2200-kilogram kinetic impactor, excavating a crater approximately 20 meters wide and almost 3 meters deep. More than 250 metric tons of lunar dust will be lofted above the surface of the Moon.

Dan Andrews:
The Shepherding Spacecraft, built by our partner Northrop Grumman, guides the Centaur upper stage to the target. It also carries cameras, spectrometers and a photometer to analyze the debris plume to look for the presence of water vapor, ice, hydrocarbons, and hydrogen, which is one of components of water.

Anthony Colaprete:
The science instruments onboard the LCROSS spacecraft cover an extremely wide spectrum. We have spectrometers that can see organics, hydrocarbons, and byproducts of water ice. We also have infrared cameras that can see hydrated minerals, water ice and water vapor. In addition to telling us if water exists on the Moon, the science that comes out of this data will be used for many years beyond the LCROSS mission.

Mark Shirley:
Two hours after launch, LRO will separate from LCROSS and continue on its way to the Moon. Five days after launch, LCROSS and the attached Centaur will execute a fly-by of the Moon. They will then enter into several large, looping orbits around the Earth for the next few months of the mission. We will use this time to check instrument calibration and refine our trajectory for lunar impact.

Dan Andrews:
About seven hours before impact, the Shepherding Spacecraft will separate from the Centaur and position itself to observe the impact at the south pole of the Moon. For the next four minutes after the impact of the Centaur, we will receive real-time data as the Shepherding Spacecraft flies through the plume and scans the ejecta for signs of water.

Anthonly Colaprete:
The Shepherding Spacecraft will then impact the Moon, creating a second plume of lunar dust.

Jennifer Heldmann:
Both impacts will be closely observed by professional astronomers on the Earth, using some of the world’s greatest observatories. We also believe there is a chance that the impact plume may be visible in 10 to 12 inch amateur telescopes. We are encouraging both professional and backyard astronomers to participate and contribute their observations to this exciting mission.

Dan Andrews:
We are at a key point in human history. Humanity is preparing for its next stage in our development and that stage is settling the solar system.

Tony Colarete:
As NASA moves forward with our exploration programs, one of the most important things we need to figure out is how people can live for long periods, and eventually permanently, off the Earth.

Mark Shirley:
If we can identify water ice at the poles of the Moon, we can use that water to live off the land.

Dan Andrews:
We are excited, proud and honored that the LCROSS mission has been chosen to be a first step on our long journey as humankind takes its next giant leap back to the Moon, to Mars and beyond.

-------------------------------------end of video--------------------------------

>> This certainly sounds like an exciting mission.
Our chat room is now open so if you have questions you would like to ask our scientists here, this would be a great time to get into the chat room.

>> Speaking of chat rooms, Brian, I have a question from -- I believe it's com school gifted program.
They ask, what are the professional backgrounds of people working on LCROSS?

>> Professional backgrounds.
Well, after college I came straight to NASA.
So while in college I worked on a variety of projects through the grant college and I worked on space shuttle projects, missions and small satellite missions, developing instrumentation for those.
Prior to that I worked in a restaurant and prior to that I worked in a pet store and so on and so forth.
Once I came to NASA, as soon as I graduated school, I knew I wanted to work for NASA.
I came to NASA and in the year 2000 and I've been here ever since.

>> Well, in middle school and in high school, I took a lot of math and science and when I went to college, I took a lot of astronomy and geology and physics.
And then I went on to graduate school and got a Ph.D. in science and along the way did a lot of internships and I went to camp and things like this challenge.

>> The next generation of scientists are participating in this challenges right now.

>> I think they probably are.

>> We got a question about the same subject which asks, what is it like to work at NASA?
This is from angelo.

>> I think it's really fun to work with NASA.
It's a lot of hard work.
You have to work really hard and study math and study science but every day when I come in, I'm doing something different.
Whether it's working on the spacecraft or analyzing data that just came back to Mars or planning new missions so every day is something a little bit different and we're always working on neat projects, advancing in science and explorations.
It's a lot of work to get there and a lot of school to get there but worth it.

>> I would say the same thing.
It's something I always dreamed for myself, always dreamed of doing.
It took a lot of work, a lot of studying.
It was worth it.
Once you get here, you're immersed in this incredible group of people who all feel the same way as you do, who want to explore the universe, understand where we are and get to view some really incredible things.
Building rockets and sending them to other rockets is fun, looking at information that comes back from the projects, understanding the world and the solar system and the universe in general.
I can't imagine a funer thing to do.
It is a lot of work to get here and while here it is a lot of work but it's -- I think the old saying is if you do what you love, you never work a day in your life.
That's how I feel it right now.
It's not work.
It's just fun.

