"LIVE FROM THE STRATOSPHERE"          P R O J E CT  U P D A T E # 21

PART 1: Television history: a unique experience for many of us
PART 2: Please share your media coverage
PART 3: A Brazilian occultation adventure
PART 4: April gets ready for the first TV broadcast
PART 5: Astronomers don't always look through telescopes

_______________________________________________________________________

Some (exhausted but pretty pleased) words from Executive Producer and
Project Director Geoff Haines-Stiles:

PHEWWWWW! Seven and a half hours of live television in two days! NOT your
usual sort of program schedule, but then--in the PASSPORT TO KNOWLEDGE
project--live video and tape are delivery mechanisms for experiences,
more than traditional tv programs. That's why we call PASSPORT a series
of "electronic field trips": the video is designed to deliver faces and
places and processes to personalize and dramatize that higher level of
information and interaction to be found online, and to climax the hands-on
learning suggested by the printed materials distributed in advance.

That said, this week's video was SPECIAL... and we hope you realize you
were part of television history.

This was the FIRST-EVER two-way video to a plane in flight, involving
technological wizardry, courtesy of NASA's Advanced Communications
Technology Satellite, and much hard work from NASA's Jet Propulsion Lab,
Lewis Research Center and Lockheed Martin, New Jersey. It was
state-of-the-art technology deployed not for missile systems but to serve
education--an encouraging precedent, and a tribute to America's teachers
and students. Congratulations, ACTS team, and thanks.

Second, the KAO team, together with teacher April Whitt from Georgia,
students Brian Scott from Texas, and Laura Smith from California, showed
that it was possible to have students travel with them via technology
during a scientific research mission, and look over their shoulders. This
was REAL SCIENCE, REAL SCIENTISTS, REAL LOCATIONS, REAL TIME.
And we're delighted to find that "boys and girls of all ages"
found this REAL exciting! Again, this is a precedent for future NASA
missions, specifically SOFIA, the KAO's successor, but more generally for
trips to Mars and beyond! Let us know how it worked for you and your
students.

Lastly, it prototyped what we hope will be part of future PASSPORT
projects, a network of participants in schools and science centers,
accessing the video through whatever means possible--PBS station, NASA
TV, cable company, junior college (we should probably publish a book of
"war stories"/tips for next time--about how people eventually obtained
the tv signal!) in order to structure an event customized to reflect local
circumstances. PASSPORT proposes a menu of possibilities: local sites
choose and execute what they think will work best for them. That sounds
right no matter which political party and philosophy you support!

So, thanks for your participation  and interest. On to the last video
program, but it's important to remember that the online components remain
LIVE through November 17, and that there are many activities--star count
follow-ups, KAO position plotting from the archived data--that can help
tapes and text COME BACK TO LIFE for students in the months ahead.

AND PLEASE... THINK ***EVALUATION*** EITHER USING THE FORMS IN THE PRINTED
GUIDE, OR ONLINE! WE WANT TO KNOW THE RESPONSES OF YOU AND YOUR STUDENTS
IN SOME DETAIL, TO HELP STRUCTURE OUR NEXT ELECTRONIC FIELD TRIPS!

So, still, Onwards and Upwards
Geoff Haines-Stiles

_______________________________________________________________________

This is a CALL to each of you to help us document our collective LFS
experience. In a few weeks, we will be asking folks to help evaluate
the program. For now, we would very much like to obtain copies of
media coverage of the Live From the Stratosphere project. We ask
that anyone who is aware of coverage of any type (newspaper,
TV, etc.), PLEASE submit the articles and send video tapes
of your event coverage to:

PASSPORT TO KNOWLEDGE, 41 ROWAN ROAD, SUMMIT, NJ 07901
Phone: (908) 273-4108.

_______________________________________________________________________

A BRAZILIAN OCCULTATION ADVENTURE
By Ben Burress, Tracker Operator

Working on the KAO is not just working on the edge of the stratosphere,
but sometimes simply on the edge. One mission in particular could
have held its own in the box office for sheer edge-of-the-seat
excitement.

