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"LIVE FROM THE STRATOSPHERE" P R O J E CT U P D A T E
PART 1: LFS teacher resources: Web site available, $10 kit at printers
PART 2: Successful test of communications to aircraft in-flight
PART 3: Texas teachers Roger and Todd prepare to fly
PART 4: Roger and Todd do science in the stratosphere
PART 5: NASA Press Release: KAO discovers natural laser
_________________________________________________________________________
Here is a brief report on the status of materials for teachers.
The Web site is finally available for your viewing! The URL is:
http://quest.arc.nasa.gov/lfs
The site is by no means complete; lots more capabilities will become
available over the next few weeks. For now, the best part is the virtual
tour of the Kuiper Airborne Observatory. It can be found under the top
icon called "About the KAO". It has lots of pictures so it will be a challenge
for those with basic connectivity. For the computer adventurers, there is
even an audio file taped from an actual mission.
The Live From the Stratosphere Teacher's Guide and Poster are at the
printers. The page proofs and copy prints were reviewed earlier in the
week. Heat-sensitive paper, spectrum glasses, diffraction grating and
bumper sticker(!) are all in process or en route. So it will be quite a
mini-kit that teacher receive for their $10 investment. To receive the
package, send a check for $10 to: Live From the Stratosphere,
PO Box 1502, Summit, New Jersey 07902-1502.
The Teacher's Guide is not yet online but parts will be available within a
few days; we will announce it here as soon as it happens.
_________________________________________________________________________
Live From the Stratosphere is breaking new ground in establishing
broadcast communications between aircraft and the ground. Geoff
Haines-Stiles reports the following significant steps over the past
few days:
On August 29, between 02:00 and 03:00 Eastern (yes, I had to brave the
streets of New York City to get in to the studio) we did a full video and
audio test downlink from the KAO, in flight at 41,000 feet. We rolled
video and the Texas teachers demonstrated some hands-on activities
(balloons in bottles, Geiger counter) that may become part of a video news
release, or the programs.
In the air was Wendy Whiting (the overall planner of the project for NASA
and the Mission Director on our flights) and Allan Meyer (astronomer and
flight planner). I was in the studio in New York and George Benaman was
at the Maryland Public Television facility. We chatted back and forth to
show that we could break down and re-establish comms. links between
two land sites and the aircraft. Audio and video were both good, though
cameras are still to be tweaked and adjusted. Audio was noisy -- especially
when people left mikes open by accident -- but very acceptable. And just
to ensure we don't get too smug, we lost the last 5 minutes of our satellite
time because the computer, in Princeton, NJ, which controls the steerable
beam on the satellite, crashed. It was down for 30 mins ("never happened
before... we didn't know what to do...") but we are assured that the
satellite will be steered BY HAND if the same thing happens during our
two live flights! Cottage computer handling in the age of Info -- Irony!
But it should serve as a useful warning against techno-hubris. Along with
the audio and video, the coordination channel, via an Airphone, is just as
important, as a behind-the-scene link, and that also was working.
The next test is a full dress rehearsal, on the ground, Monday Oct 2nd, then
in the air, Oct 3rd, then a walk-thru of program Oct 4th, then SHOWTIME --
October 5th!
_________________________________________________________________________
[Editor's note: the following entries are excerpted from a series written by
Roger and Todd which document their adventure in flying onboard the
KAO. They will continue for another week. Complete info can be found on
the Web at http://marple.as.utexas.edu:80/~WebSci/]
Science in the Stratosphere - Journal
Roger Stryker - Monday, August 21, 1995
Greetings and welcome to my first journal! With a week to go before
the first flight, I'd like to introduce myself and my partner, Todd
McDowell. I'll write more about Dr. Dan Lester, the astronomer that is
responsible for our adventure, Science in the Stratosphere, later.
Besides the men and women, scientists and technicians, that we will meet
and work with, we are the three main characters in this adventure.
In my 16th year as an elementary educator, I currently teach 5th grade
at Williams Elementary in Austin, Texas USA. This year, Williams has
begun the 1995-96 school year with an enrollment of close to 1,000
students. My 5th grade class has 29 students, 16 boys and 13 girls. We
are one of six 5th grade classes at Williams.
My partner in this adventure and fellow Austin educator, Todd McDowell,
teaches 6th grade at Zavala Elementary. He is currently involved in a
program to encourage and prepare minority students for entrance into the
science magnet program at Austin's Kealing Junior High.
Science in the Stratosphere - Journal
Roger Stryker - Thursday, August 24, 1995
Today I will give you an idea of what is planned for Todd and I so far.
Just last night I spoke long distance with Isabel Hawkins who is a
scientist/astronomer with Eureka Scientific, a company that is working
with the Exploratorium (a great San Francisco science museum) to conduct
some investigations on a future Kuiper flight. We will be conducting the
same investigations to give them a "dry run" of their project.
