>> Curtis Wong: I want to thank everybody for coming this morning. It was a little bit short
notice, but we really appreciate your being here. I'm excited to introduce Megan Watzke who's
with the Chandra X-ray Observatory. She's the communications officer for them. She's going to
talk about some of the books that she's been working on. The most recent one we have copies
of up here. It's called Light. That's actually in Costco. It shows you how many copies are out
there. And then another really excellent one is called Coloring the Universe. It's about the
work at the Chandra x-ray Observatory, the work that they do et cetera. And there's another
one, which is an earlier book called Your Ticket to the Universe that is floating around here. So
let's all give Megan a warm welcome and take it away Megan. [applause].
>> Megan Watzke: Thank you, Curtis, and thanks to all of you guys for taking some time out of
your busy day to come and listen to what I have to say. As Curtis mentioned, I work for the
NASA Chandra X-ray Observatory and I don't know if you guys know about it or not, but most
people have heard of Hubble and that is obviously an orbiting telescopes it looks that looks at
visible light. Chandra is a sister mission to Hubble and instead it looks at x-ray light from space.
It was launched in 1999 aboard the space shuttle Columbia and it has been operating for 16
years. What I do in my day job is I am press officer, which means that I translate the results
from the telescope that scientists have, the discoveries, and turn them into press releases,
press briefings, web stories, whatever. And a big part of telling the story of what has been
discovered involves images. That leads you down a bit of a path in and of itself. Most people
when they see something from Hubble they say okay. If I had a big enough telescope I would
see that with my eyes, which is actually not really true, but we'll get to that. But if you start
talking about x-rays people start saying why do you have a telescope that looks at x-rays? So
you inevitably have to talk about that there are different kinds of light. You go through the
electromagnetic spectrum and all of this, so you have to start at the beginning which is that
there is more than the light that we can see with our eyes. We take this for granted if you're in
a technical field or involved with physics in any way, but most people don't know that. They
just think of light has been illumination. That was sort of one of the reasons that I ended up
doing, we and my co-author Kim Arcand and I end up doing the light book which is somewhere
in the room, to basically just expose people to the different kinds of light that are out there and
how even if you don't know if you use different kinds of light every day, and they affect us in
different ways. The book I'm really going to focus on today, however, is Coloring the Universe.
The story behind that book is our good friend Travis Rector is an astronomer in University of
Alaska. Until recently, I think he was the only astronomer in the whole state of Alaska. I think
he knows a friend or a graduate student. And he is done a lot of work over the years taking
images from places like Kitt Peak and Gemini and other mainly ground-based telescopes and
turning them into pretty pictures. That is something that some astronomers don't do. They
just get their data. They analyze it and they go on their merry way. Travis over the years has
found joy and personal satisfaction and purpose in turning the data he takes and turning them
into beautiful images that the public can understand and use. You see these images
everywhere. You see that on posters. You see them on billboards. I don't know if I should say
this. You see them on the back of Apples, on the screen savers. Space images are very, very
popular. Their popularity I think is a testament to the fact that people are interested in space,
but there is a downside in our digital world. That means people often question is what they are
seeing real. We live in, Star Wars will come out next week and in case you haven't heard
there's a lot of digital effects out there in movies and whatever, and there's a lot of
Photoshopping. We now live in an age where Photoshop is a verb and it is often a negative
one. People have approached Travis and have approached Kim and myself over the years and
said that's really pretty, but you just made it up, or is that really how it looks, or whatever. The
Coloring the Universe book is really aimed at explaining exactly how astronomers get these
pictures, where the colors come from and also all the steps that we take to get there. I will give
you a little bit of an overview about what's in the book and then give you some resources at the
end if you want to hear more. Just to go back to the electromagnetic spectrum, Chandra is the
one on the bottom that looks at x-rays. If you look at the bottom you'll see that it's a little bit
backwards. The left side is gamma rays and the right side is radio waves. You can see that
astronomers have an amazing toolkit at their disposal these days. Basically, and this is just a
sample, they have telescopes that look at almost every single part of the electromagnetic
spectrum. And they really need this, not just for fun. They need this to fit in all the pieces of
the puzzle that they have in order to give the complete picture of the universe. With a nice
corollary to that is that while they are answering the scientific questions they often can get
great data to make spectacular images. And these multi-wavelength images, I would argue, are
some of the most profound ones we have out there. In fact, sometimes the single wavelength
images almost look to me kind of naked. I'll show you some examples in just a minute. But we
use this analogy for the public that if you just had your visible light, if you just had the light that
you can see with your eyes and you had to go -- say you had an alien friend that comes to the
United States and I'm from Boston and so you take him to Fenway. But the alien can only see
down the third base line. So that's your vision if you just had visible light. So you're trying to
explain the game to your alien friend. He's got to figure out the rules, all that stuff. It's next to
impossible. Even if you had Hubble you would only be seeing down the third base line if you
just looked at the universe visible light. Of course, I actually don't think that's Fenway.