Once in awhile an astronomer desires to observe an event called
an "occulatation". An occultation is when a planet, asteroid, or
comet passes between Earth and a star, casting its shadow across
the face of our planet. Astronomers take advantage of this
celestial alignment by observing the light from the star being
occulted and measuring the effects of the occulting body's
atmosphere, if any, on that starlight. By measuring in what manner
the starlight dims as the two objects get closer together,
astronomers can determine things like the temperature or the
density or the structure of the occulting object's atmosphere. Or,
for a body with no atmosphere, a precise size measurement can be
made by measuring how long it takes for the star to disappear and
reemerge. At any rate, occultations are the most exciting types
of missions on the KAO as far as the criticality of timing and
positioning of the aircraft, and the fact that the occultation event
lasts for mere seconds.

One particular occultation mission stands out in my mind because of
the many hurdles we went over and the numerous times the entire mission
was stopped dead.

The object that our astronomers predicted would occult a star is
a comet called Chiron, orbiting the sun in the outer solar system.
The objective of the astronomers, Dr. Edward Dunham of NASA Ames
and Dr. James Elliot of MIT, was to study the nature of the halo of 
material outgassed from the comet.

To encounter the shadow of this particular occultation we had to
fly over the Atlantic Ocean off the coast of Brazil, at precisely
the correct time in precisely the correct location. The shadows
of small, distant objects can be hundreds of miles across, but move
over the face of the Earth at many miles per second, and therefore
the events do not last very long.

We took off from Ames one day in March, 1994, and flew to Puerto
Rico, where we spent the night in preparation for our "practice
flight": a flight from Puerto Rico to Brasilia, Brazil during which
we observed the star that would be occulted a few nights later.
This was to become familiarized with the star field as much as it was
for the astronomers to gather some data on the star's light. Our
first hurdle was still in place when we took off from Puerto Rico:
we had still not been granted permission to land in Brazil, or fly
over its air space. I understand that the permission was granted
while we were in flight, and we landed in Brasilia on schedule.

Our next hurdle seemed to be to convince the Brazilian military
leaders that we were not, in fact, flying over their country with
a huge infrared camera in order to spy on them, but to watch a ball
of dirty ice fly in front of a star. All along, the leading
military officers were dead set against our very presence in Brazil,
and probably the only reason we were able to gain admittance to that
country was the fact that Ted Dunham had been in close correspondence
with a leading Brazilian astronomer, who went to bat for us. In the
end, we were tentatively allowed to fly our mission, but we had to 
submit our flight plan a couple days in advance and promise not to
deviate from it.

There we were, sitting in the KAO at the airport, engines running,
buckled in our seats, all ready to go, when the tower suddenly
denied us permission to take off. On board we had two Brazilian
guests, Ted Dunham's astronomer associate and a Brazilian Air
Force major. While the former had saved our day a couple of times
already, it was our other guest who now went to bat. The major
talked to the tower for at least five minutes, and discovered that
the reason we had been denied permission was because the flight
plan we had filed earlier that day "differed significantly from the
one we had provided two days earlier." The major consulted with
Dr. Elliot concerning the reason for the change, which was mainly
due to the fact that the newer flight plan was based on more precise
position data on the comet, Chiron (the closer an occulting body
comes to the star it will occult, the more precisely the position
of its shadow's path on the Earth can be calculated; sometimes the
difference can be enough to influence a flight plan). The major
came through for us, and convinced the tower to let us take off.

The flight itself went very well. Of course, any number of things
could have happened to spoil the entire week-long mission; any piece
of telescope equipment could have failed, even momentarily, at the
wrong time, causing us to lose everything. The tracker might
have failed, a camera, the telescope systems, power, compressors,
autopilot, etc., etc., etc. This is why this sort of mission
is so nerve-wracking. A lot of time and money go into getting the
airplane to a remote location, obtaining diplomatic permission,
transporting personnel and equipment, and it can all come to nothing
if the smallest thing goes wrong at the wrong time. For an event
that lasts only ten seconds, a simple loss of track, when for
one reason or another the tracker computer temporarily loses track
of the track object, could have wiped out everything.

In the end, the mission was a success, despite all of the potential
show-stoppers that reared up along the way.  By this time, it was
no surprise to anyone when, only hours before our departure from
Brazil, we had still not obtained diplomatic permission from the
Chilean government to land
at our intended fuel stop on Easter Island....