>> Speaking of things we love, we have in front of us a model and perhaps we could talk about this a little bit.
What are we looking at here?

>> This is a scale model of the LCROSS system, the impactor and the shepherding spacecraft.
This long white part here with the rocket engine on the bottom is the upper stage of the rocket that sends LCROSS and it's the primary mission which is the lunar Reconnaissance orbiter to the moon.
Once in space, L.R.O. goes on its way to the moon.
LCROSS, this little spacecraft here acts as a tug boat.
It holds on to the upper stages of the rocket which would otherwise be space junk.
This would be burned up in the atmosphere over the Pacific normally, just a great big hollow cylinder.
We get rid of all of the excess fuel in it and we haul it around the earth for about three months until it's ready to impact the moon.
At that time, this part of the spacecraft separates from the impactor, turns the instruments to it, this part right here heads to the moon, impacts, while this part observes.
This part also impacts four minutes later after the primary section impacts.
This part here weighs about 2200 kilograms.
It will be moving 2 1/2 kilometers per second.
Twice the speed of a bullet.

>> What is something that we can think about that has that kind of mass?
What's something we might be familiar with?

>> Sort of the mass you're talking about.

>> A large S.U.V. but moving at faster than the speed of a bullet.

>> About twice the speed of a bullet.

>> A quick question from -- let's see. It's ibra.
I'm kind of confused about how we're going to find water on the moon.

>> It's complicated process that actually we've undertaken to discover the water.
We look for it. And honestly, we don't know that it's water. We see hydrogen.
Previous missions have detected this enhancement of hydrogen.
A lot of people speculate and believe it's hydrogen, a natural component of water, is what we're detecting in the moon.
LCROSS, one of the primary purposes is to confirm or identify that this hydrogen we see is actually water, water ice.
The way is that it's done is the large impact of this part here hits the shadowed region of the crater where we think water could exist.
That throws debris up into sunlight.
It's in a dark crater.
That's the trick.
We're looking at something that doesn't get sunlight.
How do you do that?
How do you look at something you can't see?
We use the impactor to lift the material up so we can see it.
Once we can see it, we have a sweep of instruments on this part of the shepherding spacecraft that will observe the ejected dirt, looking at it for the signs of water ice, water vapor and other possible combinations of minerals that could contain hydrogen.
The instruments are cameras and spectrometers.
That separates things in different colors.
Water vapor has unique signatures in different colors, like fingerprints.
When we look at the -- we can look for the fingerprints in our instrumentation and in the ejected clouds and determine if there's water ice there in that material.
And actually, we have a slide that I can show you from our instrument that shows a picture of me from our five cameras on the spacecraft in five different wave lengths and it illustrates nicely what I was just describing here.
These are our five cameras on the spacecraft and that's me in our clean room.
We have some pictures of us, jen and I working in the clean room, testing instruments before they're delivered to the spacecraft recently.
On the side there that is tilted, that's a visible camera.
It's a color camera, similar to your camcorder that gives us context.
This tells you where you're going.
You can see me as I look, hopefully.
The other camera on the top there, nir one and nir two, those are infrared cameras.
They look at wave lengths or colors just beyond the visible spectrum.
You can see on one of the images, both images my hair is very light which means it's very reflective so you can see my face.
It's very dark in one and not so dark in the other.
The one where my face is dark, that camera has been tuned to be very sensitive to the fingerprint of water.
So you can see actually the perspiration of water in my skin, making my face look dark as opposed to the camera two which is not.
We essentially accentuate where the water is in that scene.
The two images down at the bottom are me in the infrared or thermal wave length.
That's my heat coming up.
You can see my nose is green which means it's cooler than my cheeks and forehead and mouth area.
Two different wave lengths again, one being tuned to water vapor so we'll be able to see if there's water vapor.
This is an example how you can look at different colors of light and even looking at temperatures which is also considered a color of light and determine a lot about what it is you're seeing.

>> I have another question coming in here about -- from, again, the com school gifted program.
They want to know how far have you come on the assembling of the impactor and do you have any diagrams of it that we would be able to see?
The model helps.

>> we have the model.
I don't know that we have any slides with diagrams of the impactor but they can go to our website and there are, I believe, diagrams there that they can look at and actually some presentations that jen mentions that they can download and look at that give all of the details you want.
Where we are right now is we are building this part right here, the shepherding spacecraft is being built.
It's kind of hard to see here but the shepherding spacecraft is a mounting ring that has panels all around it.
Each panel contains part of the spacecraft like the battery, the solar panel.
This big one is the solar panel.
One of those contains the payload that I was just describing.
Here at NASA ames, we pulled together and built a payload and about a month and a half ago we sent it to Los Angeles and they are putting it onto the spacecraft.
So the spacecraft is being built right now.
We will be ready to test the spacecraft fully built in about a month's time.
We deliver to the Kennedy space center for integration onto the rocket and the other spacecraft that flies with it at the end of July.
So early August we'll be actually done building our spacecraft and ready to go for launch in late October of this year.