Anyhow, you need the whole spectrum from radio to gamma rays and everything in between in
order to -- I don't know where it's from -- to really get a full picture of the universe. Also it's
Cleveland. Okay. Anyhow, not my photo. Anyhow, so what do astronomers do and why do
they do it? There's a little bit of misconception as to what telescopes do. Let me start with
what that involves. There are three goals of a telescope in very rough, very basic forms. The
first is to magnify, and this is what most people think of when they think of telescopes. They
think that they kind of work like binoculars. You go. You look out. You see something that's
really, really tiny and it makes a bigger. That's to some degree true. That's what a telescope
can do, but that's not all it does. More importantly it collects light and that means that you can
take, you can get more photons of very faint objects that are very far away. That's very
important because our eyes cannot do that the matter how much we wish they could. And the
third thing is that we'll get to more is that it expands what we can see beyond the range of our
eyes, what our eyes cannot see. If the electromagnetic spectrum were a keyboard, a piano
keyboard, the amount that we can see would maybe be two or three keys around middle C. It's
really a very small portion of all of the light without there. So what astronomers do is they
build telescopes to expand that vision both for magnification, faintness and also for getting
outside of those few keys on the keyboard. For example, just to give a number here, this is the
amount of collecting space we have in the human eye. It's about a quarter of an inch across.
You can only collect light through the pupil. It's not very big. Very good for getting around the
earth and interacting, but not so good when you are talking about getting very distant objects
and seeing what's going on. By comparison, this is the eight meter telescope that is now in
Gemini North. We were just talking a second ago before people came in. There are plans in
the works to make a 30 meter telescope. It would probably be a single piece of glass like this,
but it would be, 30 meters is really big. The biggest amateur telescope would probably be two
feet across. This is 27 feet across, so you're talking about making a surface area much, much
bigger and it can collect way more light. And the other thing that telescopes can do that the
human eye can't is that the human eye takes an image about 30 times a second, not a very long
exposure time. For some of the most famous images that we've ever had, the couple extreme
deep field, I believe, is the equivalent of 50 days worth of exposure time. Granted you're
stitching those together, but you can add those because you can. That's the way it works.
These are some of the things that telescopes do that we cannot. What does that all mean and
let me just show you a couple of examples before we get back to how we make the images.