_______________________________________________________________________

GETTING READY TO BROADCAST
April Whitt

Monday, October 2, 1995
It's rehearsal day - or the first day of rehearsals, anyway. Remember
to wear closed-toe shoes! (I knew that, but still had sandals on, and
was reminded at least six times by various crew members. The Kuiper
is full of rails, metal corners and racks on which to damage one's
unprotected feet. As it is, a helmet would have been more useful today
- I cracked my head a good one on the door frame, climbing out of the
plane this morning. No blood, no foul though.)

During a 10:00 am meeting with Wendy Whiting and other NASA people
I get a glimpse of just how much effort has already gone into this
project. For months, this support team has been working hard,
organizing, discussing, planning and re-planning, solving the problems
- they've done a great job!

Different people report on concerns still pending: "Will I need a car in
Houston?" "Where's the airphone and when will it be back from its
modifications?" "What about that long cable for the camera?" Walt and
Juan give updates. Mr. Haines-Stiles wants a production meeting every
day.

Afterwards, Allan Meyer describes the process of choosing a flight
path that matched the dates of broadcasts. One limiting factor is the
ACTS (Advanced Communications Technology Satellite). Its orbit
carries it through the Earth's shadow (shutting it down) at only two
times of the year - close to the equinoxes. At other times it misses
the shadow or only goes through a small portion of it. While in the
shadow, its solar panels are inoperable and it shuts down. The
broadcast dates unfortunately fall in that time frame when the
satellite will shut down early in the morning (or late at night
depending on your time zone).

So there are all kinds of variables to consider. What objects do you
want to view? At what seasons of the year and times of night are they
visible? When do they rise high enough above the horizon for the KAO's
telescope to acquire them? Are those times reasonable for a broadcast
that begins on the East coast? (no - which is why we leave from Ames
or Houston)

Houston's time zone is a better one, but the disadvantage of an east to
west flight is that the telescope, pointing out the left side of the
place, will always point south. A problem if you want to see something
in another part of the sky. So the flight path will zig and zag to get
everything in. Sometimes when an object is not real high in the sky, the
pilots can even tilt the plane a bit to allow the telescope to better
pick up an object.

The objects for Friday's flight include: 

M17 (sometimes called the Omega Nebula) It's in the constellation of
Sagittarius and is visible even in bright twilight, so we can take off
before the sun's completely set and still acquire it. There are a few
bright stars nearby to help find it.

W51 - a star forming region halfway across the galaxy (much further
than M17). It's still bright in the infra-red, but the visible "finding
stars" are much dimmer.

Bernard 335 - Jackie Davidson wants to get some more data on this
star. It may be variable, but she needs more information to
corroborate.

M57 - the Ring Nebula. An older star that has puffed off its outer
layers of gases, which are expanding in a bubble. From Earth the bubble
looks like a ring around the leftover shrinking star in the middle,
hence the name. Some dust has formed inside the bubble and may be
detectable in the infra-red. M57 is also labeled NGC 6720.

Saturn - a calibration object. But maybe we can see the moon Titan as
well.

M33 - a spiral galaxy that has a fairly bright star-forming region.

Then the satellite shuts down, so we can't talk with groups on the
ground any more.

That's quite an impressive array of objects. The "M" designation is for
Messier objects. Charles Messier was a French comet-hunter. During
his sky-scanning sessions, he kept finding brightish blobs with his
telescope, but they weren't comets. He started listing them in a
catalogue so he wouldn't waste time on one the next time he ran
across it. M17 was the seventeenth object on his list. The Messier
objects are fun to find today - galaxies, nebulas, clusters: all kinds
of pretty stuff.

NGC is the abbreviation for New General Catalogue, but I think the
"new" is relative. I think Herschel set it up over a hundred years ago.
Check that, though.

Allan has been working with the KAO for about 15 years or more. He
has a collection of finding charts that help him acquire and track an
object. They're carefully drawn charts on paper and some plastic
overlay sheets (that he can put up against the screen where the
tracker camera's image is showing).