>> OK.

>> One of the questions that we hear a lot is, what will be the impact -- what will be the effect on the moon if there's impact?
What are we going to do this with?
How will it be different after you hit it?

>> You can see the picture behind us.
That's the picture of the moon made from the radar observation from the earth.
You see lots of holes in it and that's from the barrage of impact that's occurred over the last four billion years that the surface of the moon has been as it is today.
LCROSS will make a similar impact, a similar crater but not observable at this scale.
The size of the impact that LCROSS mission will make is about 20 meters across.
About the size of a tennis court.
That may sound big but this crater right here, this is one of our potential target craters.
This crater here, this is shoemaker.
It's about 35 kilometers across.
That's pretty much the entire size of the Los Angeles area.
So most of the craters on the moon are much, much, much larger than the crater we're going to make and actually, natural craters from asteroid impacts on the moon that are the size of our crater occur about once a month.
So we won't be doing anything to the moon out of the ordinary.
The only unique thing about the LCROSS mission, quite honestly, is that we know exactly where the impact is going to occur and when.
And that's the critical part is we could sit and wait for an impact to hit and reach in and wait and wait and wait because we don't know when that's going to happen.
With LCROSS what we're doing is generating an impact exactly at the right place at the right time.
So ourselves and a plethora of other instruments can observe it all.

>> we're going to know when and where to look.
Jen, we know that the shepherding spacecraft is going to be looking.
Who else is going to be looking?

>> We hope a lot of other people are going to be looking because we -- like we said, we know when and where the impact will occur so we can tell everyone on the earth where to point their scopes to and when so you can observe the impact as well.
We're working with astronomers so they can plan their observations and we're also encouraging amateur astronomers and schools and planetariums to plan an event on the night of the impact and put your telescopes out and watch the impact.
We think the impact probably is going to be observed.
Some are saying to put the shepherding spacecraft so it can be seen.
There's a little bit for everyone.
Hopefully those that make the challenge they'll be in a room that's in a condition to observe the impact, look at the data that comes back and we'll understand it.

>> Absolutely.
Just as a real-time mission and the participation by the -- what we call amateur community is -- well, one, they're hardly amateurs.
Most of them can make incredible observations and we really want to not only encourage that but integrate that into the mission.
What jen is talking about is a very important part of this mission.
Because it's observable, we can really have much, much greater participation in this mission than other missions.
For example, Mars.
A Mars mission is incredible but no one on earth can see the spacecraft go into orbit, see the real results, the real impact immediately real-time.
The images that come back with fantastic but here we're going to hope and encourage that we get the information back from the various groups observing the impact.
That will help us understand what happened and help us in our quest to understand the holes of the moon and help NASA get back to the moon.

>> You mentioned the spacecraft itself right now is being assembled in southern California but part of this spacecraft, parts of it were assembled right here at NASA.
Talk about that.

>> Sure.
In particular, the payload was assembled here at NASA ames.
The payload consists of cameras, quite a bit of hardware and electronics that support those and I think we have an image of myself and jen working in a clean room and that's me in the clean room.
And what you can see is the clean room is a place that is clean.
And the point there is it helps keep the instruments clean, free of dust, free of interference.
What you can see just above the little spots with a number of circles in it, that's the pod.
Payload observation deck.
And inside each of those circles are various cameras and instruments that will make observations of the impact.
Underneath the tarp that is covering it is one of these panels that I described on the spacecraft.
Here at NASA ames working with a variety of vendors, we put together the payload, tested it here and delivered it.
I think there's another picture of jen in the clean room that gives you a little bit better idea of the size of the payload.
The shipping spacecraft will be quite large.
There's six panels that go all the way around the spacecraft.
The spacecraft itself will weigh about 1,000 kilograms when it's fully fueled.
That's fairly large spacecraft.
A lot of work was done to test the engine and jen has been particularly involved in calibrating some of the instruments and I think there's a picture of jen looking particularly cool.
There she is in her U.V. goggles and I'll let jen explain why she has to look so cool working at NASA.