Going back to the need for different telescopes, this is the famous supernova, Cassiopeia and
this is a star that exploded about for hundred years ago in the night sky. This is an image from
Hubble. It's nice. You can see some of the filamentary structure. And this stuff that we're
seeing here is going about 10,000 degrees, which again, pretty hot and that's nice. But in order
to sort of really see it, if you add in x-ray light from Chandra you see a much, much different
picture. The difference between these and we can add these together and these are actually
two separate images and we'll get to the combined image in a little bit. And what do we do in
order to get these images? The images that come down from telescopes like Chandra and
Hubble, from space telescopes they come to us as ones and zeros. For example, a telescope
like Chandra we take the ones and zeros and we know where each photon has landed on the
CCD detector. There's an event table and you can basically print out where, you can name the
photons if you wanted and sometimes they do. And they translate those event tables into
black-and-white images. That's where Photoshop comes in. In Photoshop what people that
make images from an astronomical data do is they make layers. I'm sure if you guys have used
Photoshop you are familiar with this. These layers are then colored and this is where I think a
lot of the confusion arises is that people think that the colors from astronomical images are
somehow, either they're randomly assigned or they are either a real color image or a false color
image. And I'll get to the topic of false color also. It's a very unfortunate term, the term false
color, because it somehow implies that things are being faked. Again, we're back to this issue
of Photoshop and it somehow gives the public at least the perception that scientists are making
it up and taking out their box of crayons and just coloring things as they want. This part will be
blue and this part will be red. That's actually not how we do it. We instead, translate what is
this into as I said these event tables that are then made into black-and-white images. Just so
you understand how something like Chandra works, Chandra is in space like Hubble. And
something goes off in the universe and Chandra observed at and then it relays it's data every
eight hours or so down from the satellite through what's called the deep space network and
then those data are sent to our headquarters at the Smithsonian Astrophysical Observatory in
Cambridge Massachusetts and eventually given to the scientists who proposed that
observation. It arrives to the scientists obviously electronically and there is no image at that
point. Scientists then take the data and they probably do something like this, which is useful
for the scientific community. That's a real x-ray image on the side, but it really isn't very useful
for communicating to the public what is being seen, what the context is and so on and so forth.
So we need to find a way to translate the raw black-and-white data into something that's
meaningful and color helps give it meaning. But if you want an example, as I showed quickly
before, and that's this image which is the so-called pillars of creation. This particular version I'll
show you an updated version later, was taken in 1995 by Hubble and it's perhaps one of the
most famous astronomical images ever taken. The steps you see are just a byproduct of the
camera on Hubble that took it. When it came out it really captured the imagination of a lot of
people. It looks unworldly. It looks like it's black-and-white, but in color it looks even better.
And the colors come from more or less in this particular case red green and blue layers that
have been stacked together. I'm going to not remember exactly which layer is which, but these
are not, the colors are layers of specific elements that are being emitted. One I think is oxygen,
one is sulfur and I don't remember what the third one is off the top of my head. This leads me
to sort of talk about the different ways that you can take astronomical images. Some
astronomical images are called broad band images which basically means that a telescope looks
at a chunk of electromagnetic radiation, all the visible light, let's say. And then in that broad
band you can choose to cut it up in different ways. You can choose to cut it up low, medium
and high. You can do this for x-rays. You can do it for radio waves. You can do it however you
want. This used to be the standard of how people would do astronomical imaging. They would
low, medium high to correspond to how the eye works. That's one way to do it and it also
mirrored how photography was developed and how astronomy developed photography over
the twentieth century. As we move into the twentieth and twenty-first century, we now have
way more colors and options at our disposal. The red green and blue palette does work
sometimes and it sometimes creates very spectacular imagery. However it's not something
that astronomers adhere to. You don't have to stick to that color scheme. It does make sense
on a physical, physically to some degree that the low represents lowest energy, green the
medium and blue the highest. But the point is that astronomers sometimes adhere to that and
sometimes not and it's not random, but there is an aesthetic component that goes into the
decision and it really is to show both what is the scientific point of the image and also what is
the most beautiful image and striking image you can take, because if you are making images
that are distracting and not appropriate for not attractive to people, then they are not going to
consume the information that you are hoping to get out of that image. For example, here is