On our first flight, Monday, August 28, Isabel has us testing two
explorations they will be doing on their future flight - one with a Geiger
counter and the other with bubble gum during take off and the ascent.
For the second flight, Thursday, August 31, we will have a list of
investigations, the most unusual of which is attempting to boil an egg
with an immersion coil at 41,000 feet. We will also be observing a
balloon secured to the mouth of a 2-liter bottle and recording the weight
of selected items. These explorations have to do with the gravity and
atmosphere here on Earth, not with the astronomy being done by the
scientists on the KAO. During these experiments, we'll be communicating
live and in color to the Exploratorium, using new Apple Computer software
called Quicktime Conferencing. This will be cool!
The only other items scheduled for the whole week, besides the two
flights, are the briefings before the flights, at 1:00 p.m. sharp the day of
each flight, and an oxygen mask fitting Monday before the first flight. No
mention was make of a parachute fitting - I feel good about that.
_________________________________________________________________________
Science in the Stratosphere - Journal
Roger Stryker - Tuesday, August 29, 1995
There we were at 41,000 feet with events going well. All of the
investigations we did for the Exploratorium at take-off and during ascent
did what we had expected - that is, all except for the bubble gum. Our
brains buzzed from the excitement, as well as the reality of what we were
doing.
First, and most importantly, Dan and his team of astronomers worked to
sight objects and collect electronic data as the C-141 followed a set
course across the sky over the western United States. The pilots flew the
Kuiper to follow the long legs of Dan's flight plan, allowing the
telescope, exposed to the frigid air in a specially built cavity in the
side of the plane, to view each celestial object for a set amount of time.
The hole in the plane is on one side, so the flight plan needs to have the
plane going in the appropriate direction in order to view a given object.
Many objects are viewed during the course of a flight, so the flight plan
has long straight stretches followed by turns, sometimes relatively sharp,
in order to get the most out of a single flight. Airborne astronomers, as
they plan the long stretches and quick turns of a flight, need to take
into consideration such things as restricted air space over military
bases, as well as tailoring the plan such that the last observation will
bring them relatively close to home after a 7 hour flight.
We watched in fascination as a technician used his instruments to find in
succession each target object in deep space - actually using objects that
can easily be seen on his monitor to find the very faint target objects
for the astronomers.
All the while, a team of technicians worked intently on live audio and
video communications between the plane and a television station on the
east coast using the satellite connection that will, later this fall, make
"Live from the Stratosphere" just that - live. On the plane we are able
to use that same satellite connection for the Internet. We even surfed
the Internet just as we would from our classroom - the only difference
being that we're bouncing the key commands from the computer off of an
orbiting satellite!
A great thing happened while I was logged in sending off electronic
"postcards" from our connection to cyberspace from high in the
stratosphere. I knew it was sometime after midnight in Texas. My wife,
my kids, and my students were all in their beds sleeping, getting rested
for their second day of school this week. I received a message - it was
David in Tasmania.
Finished with his day, students gone home, he wrote, "Just guessing that
this may find you 'UP IN THE AIR'. Can you see Tasmania from up there?
Look out the Westerly window!!!!"
Well, of course I was up in the air, and even more so after seeing this
message! Here was someone with whom I could share my excitement - someone
that was awake! We exchanged a message or two, and around 4:30 p.m.,
his time, he inquired as to how the gum chewing went. Unfortunately, I
couldn't stay at the machine as I had some things to do. But, David, here
is the gum report.
The bubbles didn't do what I had expected. First of all, it looked kind
of gross sitting there, with a bubble hanging off the wad, stuck on the
top of the metal storage container in front of me! Time was important as
all the investigations had to be done during take-off and ascent. That
made for a busy first several minutes of our flight.
One of Dan's graduate students, Eric, was helping out - he chose Super
Bubble. Actually, I'm not sure what brand Todd chose, but he never did
get a workable bubble (he was a bit distracted recording data from
observations of the balloon bottles and the numbers from the Geiger
counter). At one point, I turned and saw a bubble remnant strung between
his mouth and his headset microphone. I really didn't have time to laugh,
but it was kind of funny. I was working on my own product from good ol'
Double Bubble (Cheryl Patrick's class, the Shooting Stars, in Canberra,
Australia suggested it might be renamed "Hubble Bubble"). Eric and I
figured out early on that it'd take two pieces to get a workable bubble,
so I was chewing madly, shooting out practice bubbles for some time...
Anyway, to make a longer story short, the bubbles attached to Eric's and
my wads of gum sat there unchanged as our other pressure related
investigations produced interesting visual results.