>> The different types of things you get to do when you work at NASA, what we're doing here is in the clean room, we're all suited up so we don't get the spacecraft dirty or the payload dirty so we're testing instruments because of course you want to test the cameras and test the instruments before it gets to the moon.
We test them here on earth before we put them on the spacecraft.
Here we're testing the response.
Basically what we do is shine a bright light bulb and look at it, you know, how bright that bulb is, we look at it with the instruments and then make sure that the instruments are seeing what we think they should be seeing so we can understand.
That's why we have.
U.V. goggles on.
The light bulb we're using was emitting U.V. so we want to protect ourselves.
So we're collecting data here in the clean room and what we're doing now here at NASA is we're analyzing that data we collected with our cameras and we're trying to make sure that the response we get back from the cameras matches what we're seeing with the bright light bulb.
That's just an example of one of the many, many tests we've done with our cameras.
We test them out before it is put on.

>> One of the things we did was when this whole instrument package was completed and you had a sendoff party, getting this thing ready to go and sending delicate instruments like this from up here in northern California down to southern California is actually kind of a major undertaking.
I think we have a video of this and -- there it is.
We talk about what's going on here.

>> This is great footage because it shows our cameras and instruments I was describing.
Here we're cleaning the panel, the payload for final delivery, then wrapped up in a large bag to keep it clean.
The last thing you want to do is work really hard building all of this, testing it as jen described, keeping it clean and then getting it dirty.
We actually did drive it down to California after evaluating a lot of different ways so we had a special crate built for it.
What you see being lifted out, after packing it early one morning, a special truck arrives which is, you guessed it, Fed Ex.
They will take anything anywhere.
This is Fed Ex white glove service.
It's a critical delivery they provide.
We packed it up in the crate, drove it down with a lead car so it was a little convoy that went down to Los Angeles.
It arrived without any problem.
No worries getting over the passes or the hills or anything like that and we drove it in January.
So we were a bit nervous about weather but luckily the weather held out.

>> So now are you folks going back and forth between here and there occasionally?

>> Yes.
There's a few other of our personnel who live down there pretty much.
They come up -- they come up once every other week to feed the cats, but yeah.
They're there helping integrate everything into the spacecraft and then we have a couple of other folks up here who go down there.
Of course, the activity we have some folks going down about a week where they plugged our payload into the spacecraft, made the electrical connection and about a week's time now, they'll flip the switch, turn on the payload and make sure everything is working on the spacecraft itself.

>> Well, that is certainly very exciting.
We've got something even more exciting coming up.
As you mentioned we have a launch coming up this fall.
And NASA will be broadcasting that launch so students out there will be able to watch that and then five days after launch, something interesting is going to happen, too, isn't it?

>> Right.
So once we launch from Florida, about five days after that we'll do a mission, do a lunar swingby and we'll turn on the payload, actually.
Turn on the instruments and look at the moon.
This is a good chance for us to test out the instruments, make sure everything is working OK and also collect some data.
We can also see and calibrate our instruments.
We can cross check our instruments and make sure we're all understanding our data, actually.

>> The instruments actually were -- I think they are cleverly designed so the instruments are looking out while they're attached.
They fly around the moon and we can point our instruments at the moon and make sure all of instruments are working, get our first images of the moon that way.
One thing that jen is very much involved with is working with the observation community on the large ground base telescope and what we've learned is that it's very difficult to point a two meter telescope at the moon.
So the swingby presents an opportunity for them to get much-needed practice in observing the way we're observing so that come impact, they're ready to go.

>> Because we have cameras on board the spacecraft, that means that as we do our fly by of the moon, the students out there will be able to get the views that we're seeing.
We will be broadcasting that.
Then, of course, several months later, what will you folks be doing during the time of impact?

>> Holding my breath.
Well, we have a missions operation center here at ames as well.
Ames is controlling the spacecraft once in flight.
Part of the mission operation center is the science operation center.
The science operation center or soc contains the people who are operating the instruments, looking at the data, confirming the health of the instruments and so forth.
There is a payload scientist in there, I'll be in there looking over her shoulder, making sure everything is operating fine and jen will be there communicating between us and the greater observational campaign, the other 20, 30, 40 people all around the world real-time.
You're seeing what we're seeing?
Move left, look right, that kind of thing.
It's going to be an exciting period.
Now, that final impact, the actual observing time for our shepherding spacecraft is only four minutes after the impact occurs.
We'll turn on 55 minutes before that so we'll have one hour of leadup so it's very exciting four minutes.

>> The cameras on board the shepherding spacecraft, will we see anything from here?
What would we see from those cameras?