another example of an image that is not red, green and blue at all. This is an x-ray image and
it's an x-ray image of a supernova remnant called G 292 and some other stuff at the end which I
forget. The important part of this image was to show the elements that a scientist can see with
this expanding debris field from this exploded star. So as you guys probably know, supernovas
seed the universe with important elements like oxygen and silicon and the calcium in your
bones and the iron in your blood and understanding exactly how they do this is very important
to astronomers and also for us since we are a byproduct of some long-ago supernova. So this
particular image was colored using the color scheme down at the bottom. Oxygen is yellow and
orange. Neon is in red, magnesium green, silicon and sulfur in blue. And it really depends on
the data set you have and showing what is important and working with the scientists who took
the data to tell the story visually of what they're trying to communicate and then finding that
balance between making it aesthetically pleasing and also scientifically accurate is something
that we do. You always basically have to look a little bit deeper at the images to really find out
what's going on. But I'll pause here for a moment to say that when the things that we really
pride ourselves on is that everything is transparent as far as what we do. Again, there is this
potential mistrust of scientists and whatnot that they are somehow manipulating the data in a
sort of negative way, doing things that are not real. It's made up. You know, we've all heard
there are conspiracy theories for everything from the moon landings to whatever. We take it
very seriously, and me working for NASA that we are very open and honest about what is done
to every piece of data and that it is reproducible and we actually have a lot of tools that we
make available to the public so that you can go take the data and do the same thing, and that
we don't just randomly color features a certain color. These are the layers of data. The layer of
oxygen is what it is and we don't cut it out if it's not convenient. It's very important that
whatever decision is made about everything from cropping to color to whatever, that those are
disclosed, because otherwise, we leave room for criticism and disbelief. We know that
scientists don't need any more disbelievers out there right now. We know that we are here to
sort of promote science not to give someone a reason to attack it. That's one of the things that
at my day job we are very adamant about and one of the reasons why we did the book is that
we want people to understand if they are curious, what actually goes into making these images
so that there is no potential for just trust. Sometimes we use images that involve more than
three colors as we did in the last ones. This line involves seven. This image is from Hubble of
the galaxy NGC 1512. Again, if by adding all of these separate pieces up, combining them into
one image, that's what you see in the middle. But we also make the separate layers available
too so that as a layperson or if you are just interested or whatever, you can see what went into
the final product. A lot of people won't go and find the final product, but we make that
available in case they want to, so it's not a mystery, like you just made that up. Going on
further to talk about different kinds of objects that give off different kinds of light, perhaps, the
nearest and dearest to us that we can all relate to is our sun. These are images from The Solar
Dynamics Observatory and I can't remember how many different wavelengths are represented
here, but a handful. Our sun gives off almost every kind of like from radio waves to gamma rays
and we need to study all of them. These kinds of images are used to sort of help show people
the different features of the sun, what happens in different wavelengths, what happens at
different temperatures and they're all important. I think, again, the most important thing to do
with something like this is to explain to the public what we're doing, why the colors are used or
which ones are used, because the thing is color adds information. If we were to look at a
weather map like we're getting a big storm coming through here in Seattle. You look at a
Doppler radar screen and if it's in black-and-white you don't know where the heaviest rain is.
You get a Doppler radar screen with red as the most intense and green means the least, you
can understand more. You get more information. It's the same thing in astronomy. It's the
same thing in scientific images. It's just that you have to explain it. You can't just assume that
people without that knowledge base are going to automatically understand without that
explanation and that, you know, jargon free example. So going elsewhere in the solar system
we take pictures of other planets too. Color is important. We call Mars the red planet for good
reason. This was a picture taken from the Curiosity rover back in 2012. We have to calibrate,
what the planetary guys do is that they will calibrate the sky so that it matches up with a sky
that we would recognize to therefore calibrate the red. So you can land on Mars and take
pictures but if it's not calibrated right it just looks odd. This is a merged picture of the two
images above. There are color corrections done all of the time especially in science and, again,
for good reason. Sometimes we take images from different kinds of telescopes. So far I think
I've just shown you images of different colors found within one wavelength, x-rays or visible
light. There's a reason to combine them together. One of the most famous objects is the crab
nebula exploded, I can't remember the date, about 1000 years ago. What's that?