There's so much to tell, I'll try to fit it all in time. The bubble
gum was an important item on the agenda, however. Even the astronomers
speculated on the possible results. An important lesson in all this, as
Dan pointed out, is that not all science investigations produce successful
or expected results. But then, maybe we just didn't do something right.
We'll give it another go Thursday to see if we missed something - this
time with Bubblicious.
Here is an answer to one of David's questions about how we breathed high
in the stratosphere. We had to be fitted for oxygen masks as a safety
requirement and had them available in case of an emergency. The cabin was
pressurized to a point that would be similar to standing on a mountain at
around 8,600 feet. The little bags of chips we brought to observe were
blown up like balloons!
Science in the Stratosphere - Journal
Todd McDowell - Tuesday, August 29, 1995
Last night was more excitement than I could have hoped for. We not only
got to watch some very dedicated scientists work under very special
circumstances, but we also had a chance to do some exciting experimenting
of our own.
My most outstanding impression of the flight was the sight of this crew of
five guys working together as if they were a single person. They were all
so intent and focused on their purpose that it was really special to
watch. The team is led by the principal investigator (PI), who is the
person that writes the study and has the questions that need to be
answered by the investigation. He is the boss of the crew and gives
directions to all the other members based on the information that they
give him.
Another member of the crew is the tracking operator. He is the one who
finds what we are looking at through the telescope and keeps us on the
the target. If he cannot find the right place in the sky, nothing that
the rest of the crew does will be of any use.
Right nearby these two members were another pair whose job was to move
the telescope and to tell the PI how good the information is that they
are getting from the object they're looking at. Many times during our
flight the PI would consult with these two operators to determine what
changes to be make in the direction of the telescope.
The last member of the telescope crew logged down information that
would later be an accurate record of exactly what was done when. This, of
course, is very important for all experiments so that others can
duplicate or test out the discoveries that the original team made. If
there is any question of what was done during the night's flight, this
record is checked.
Also on the flight is the flight crew. These people are trained to make
sure that plane goes up, operates and lands safely. There were three of
this team up in the cockpit, flying the plane, and three more back with
the astronomers, making sure that the plane was where the astronomers
needed it to be in order to see what they were looking for.
On our flight there was also a crew who was working with the video and
audio connection to people back on the ground. They were busy during
most of the flight setting up, testing, and later, taking down their
equipment. Because of their efforts, Roger and I were able to be seen
and heard at a TV station in Maryland, and later to be seen over the
computer in the science museum, the Exploratorium, in San Francisco.
There are so many thoughts I would like to share with all of you
following this incredible experience but most of all, I would like to give
you some idea of what it looks like to watch scientists at work.
In some ways, the space we were in reminded me of a classroom. Even though
this airplane is fairly large, it was actually quite crowded by the time
all the crews were on board and at work. This is because there is so much
equipment that is necessary to do this kind of task. As it turned out,
there were small groups, as I described above, working on their individual
projects, but *all were working to accomplish a single goal* - in this
case, fly the plane to get the data. This is what made it seem like a
classroom to me.
What was amazing was how much could get done when everyone works together.
Often the instructions would go from the PI to one of the astronomy crew
and he would send his own message to another crew member, who would report
back to the PI. The PI would then give a new set of instructions and the
process would repeat itself, all faster than the time it takes to tell you
about it.
I think that this is especially important on this kind of mission because
these astronomers have planned for months to figure out exactly what they
are going to look at and when. Then they are given less than eight hours
to do it all, with no chance to "go back and do it again" if something
goes wrong. Therefore, they must make the most of their time in the air
and any disagreements they might have must wait for later. Cooperation
on a Kuiper flight, just like in a classroom, brings good results.
I want to tell you a little bit about some experiments that Roger and I
performed while up in the plane. We were given the assignment to try out
some equipment whose purpose was to test the effects of air pressure as
we went up higher in the atmosphere. As you know, air has weight and it
pushes down on us with that weight when we are down here on Earth. But
just as the water pressure is greater at the bottom of the deep end in a
swimming pool, so this air pressure is greater at the "bottom" of the
atmosphere where we live than it is up higher, where we were flying in
the Kuiper.
I will tell you how we set up some of our tests. Then I would like you to
tell me what you predict, knowing what you know about air pressure. Most
of what you need to know is in the paragraph above. The only clue I will
give you is that the results were predictable from the concepts given
above.
I. Balloon in a Bottle (Part 1)
I took a two-liter Coke bottle and poked a hole in the bottom. Then,
right before the plane took off, I pushed a balloon down into the bottle
and, leaving the open end sticking out of the mouth of the bottle, I
inflated the balloon and tied off the end. Then I watched the balloon
carefully as the plane took off and recorded any changes. What do you
think happened?