>> We've got those five cameras and we are now planning to stream out one of each camera.
Visible cameras will be real-time streamed out.
What we'll see what we turn on the hour out is the moon from about 9,000 kilometers away.
We're moving very quickly toward the moon so we close a lot of distance in that one hour time.
Started out at 9,000 kilometers away from the moon.
We look in our camera.
We'll be getting closer closer and closer and see ourselves targeting in towards the crater.
At impact, we'll see a flash and then we will see a few seconds later, because of the dark crater, it takes a couple of second for the ejected material to come up in the light and we'll see what we refer to as sunrise.
It comes out of the crater and we'll see the twinkling of the mass that expands outward and we'll look at everything from the crater.
Nine hours after that is when we release the shepherding spacecraft.
It has to turn and get the instruments that normally turn this way looking in the right direction of the impact.
When it does that, we actually turn on a couple of our cameras as well so we can watch this impactor, this sensor float away from us.
That's actually the first thing we did.
We'll get before impact, about nine hours ahead, that you can see this floating away from us, from our shepherding spacecraft towards the moon.
It should be a pretty spectacular sight.
We have technical reasons why we're doing it.
It will be kind of cool.

>> So our students will be able to see this event coming across from the cameras aboard the spacecraft, with their telescopes they can watch the impact here on earth.
How long do you think it will be before we understand what we found?

>> Well, if we get our work done, as jen described we're working hard on building the tools to understand the data right now so they're all ready to go.
If that goes according to plan as it is now, we should know quite quickly whether or not we see water in there.
We expect within three months after the impact to have a definitive answer one way or the other.
Maybe sooner than that but that's the time frame we're committed to.

>> You folks will be very, very busy.

>> Extremely busy.
The science team is four, five, six people.
These people will be turning the crank on that data and analyzing the images, really looking for the water is one of the principle goals but there's so much more science to it.
We're going to a place we've never been before.
We've been to the moon but never been to the hole of the moon.
These craters are some of the coldest things in the entire solar system.
They could be 230 degrees below zero centigrade.
Very cold.
They could contain material that is 3 billion years old.
We're really going to be discovering, exploring something and I think we're going to have to be ready for the unanticipated, the unexpected.
So that three months is going to be a time of exploration unto itself.

>> You folks are going to be very busy but we're also going to have some very busy students out here.
We've got a number of students who are excited to participate in this mission through our quest challenge here.
Part of the focus of this challenge is taking a look at the whole concept of experimental stimulation.
What is experimental stimulation?
Why do we do this?

>> Well, we're trying to answer questions we don't know the answers to.
We're trying to understand what's going on here.
We do this type of work for not only the information for Mars as well, we haven't sent people to Mars yet.
We want to see what's there so we do things like that on earth, try to understand what's going on with other planets.
That's part of the idea behind the challenge and what we're doing on the LCROSS project every day.
We're sending out experiments and in particular, this experiment to try to determine the impact.
What would the impact be like?
How much material will be ejected on the impact?
How does it depend on the mass that's impacted?
All of those questions you can attempt to start answering by doing an experiment on a different scale.
What's going on when we do that process?

>> I should add what jen described was critical to the start of LCROSS.
Very initially when we were proposing the idea, we did those kind of experiments on a very small scale to just guess what you might be able to do.
Then when people asked, well, this is interesting, tell me more.
We did more experiments and they were critical to understanding in particular the experiment we're proposing here today was critical to build the mission design for LCROSS.
The angle at which we impact this rocket is very important to understanding how much material gets thrown up into sunlight.
And so those experiments were some of the very first experiments we did.

>> So when we're asking these students to come up with ways to stimulate the LCROSS impact, we're having them do something that is potentially the same thing that you folks have been doing and are continuing to do here today.

>> Absolutely.
And I've got to say that those three months following impact, we'll be revisiting all of these models to help us understand and interpret what we see.
Most -- some may be dealing with the impact project.
The same kind of experimentation was done to understand that after the fact, talk to other experimentalists, what it took was a broad community of experiments to come together to really interpret what we see and then follow-on experiments and I anticipate we'll be looking at what we did, looking at what the students did and maybe conducting more experiments to really understand what it is that occurred during LCROSS impact.

>> Sounds like great training for the students, too, for being involved in future missions.

>> Absolutely.

>> Absolutely.

>> Now, we talked about da*ib a little bit about some of the factors that go into characterizing the impact, figuring out how much stuff we're going to throw out of the surface of the moon.
We mentioned what was mass and velocity and I guess both of those things very quickly are understandable.
A big rock and throw it down, you get a much bigger splash than if you throw a small rock around.
Throw something fast, you'll get a bigger splash than if you just let it drop.
You also mentioned something about angle of impact.
What is the angle of impact and why is that important?
Why do you think it might be important?