>>: 1054.
>> Megan Watzke: There you go. Thank you. That famous objects was observed by a Chinese
astronomer around the world at the time and since then it's probably one of the most observed
objects in astronomy. This will show you what it looks like if you look at it in different kinds of
light. This is the x-ray image from Chandra. You can see it looks like a little vortex or whatever.
This is some infrared data also, and if you add in Hubble optical, that's that. You can see the
outer shell that it's moving into. And you combine them all together and it really provides
context that I think otherwise is just lost. You need to have these pictures. Again, you notice
the color scheme, blue, red and purple. It doesn't really follow the chromatic, which is the red,
green and blue color scheme. These decisions are made, again, by working with the scientists
and working with the professionals about what is going to make the best image and we, again,
try to fully disclose every step along the way so that when this image goes out there it's not just
thrown out there into the public. It actually has some context. And we now have in the
astronomical community we have done a lot of work with metadata, so that even if these
things are randomly found on the internet, some of the important information about color and
other things are embedded within the data so that we're trying to make it as uniform as
possible as sort of a proof of purchase. If you find this image you can trace it back to where it
really came from and that information is not lost. Similarly, we can look at things like galaxies.
This is the Pinwheel Galaxy, otherwise known as M101. This takes for different telescopes, xrays from Chandra. It takes, I think this is Galex, which is ultraviolet. Then we have Spitzer and
this is Hubble, I believe. Put them all together and you end up with that. Again, some of these
images are, look kind of funny to me when they don't have the different wavelengths stuck
together. And each element gives you different pieces of information. X-rays will tell you
where exploded stars are, where x-ray binaries are. Infrared, for example, will tell you where
the dust is in the galaxy. The optical light will tell you where the older stars are and ultraviolet
will tell you where the younger stars are, so you put all these pieces together to get a complete
picture. Another example is the Cat's Eye Nebula which is a planetary nebula which actually has
nothing to do with a planet. It's a really bad name for this category. It's really just the end life
of a star like our Sun. Our Sun one day will go through this phase one it runs out of fuel, sheds
its outer layers and so we can look at it with x-rays and you can see the middle of it. It's just
sort of the harder cocoon that's right around the star. And then you add in the optical layers
and then you can see sort of what has happened in the context of the shed layers with the
ongoing heated material in the middle. So just to shift gears a little bit, I want to mention it's
not all random. We don't do this without thought or without understanding some of the
consequences. We actually studied some of these choices. My coworker, Kim Arcand led a
group called Aesthetics in Astronomy. It's a research organization project that combined
astrophysicists with psychologists in studying how people react to color and how they react to
color in scientific imagery, in particular, astronomical imagery. As opposed to only going with
our gut feeling like I think this works for the public, there's really now some research behind
what is useful and what is not, what is confusing and what is not, and part of it has to do with
understanding visual grammar. We understand that those mountains in the background are
bluer and that means they are farther away. So there are ways to select color in astronomical
imagery that will help guide the I in a way that makes us as humans interpret the data in a way
that will perhaps convey depth, convey distance, the distance behind that. You know, this is
closer than that. Also the issue of heat. We talk about that if you are familiar with physics you
know the hottest things are blue. But if you talk to the public, they'll say that red is hot, so
what do you do in a situation? If you are trying to convey something is hot, do you make it
blue, which is scientifically correct, or do you make it red? And these are choices that you have.