II. Balloon in a Bottle (Part 2)
For this experiment I used a special two-liter bottle given to us by one
of the employees at the Exploratorium. He had put a hole in the side of
the bottle about two inches above the bottom and hot-glued the top of
another bottle into the hole. This allowed me to unscrew the top of this
opening, which would let air into the bottle through its own top and the
new "top" on the side. I then uncapped both tops, pushed a balloon down
the "real top", stretched the end of the balloon over the opening and blew
it up inside the bottle. Once I had some air in the balloon, I quickly put
the cap on the new "top". When I took my mouth off the balloon, it
remained inflated inside the bottle. Why?
I then watched this bottle also during takeoff and ascent and recorded
any changes. What do you think happened to this balloon?
Later, I will let you know what I saw happen to the balloons. Stay tuned
for a future update when I tell you what happened when we took a Geiger
counter up with us.
_________________________________________________________________________
Don Savage
Headquarters, Washington, DC August 29, 1995
(Phone: 202/358-1547)
Diane Farrar
Ames Research Center, Mountain View, CA
(Phone: 415/604-3934)
RELEASE: 95-148
SCIENTISTS DISCOVER FIRST NATURAL LASER IN SPACE
The first "natural" laser in space was detected by scientists on board
NASA's Kuiper Airborne Observatory (KAO) as they trained the aircraft's
infrared telescope on a young, very hot, luminous star in the constellation
Cygnus.
Discovery of this naturally occurring laser provides scientists with a
powerful tool for probing the conditions in disks of gas and dust
surrounding young stars, according to Principal Investigator Vladimir
Strelnitski of the Astrophysics Laboratory, National Air and Space
Museum (NASM), Washington, DC, who made the discovery. Scientists
believe that many of these circumsteller disks are regions where planets
are forming.
The laser is created as intense ultraviolet light from the star "pumps" or
excites the densely packed hydrogen atoms in the gaseous, dusty disk
surrounding the star. Then, when the infrared light shines on the excited
hydrogen atoms, it causes the atoms to emit an intense beam of light at
exactly the same wavelength, creating the circumstellar laser, according
to Sean W. J. Colgan of the Search for Extraterrestrial Intelligence (SETI)
Institute, Mountain View, CA, a co-investigator in the discovery.
The discovery was made as the KAO, the world's only flying observatory,
returned to Moffett Field, CA, from observing missions based in Hawaii.
Co-investigators in the discovery are Howard A. Smith, also of NASM;
Michael R. Haas and Edwin F. Erickson, Ames Research Center, Mountain
View, CA; and Colgan.
Strelnitski used a sensitive liquid helium-cooled spectrometer attached to
the KAO telescope to search for selected "lasing lines" in the infrared
region of the spectrum between 50-500 microns (100 to 1000 times the
wavelength of visible light).
The natural laser was detected at 169 microns as the scientists viewed the
nearly edge-on gas and dust disk surrounding the peculiar star known as
MWC 349. The "lasing line" has an intensity six times brighter than non-
amplified spontaneous emissions at the same wavelength, Strelnitski said.
The existence of natural lasers was predicted more than 15 years ago,
following the successful amplification of both microwave and visible light
wavelengths in laboratory experiments, and the discovery of amplified
microwaves in space.
American physicist and Nobel laureate Charles Townes first proposed the
practical amplification of electromagnetic radiation by stimulated emission
in 1951. In 1954, his group at Columbia University created the first
laboratory amplifier of microwaves, calling it a MASER (Microwave
Amplification by the Stimulated Emission of Radiation.)
In 1960 Theodore Maiman at Hughes Research Laboratories developed a
device to amplify visible light, creating the first LASER (Light
Amplification by Stimulated Emission of Radiation.)
Not long after the invention of laboratory masers and lasers, the first
natural masers were discovered in interstellar and circumstellar gas
clouds. Townes, a frequent investigator onboard the KAO, was among the
discoverers of the first strong astrophysical water masers.
Astrophysical masers, due to their extremely high intensity and spectral
purity, are valuable tools in studies of the birth and death of their
associated stars. On Earth, many scientific and industrial applications of
masers and lasers have been developed, such as keeping exact time, bar-
code reading in supermarkets and performing "bloodless surgery."
Astrophysical masers can be observed from the ground with special
instruments, but the major part of the infrared spectrum where potential
lasers might be seen is hidden from the ground observer by Earth's
absorbing atmosphere.
This long awaited discovery of a natural laser was made on the last
scheduled flight of the KAO instrument -- the Ames Cryogenic Grating
Spectrometer. The instrument permits sensitive detection of emission from
atoms and molecules throughout the mid- and far-infrared spectral
domain.
The KAO is scheduled for retirement this fall. NASA plans to begin
development of the follow-on airborne observatory SOFIA in 1996, with
first flight scheduled for the year 2000.
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