>> Sure.
Use this model again.
The angle of impact describes whether or not the impact will come straight down or come in at an angle, sideways.
This spacecraft, the European spacecraft impacted a year and a half ago.
This table is the lunar surface.
It would have come in at this angle.
It was almost parallel to the table.
It probably skipped and bounced.
What we need to understand is that throwing ejectile, how big is the splash when you throw something at a low angle as opposed to if you come in with something very steep.
Is there a perfect angle in between here and here in terms of the direct of impact that results in more or less or just the right amount of material that's thrown out?
One of the difficult questions we haven't answered.
You're right, Brian, it's much more intuitive or understandable, the more mass, the bigger splash.
But that angle, how it affects the kind of hole, how much will get thrown out.

>> It sounds like an interesting question to have our students help us discover.

>> Yes.

>> Very good.
Now, NASA has ways that they are doing the simulation right now.
But we're not going to tell you that.
Right now what we want to do is find your ideas.
Varying this angle and measuring the kind of material, the amount of material that you get coming out of the impact, tell us hopefully which kind of angle would be best coming in.
That's pretty exciting.
Now, clearly there are some safety issues.
We're talking about having that impact.
Safety plays a big role in the experimental stimulation.
Can you talk about safety and the role that plays here?

>> Safety first.
Don't do anything if it's not safe.
You take all of the safety precautions that are necessary.
If there's a great big experiment that you want to do, if it's not safe, you don't do it.
We deal with that every single day at NASA.
Safety is above everything else.

>> The NASA motto is safety first.
We take that incredibly seriously.
We keep ourselves and our equipment safe.

>> That, again, will be something that we'll probably want to emphasize to the teachers out there who are participating in this and again, that's something that we want to make sure you have a good learning experience in the classroom and a safe learning experience.
One of the things we're going to be doing in the course of this is give you a chance to come up with your ideas and then a little bit later on, we will have a web chat where you'll be able to interact with some of our experts and maybe get some questions answers and refine your ideas and then later on, you'll submit your design to us and we will have a final web cast like this where we will have our expert scientists going over your design and see what type of design you came up with, what kind of results you came up with from your experiments and then what we will do is compare that with the kinds of tools that they are using, the results that they're coming up with.
That will be a very, very interesting comparison to make.

>> One last point regarding safety and maybe a suggestion going forward in their experimental design is like you described, Brian, the velocity and the mass are a little more intuitive, better understood.
And I think you'll get good results, independent of how fast you throw whatever it is you're throwing.
So I don't think you need to work hard to have something go really fast.
More important is probably, like you mentioned, having an experiment that has a constant speed.

>> So even though the LCROSS impactor is coming in as twice the speed of a bullet, it's probably not a good idea to have your impact in the classroom moving at twice the speed of a bullet.

>> That's what I'm getting at, yeah.
Probably not a good idea.

>> Actually, you're talking to a question that we have in the chat room.
It says, are our observations going to be taken seriously?

>> Absolutely.
I was maybe not direct enough with my pitch a bit ago.
We want to understand this.
It is non-intuitive and having a lot of information and data on this is going to be very, very helpful.
As I mentioned before, with the deep impact, the one that crashed into the comet a couple of years back, a lot of professionals did a lot of impact models and none of them were exactly right.
It took combinations of different models to come up with results.
And that's what was great about it.
We really learned something about that comet that we never really anticipated but it took a broad combination of ideas and results to make sense of it.
Once we impact, we've done impact experiments as I mentioned to prepare ourselves, to design our mission.
But once we impacted them to get our data, we're going to be looking at something that we probably won't understand 100% just how it works.
So looking at your results, there will probably be clues in there to exactly what happened on the moon when we impacted it.
So absolutely.
I fully intend it to be taken seriously and hopefully it will contribute greatly.

>> And that's just part of the scientific process.
Different experimental setups and look at all of the results from all of those different experiments.
So each school can look at the results of the other groups.
That's exactly what we'll be doing on the LCROSS, too, looking at all of the different data sets.

>> I think we're hoping to see that there are a variety -- there's a real variety.
People are taking different approaches to doing this because each approach may show us the different view how this works.
It also probably ties into something we should process here and that's limitations on the experimental simulation.
Probably no one is going to come up with a perfect moon-like environment to test in.
Let's talk about that a little bit.
How important is it to understand the limitations and the differences?

>> It's really important because part of doing the experiment is realizing that you are not replicating some type of impact perfectly.
There are parameters that will be different and are different.
You can isolate those and try to understand them but look at different experimental setups and different processes to try to understand, OK.
What are our contributions that aren't the same as the actual impact event?
Looking at different experiments, you can sort of understand where your processes are.