You're not distorting anything. You're simply making a color choice. There is one example that
Kim's group tested. This is NGC4696. It's an elliptical galaxy in the Centaurus cluster about 150
million light-years from Earth. We originally did this. This was the original one. This was the
original one, and so blue is the hotter stuff. That's where you want it to be. But when we
tested it people thought that the redder stuff was hotter. So you can flip them and it seems like
an arbitrary choice, but it's actually important because if your point is to tell people what's hot
in the image and what's cool, you have to understand your audience. By the way, the
aesthetics of the astronomy project includes astrophysicists that we test and it's often
diametrically opposed to what the public thinks. So it depends on what your audience is. If
you're talking to your scientific colleagues, you give an image where blue is hot. But if you
really want the public to at their first glance when they are flipping through their news or
looking at the astronomy picture of the day, if you want them to understand or think about
something being hot, you might pick red. Is there a right way to do it? Not really. You can
argue both ways, but I think the most important thing is that you give it thought and you
disclose what you've done. Label what colors are what and be very upfront about it. And I
think the other thing that our research has shown is that the public will voraciously consume
any of this stuff. You really have to have clear information that goes with it. Otherwise, it's
meaningless at the end. We found that almost what the image looked like didn't matter. It did
matter, of course, but it was also equally important to have well-written, clear captions to go
with it. Otherwise, you could have the most beautiful image in the world and people might
look at it and say that's cool and walk on. You could have something that is kind of funky
looking and you explain it well enough and you are going to hook them. My job is to hook
people on science and to get them engaged. I think that images are one of the strongest things
we have going for us in science, especially in a field like astronomy. I just wanted to shift gears
and talk about something that was kind of a fun topic at the end of the Coloring the Universe
book that is our final chapter because it's one of these things that always makes the rounds of
the internet or whatever and often involves astronomy. It's the phenomenon of parediolia.
Ignore the first d. It's the phenomenon of seeing familiar things, especially faces in noise or
data or whatever. If you always hear about it, you know, like seeing Jesus Christ in toast or the
Virgin Mary on a windowsill, but it happens all the time in astronomy. That was kind of a funny
thing. And so we kind of played with it a little bit at the end of the book and one of the most
famous cases is the face on Mars. The corner image is the image from Viking in 1976 and it
looks kind of like a face. It freaked people out, totally. This was pre-internet obviously and so
like imagine what would happen now. This is an updated version from the Mars
reconnaissance orbiter that in 2012. There is no face. There is no person. I think there were
some bad movies actually made because of the lower right image. I blame Hollywood. But it's
not just Mars. This is an image that I was involved with and put out and it was nicknamed the
Hand of God and that was not our name for it at all. We knew it had sort of hand like structures
but you can imagine that people saw this and Apocalypse or whatever was coming. But there
are a ton of these images in astronomy and I think you just kind of play with it and kind of go
with it. It's another way when it happens to sort of give people a reason to hook them into
explaining what is really going on. This is really a pulsar in the middle of this thing that is
spewing out high-energy x-rays and this is what it is. It's actually not someone reaching. But
things are all over the place. This is the famous Horsehead nebula. Why? Because it looks like
a nebula, some of this is pretty obvious. Some of it is pretty far-fetched, but if you are
interested you can take a look at the last chapter. I did want to sort of end by just mentioning
the book one more time. This is that one. It's in BVC, Sky at Night. We just got a review, which
is fun. And to just mention a couple of other, if you want to learn more about any of this stuff I
will be giving a town hall event on Tuesday about the light book, so it will be not so much about
astronomy as much as it is about the whole electromagnetic spectrum which I need to say
better when I say it that many times. And Travis Rector who was the first author of the
Coloring the Universe book is going to be two times in the next couple of weeks, one at Aida's
which is in Capitol Hill and then he's also giving a talk to the Seattle Astronomical Society
meeting overrun University of Washington's campus and I think that's it. Both of those are
open to the public and are free. I would encourage you if you guys are interested in learning
more of the real nuts and bolts about visible light imagery and all of that to try to get one of
those talks with Travis or if you want to hear more about the light book I encourage you to
come to that once. I will just end by saying this is how you can get in touch with me. I do have
a day job which is the Harvard address and then I have a Gmail account for my stuff on the side
which is basically for the books. With that, I want to thank you and I am happy to take any
questions. [applause].
>> Joseph Ford: People who are watching online can send in questions.
>> Megan Watzke: All right. Here's a question here.