The acquisition camera (or "ack" as it seems to be called) has a zoom
lens that can bring in from 3 to 12 degrees of the sky (helpful if one
gets lost on a star field - zoom out a bit and get a perspective). The
tracker camera has a much smaller field of view - only half a degree.
The telescope tracker's job is to keep the object in the tracker
camera's field of view while the research people guide their array to
look at the object. On these flights, the detector array will look at
several small parts of a galaxy (M33 for example) rather than the
whole object.

After all this information, it's time for more. Walt Miller explains how
to use the black headsets that will be worn during the broadcast.
They're a recent acquisition, and there aren't enough for everyone to
have one, so we'll have to share. There are three places in the plane
they can plug in, and the wires only stretch so far. The producer's
voice and directions will come in our right ears (on the cue channel).
We'll hear ourselves and the rest of the broadcast in our left ears
(program channel) and there's a little "pot" on the bottom of the
beltpack to adjust the volume of the questions coming up from the
ground, also in our left ears. That makes at least three conversations
to track, while one is talking to the camera at the same time. And be
aware of which channel is which, which "push to talk" button is which,
and try not to turn the cue channel volume down so you can't hear
directions.

We are assigned seats in the KAO and try out the headsets. Here on the
ground it's fairly easy to keep track of what's going on, but I don't
recognize people's voices yet, and have trouble telling who's talking in
the headset. We skip back and forth between program and cue channels,
and Juan offers to label the different buttons. Thank heaven for Juan
and his television experience! His calm, collected attitude and Wendy's
professionalism keep us better on track. Brian Scott (student from
Houston) and Laura Smith (student from Los Altos High School here in
the San Francisco Bay Area) will arrive tomorrow for the short
practice flight.

_______________________________________________________________________

CHASING METEORITES IN ANTARCTICA
Dr. Scott Sandford

Part of my research work at NASA involves the study of meteorites.  
Meteorites are pieces of rock that fall onto the surface of the Earth 
from outer space. Most meteorites are thought to come from 
asteroids and were probably originally flung into space during the 
explosions that result when asteroids collide with each other.  
Strangely enough, my interest in meteorites has taken me all the way 
to Antarctica. It may seem a bit surprising, but the world's coldest 
continent is also the world's best place to find meteorites. This is 
largely because the ice and snow preserve meteorites for up to a 
million years. In contrast, meteorites that land on other continents 
rarely last more than a few hundred years before they are plowed 
under, paved over, eroded beyond recognition, or lost by some 
other process.

Meteorites that fall in Antarctica are slowly buried in snow. As this 
snow accumulates the weight of the snow on the top squeezes the 
snow below so hard that it turns into ice. Once the meteorites are 
encased in ice, they are protected from destruction. The meteorite-
bearing ice flows very slowly down hill, usually until it reaches the 
ocean. At the ocean, the ice breaks off into large icebergs which 
float out to sea and melt. Thus, most of the meteorites that land in 
Antarctica ultimately end up getting dumped into the ocean where 
they sink to the bottom. However, there are areas in Antarctica 
called "ablation zones" where meteorites can be collected before they 
get into the ocean. Ablation zones are locations where the large 
moving masses of meteorite-bearing ice run into some kind of 
barrier, mountains for example. These barriers thrust the ice 
upward where it is exposed to the constant winds that blow in 
Antarctica. These winds wear away the ice by ablation and expose 
the trapped meteorites. [Ablation is a process where a solid material 
evaporates without first becoming a liquid. This is the same process 
that makes your ice cubes shrink in a 'frost-free' freezer!] In a 
sense, the flowing ice is a large conveyor belt that collects meteorites 
from large portions of Antarctica and delivers them to the ablation 
zone where they accumulate and can be collected by scientists.  
Some of these special Antarctic locations contain huge numbers of 
meteorites. One year I participated in a search expedition that found 
over 1000 meteorites in six weeks!

There are many types of meteorites. Most meteorites that are found 
are of a relatively common type known as "ordinary chondrites."  
While all meteorites are of scientific interest (they can tell us a lot 
about the formation and subsequent history of our Solar System), 
people who study meteorites are especially interested in the rarer 
types of meteorites because they have generally been less well 
studied and are more likely to teach us new things.