>> That's an important aspect to it.
That's why seeing a lot of different approaches is very valuable.
Getting back to deep impact, that was very useful.
There were multiple layers of different materials of different strengths.
We really didn't know how strong the material of the comet was we were impacting and once we saw the results and checked the velocity distribution of material, they -- the various groups modeling it had to go back and say, well, what part looked right?
What didn't?
What was our setup?
We only had a single layer.
What if we put two layers in there of different densities?
That's looking like what we saw.
That's how LCROSS will work.
We've never been to a dark crater.
Is it like -- is the lunar dirt here the same as at the Apollo site?
I don't know.
We're going to find out.
Is it stronger?
Is it for consolidated?
We're going to learn this by understanding how the ejector came out.
It's one thing to look for water ice but understand how much comes out, how is it thrown out at different angles, that will tell us a lot about what it is we actually hit.
That discovery is what jen just described.

>> That's an interesting point.
We are going somewhere we really have never been before.
We're looking at visions that may be -- we certainly don't have a great understanding of at this point.
I've heard the phrase used before amongst the group of no bad data.
Basically we don't know what we're finding here but what means a success?
Do we have to find water for this to be a success?
What's the criteria?

>> On the bad data comment, I don't know.
Some of it is just in operating the instruments, getting ready, the testing and testing and testing we've done, there's no bad data there.

>> You learn something.

>> You learn something.
A lot of times it's because the setup was slightly different on Tuesday compared to Wednesday and you're like, hmmm.
Why are we seeing this little difference?
You go back, understand the difference and setup and learn something about how the instruments operated.
So that said, absolutely there's no such thing as bad data.
We saved every bit of data from cameras and all I hear from scientists is boy, I wish we had taken more data.
There's never enough.
You always want more.
The science is not defined by a hypothesis or a proof and then confirmation of that proof, absolute confirmation.
You build a test hypothesis.
Is there water on the moon or not?
We're going to test it by making that impact.
If we get a zero result, no result, that would be a scientific process.
It just adds to our knowledge of these craters within our experiment.
We only excavate a certain amount of material but we're testing the hypothesis of the, quote, possible form of this hydrogen on the moon.
So if LCROSS doesn't see water, what it tells us is, well, whatever that hydrogen is, it's not in the form of water at these two locations at this scale.
That immediately tells us something about the process.
The way this water got there in the first place has to depend on certain things that work at certain length scales and time scales and so on and so forth.
It's giving us more information to build our ideas about how the vapor evolved.
It helps the exploration part of NASA in determining, well, how far do I have to drive then to find the water?
If I'm a Rover and I'm trying to dig up water ice and these two locations made holes the size of a tennis court, didn't see water, I have to be a little bit smarter how I search and maybe I'll decide it's too expensive to do it that way then or I'll decide, well, I need this kind of architecture to do that.
So regardless of the outcome, it steers the discovery process, the scientific process forward.

>> So it sounds like whatever we find is going to be interesting and potentially valuable.

>> It will be interesting and absolutely valuable.
Not even potentially.

>> Very good.
And again, this mission provides an opportunity for you, the students, to actually be participants to work with us to help observe, to help understand.
The contest we're talking about a little bit earlier, no bad data.
There's always a need for more data.
With your experiments, with your designs, you're going to help us.
Thank you very much for your participation in this very exciting mission.

>> OK.
We have to be pretty firm on subject, but as it is, we're not going to be able to handle a lot of them but I do want to reemphasize something that you addressed earlier but we're getting several questions.
What if the moon hurdles into the earth because of being hit by LCROSS?

>> Do you want to take that?

>> We get this question a lot and it's a good question.
And I appreciate a concern that anyone would have when you conduct an experiment like this.
As I described earlier, the picture behind us is a picture of the moon.
You can see all of the holes that natural impacts have made on the moon and the one right over his head right here, it's hard to point on the scene right here, is shoemaker crater.
It's 35 kilometers from rim to rim.
That's about L.A. would be about the size of my hand.
Los Angeles would be about the size of my hand.
It was made by an object that was probably three to four kilometers across.
Our impactor is about 10 meters in length and two meters long.
It will make an impact that you won't even be able to see on this picture here it's so small.
The kind of natural impact that would create the same size crater that we're creating would come from a meteorite the size of a tennis ball, about my fist because natural meteorites hit so much faster than what we're hitting and hit somewhere around a month on so.
The moon is always getting hit and will continue to get hit by small impactors, impactors the size of LCROSS.
It really does nothing to affect the orbit or the phasing or the sims of the moon.
The material we throw up settles back to the moon in a matter of literally minutes and doesn't last long at all.
And just like the natural impact, it's the same process that occurs.
There really isn't any threat at all to the moon or to ourselves from this impact.

>> This is a great opportunity to do just what scientists will do, what the scientists here do.
And that is to do the math, find out for yourself.
Don't just take our word for it.
We talked about the velocity we're going to be coming in at.
We talked about the mass we're going to be hitting the moon with.
For those of you taking physics courses, remember kinetic energy.
So you can calculate how much energy we're going to hit the moon with.
I would also encourage you to look up and to find out how massive is the moon.
We're coming in with something that's massive like an S.U.V.
That sounds like a lot.
Now compare that to what the mass of the moon really is.
And you can find out for yourself how big of a push are we going to give to the moon.