>>: I thank you very much. It's a great book. You mentioned the importance of communicating
the choices of color that were made in a given image. But there often seems to be differences
in the way of doing it. Sometimes it's in text and sometimes it's a color key. Have you explored
having an expanded way of including a color key on the image so that it travels with the image?
Obviously, some of the formats of the images gets transferred around the internet don't have
an easy way of taking that metadata with it, so perhaps including it with a color key on the
image itself could be a useful way, if it's standardized, could be a useful way of helping the
public understand those choices.
>> Megan Watzke: That would be ideal. I would have to say that it's sort of like herding cats
with astronomers. Everyone does their own thing to some degree and there has been a lot of -we are just getting the metadata stuff worked out and having the major observatories
participate. Curtis can talk more about this. I met Curtis years ago with WorldWide Telescope
stuff and part of that is getting the images in a format that is uniform enough that it can be
used in something like WorldWide Telescope and having it consistent. To have a color key on
something that goes out, you are going to have some people who don't want any labels on their
images. There are so many different, and you have people, you have major observatories that
have staffs like ours who will make images and work together with other major observatories.
You also have single astronomers who make a pretty picture and put it out there, so it's really
hard to get that consistency. I think it would really be great to sort of have that template
almost. It's really hard to get there, unfortunately, I think. I think the best we can do is, one of
the things that we've done, for example, on the Chandra website if we do a multi-wavelength
image we always have a clickable layer so you can play with them and stack them and whatever
so you can see what's what. If you see one of these combined images, it's really hard to piece
out what is what and what information comes from what layer. You know, we tried to do it to
what we think is the best standard, but it's hard to get everyone else on the same page is
probably my, unfortunately, kind of non-answer on that. Good idea.
>>: Is there sort of an ordering of the layering that you do or do you always make them opaque
so that you can see through them, or is that important?
>> Megan Watzke: There is not an ordering per se and sometimes, for example, we will make
some layers a little less opaque. So if we're trying to show, for example some of these x-ray
images and we want to put it on a starry background because that makes it look less abstract,
psychedelic, funky, jellyfish floating in the air kind of thing, then we make the, if that star is
really intense it might overpower the x-ray so we might tone down the layer. So there are
choices like that. Sometimes they are all equal. It really depends, but we try -- usually they are
pretty much as they are especially if it's like radio and x-ray, but there are sometimes when we
might tone down the star field, for example or bring up something a little more. Layers are
great for that. Yeah?
>>: I noticed on your layered images that you had of the nebula, the spectrum had slightly
different frequencies. Is that because different scientific teams have to access the different
equipment that actually exposes the different frequencies? Is that why?
>> Megan Watzke: Every observation you request, for Chandra, for example, you are going to
use a certain instrument and you are going to get a certain amount of information back over a
certain wavelength range. And then when you get that information back, some of that
information in various wavelengths is not as useful as others. For example, it gives off very
strong image at a certain wavelength, so you would actually splice out just that wavelength for
that purpose. So it's not that it's different scientists. It's that you are just really using the
pieces of data that make the most sense. Also, with something like Hubble or a ground-based
telescope, you can choose to use different filters. You actually physically put different filters on
the telescope so you are only letting certain light come through. So it really depends on where
the data came from, what it was used for originally. All these data go into public archives at a
certain point so for some of the images you can just pull the best of what looks the best. It
depends on when the image was made and, again, there are a lot of variables that go into it. I
don't know if that answers your question or not.
>>: Yeah, and I guess the follow-up to that, where I was kind of going is if I look at those images
and realize that they are slightly different frequencies, it seems like that would be difficult to
compare and contrast in an apple to apple fashion. But you make it sound like the scientists
actually have much more layering of frequencies available to them so that they can go pull
together the exact slice of the spectrum that they're interested in comparing, the horse head,
the cat's eye, the crab and all of that stuff, right?