Here's how we search for meteorites in Antarctica. Each "morning" 
(since we search during the Antarctic summer the sun never actually 
sets while we're there), the men and women of the search party, of 
which there are usually 4 to 8, leave their tents and go out on foot or 
on snowmobiles to search. In good locations, the ice field being 
searched is created by a submerged mountain. This type of ice field 
is usually uncontaminated by terrestrial (i.e., Earth) rocks. It 
doesn't take a lot of skill to find meteorites on this type of ice field.  
Anything that isn't snow or ice is probably a meteorite.

Unfortunately, many ice fields are found near exposed mountains 
and the meteorites are mixed in with a lot of terrestrial "junk" rock.  
Finding meteorites on these fields requires that every rock be 
painstakingly examined to see if it's a meteorite.

You can usually tell whether a rock is a meteorite just by looking at 
it. Most meteorites have a distinctive black coating called a "fusion 
crust." The fusion crust is created when the surface of the meteorite 
is vaporized by the intense heat generated when the meteorite enters 
the Earth's atmosphere.

However, one of the problems you have to deal with is that you 
occasionally stumble upon a 'mystery rock' that might be a 
meteorite... or it might not. Of course, these rocks may be the most 
exciting finds of the expedition because they potentially represent 
new and unique meteorites. Or they might be "junk" rock.

In the most ideal of all worlds, you should simply collect everything 
you're not sure about, the theory being that it's better for the 
curators at Johnson Space Center, who later examine the samples 
more carefully (and who are relaxed, warm, and have lots of time), 
to sort it all out rather than have the expedition members (who are 
cold and tired and have limited time) agonize over it.

In practice this does not always happen because: (1) to collect a 
meteorite, package it properly, record the data in a field book, etc., it 
is necessary that the scientist remove his or her gloves and risk 
freezing their fingers, and (2) because all the members of the 
expedition consider themselves to be immensely important 
meteoriticists and do not want to be exposed to possible ridicule 
should the people in Houston discover they have accidentally 
shipped them a penguin dropping or some such item.

So what to do? Generally, the expedition members gather around 
the rock and "discuss" whether it should be collected or not. This 
generally solves the problem, either because some consensus is 
reached or because someone finally decides it would be less painful 
to remove his or her gloves than to continue to listen to the 
"discussion."

In late January of 1989, I and three colleagues were searching for 
meteorites near the MacAlpine Hills in Antarctica. The weather was 
VERY cold and the ice field we were searching had a fair amount of 
terrestrial "junk" rock on it. We had already found a few meteorites 
when I came upon a 'mystery rock.' It did not look like a terrestrial 
rock of the type local to the area, and yet it didn't look like a normal 
meteorite either. Most meteorites look black, but this rock was a 
funny sort of greenish-brown. On the other hand, the surface of the 
rock had the characteristic smoothness of a fusion crust, as if the 
rock had entered the Earth's atmosphere at a very high velocity.

After some discussion, the four of us were unable to come to a 
consensus about whether the rock was a meteorite or not, but I was 
reluctant to leave it behind. It was finally decided that I would put 
the rock - which weighed about one and a half pounds and was 
about the size of a fist - in my pocket. If no other rocks of this type 
were found, I would bag the specimen for Houston. If we began to 
stumble onto many more rocks of the same type, we would 
conclude that we had drifted into an area with a new kind of 
terrestrial rock and I would throw the rock away. On this note, the 
discussion was closed and we continued with our search.

So of course we found one more such rock, a smaller one, and the 
"discussion" was renewed. This time I finally decided that the 
discussion was getting to be too frustrating so I bagged my 
specimen. The smaller sample was bagged soon thereafter.

This proved to be a smart move.  Several months later, when I was 
back at work at NASA's Ames Research Center, I received a call 
from someone at the curatorial facility at the Johnson Space Center.  
They wanted me to know that both of the 'mystery rocks' had 
turned out to be lunar meteorites. Yes, pieces of the Moon! So 
apparently, some time in the last 10 million years or so, a large 
asteroid or comet hit the Moon and the resulting explosion ejected 
pieces of the Moon into space. Some of these pieces ended up 
falling on the Earth as meteorites. Some of these landed in 
Antarctica and one of them came to the surface of the ice just in time 
to spend a day in my pocket.

So..., the next time you're worried about doing something that may 
expose you to potential ridicule, you might just stop and ask 
yourself, "How many penguin droppings are worth one lunar 
meteorite?"