>> Excellent experiment to do themselves.

>> Okay.
We have a lot of questions that sort of dovetail but having to do with why is it so important to find water on the moon?
How can there be water on the moon when there's no oxygen?
The Chapel Hill algebra students ask.
Another asks why don't you create water by bringing oxygen to the moon?
It sound like --

>> I'll let jen take why the water is so important question.

>> Why water is so important is because NASA's next step is to go to the moon.
First we have to do sperms with LCROSS and the Rover and using that information, build up and send people.
We're sending people back to the moon.
We want to go for longer periods of time so we want to learn how to settle and stay there.
To do that, it would be beneficial potentially to use materials that are already on the moon, live off the land, so to speak.
So if there's water that's there on the moon, potentially we can tap into the water and use it instead of having some water taken to the moon which can be difficult and expensive.
If the water is there, why not use it?
If it's there, break it apart, hydrogen, oxygen, use it for rocket fuel, building materials, all sorts of things.
It's a really important question for when we send people back to the moon.
And we need to find out if it's there, why is it?
That might dictate where we send people.
There's a lot of questions for planning when we send people back to the moon and also it's an important scientific question.
Is there water on the moon?
How long has it been there?
How does it stay there?
Remember, we're looking at these very, very cold craters.
So if water was delivered by a comet, by a meteor impact and you think water is delivered to the earth as well, it might stick around.
It's not going to evaporate.
That's what we're going to test.
It's important for our future exploration to the moon and also important for science to understand where the water came from if it's there.

>> If I could expand on that, just to follow water here, jen mentioned how expensive it is to carry something into space.
Right now the going right is about $10,000, $12,000 a pound to lift something into orbit.
To go to the moon you have to expend a little more fuel.
It's about $15,000 a pound for 20 fluid ounces.
This would cost $20,000 to go to the moon or so.
That's for one bottle of water.
If you want to go there for an extended stay, it's something you want to consider, being able to live off the land.
In particular if we used the moon as a learning step to going beyond the moon, to Mars perhaps, what we can learn on the moon about utilizing resources is very valuable when you start going to places that are further and further away.

>> OK.
We have several questions and I'm going to have to cut it short because I'm seeing rear really running overtime here but several people have asked about can you sleep in the spacecraft, does the LCROSS moon on its own or does it have a remote so maybe we need to demystify a little of how this is going to be controlled.

>> There are thrusters on the spacecraft and you can't see them on my model because it's too small.
They're little thrusters about the size of the water bottle and they expel fuel out and that fuel, again, basic to physics principle is push one way and you go the other way, right?
That same thing is happening on the spacecraft.
Excel fuel out one direction and the rocket goes the other.
The computer on the spacecraft actual where we tell from the ground where we want to go.
We want to go that way.
The computer on the spacecraft, by looking at stars and looking at where the sun is, knows where everything else is and says, OK.
If you go that way, I'm going to fire these thrusters, the rocket jets and propel myself in that direction.
So that's how the spacecraft itself operates.

>> And just to be clear, there are no people on the LCROSS spacecraft on this particular mission.
So this spacecraft that we're talking to you about is completely robotic and all of the people are on the groundworking computers and controlling the spacecraft from there.
Then the people will be sent to the moon later.
We do the first step of sending the robotic is.

>> That's a very important point.
On this one moon rocket that's going to launch this coming fall, there will be two robotic spacecraft.
The Reconnaissance orbitor and LCROSS.
These are lunar crater observation sensing satellites.
These are the spacecraft that are going to essentially lead the way to the moon before we start sending people.
They're going to study the environment, give us a better understanding of the surface of the moon before we send people, perhaps you, to live on the moon.

>> Great.
Just two more.
One is how long does it take to get to the moon?

>> For us, in this particular low energy transfer, five days.
Four or five days.

>> OK.
And then a final one that I found very interesting.
Could it be possible you'll find something else on the moon?

>> Absolutely.
That something else I could speculate but again, we're going -- this is really a mission of exploration.
We are going some place where we've never been before.
We know there's hydrogen in these dark regions but the question is how could it be?
Jen explained it well.
It's so cold, minus 200, 220 degrees below zero centigrade that once water gets there, it sticks.
It traps there for a long time.
Four billion, three billion years.
Other things could get stuck there, too, like methane, other gases, hyrdro

 FirstGov  NASA

Editor: Linda Conrad
NASA Official: Liza Coe
Last Updated: October 2008