>> Megan Watzke: Yeah. Again, there are definitely certain wavelengths or frequencies that
are crucial. Like iron is emitted at a certain line or certain very key frequencies that you have
diagnostic tools that you can use throughout astronomy. It definitely depends on the image. It
depends on the science being done and making the spectacular image is generally not the first
order of business. It's to get the science done. So what we do is we use whatever data we can
get our hands on because the way all these telescopes work is that you propose to a
committee, usually once a year, I want to look at this galaxy for this long with of this
instrument. Give me time and money to do that. And if they get it, great and they are off to
write their paper. And they have that data more or less for about a year and then it becomes
public access data and in the so-called open archives. So it depends on when we do the image.
Sometimes we have only access to that data. Sometimes we can pull stuff from the archive to
enhance the data, but the scientists themselves know exactly how to compare one to another
and how it all fits together. Sometimes we don't have the full range to do that. Yes?
>>: Do you ever confer with experts in save microbiology or other skilled fields who have
similar sort of the eye can receive the details that they are observing? Obviously, they have
different specific intents because they are worried about are there any mission lines per se, but
in terms of just communicating science literacy to the public some of the same best color
questions?
>> Megan Watzke: Yeah. Actually, that's, not to just talk about my book, but some of the
things we have in the light book we talk about that. You definitely have some of the same
issues. You are trying to see the unseen or unseeable and you are trying to explain that. One
example I can share is that Alyssa Goodman who is a colleague of Curtis, she started this whole
initiative with using medical imaging with astronomical imaging and merging those two
together because they are using these techniques to get MRIs of the brain and get 3-D and all
of this stuff. And she helped implement that for astronomical images and we use that for
Cassia PAA [phonetic]. We did a 3-D model. There are definitely ways that we can borrow from
other fields and learn from other fields and I think that is something that we can do more of as
far as merging, using sort of best practices for how to explain these very difficult concepts
across different sciences. An ideal world would be that there was some uniformity so that it's
not confusing to the nonexpert that this time they did it this way and I don't get this. But I think
that is a goal, not really, but we are working on it. I'll put it that way. Yeah?
>>: So you basically are serving up a projection from the wide range that you have information
into something visible. Is there any format now in the digital world or you could just have the
full spectrum sent and you have specific views that you want?
>> Megan Watzke: Are you saying that you want to just pick an object and see it in all of the
different kinds of light?
>>: For example, the red and blue, you could have this view or that view. Nowadays when you
have books you can serve only one. But in digital format you could have different, this shows
the materials. This shows the heat. This shows whatever and have different views.
>> Megan Watzke: Yeah. First of all I have to say as I mentioned earlier, almost all the major
telescopes now have publicly available tools that you can download and grab real data and you
can make your own image in do it yourself. It's a little more work than maybe what you are
suggesting. As far as seeing it and just being able to flip the colors with a switch or a button,
we're not quite there yet. There are tools like with the WorldWide Telescope where you can go
to an object and see every image that has been taken of it in probably not every wavelength,
but most of the wavelengths that are available and you can click through them and see and get
some information as to what the colors are. I'm not sure we're ready yet to just be like show
me what they heat is and show me what this is quite yet, but that would be a really fun tool to
have and it would be informative so you could like say I want to know what this is doing. Talk
to Jonathan Fay about it when he comes back. Tell him you want that tool in WorldWide
Telescope, in his spare time. Yes?
>>: Related to what you were saying, is there, this is definitely getting more technical, but has
there been any effort into perhaps creating a new file format that all it does is format star
images, or even for medical images, layers this information and says this layer contains H alpha
data. This layer contains oxygen data. But the image format, the file format itself has that
embedded in it so it's not [indiscernible]. That would allow you to easily click through and
recolor all of these layers instantly.
>> Megan Watzke: I have no idea. That is not my expertise. That is sort of a Robert Hurt
question. There are people who could answer that question, but I'm not sure about that. It
would be something to consider for sure. Anything else?
>> Joseph Ford: Any other questions? With that, let's give her a thank you. [applause].
>> Megan Watzke: Thanks for having me.