LIVE FROM THE RAINFOREST Update May 8, 1998 Volume 7, Issue 24
From: Geoffrey Haines-Stiles
Subject: LIVE FROM THE RAINFOREST Update May 8, 1998 Volume 7, Issue 24
Date: Fri, 08 May 1998 10:09:35 -0400
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LIVE FROM THE RAINFOREST Update May 8, 1998 Volume 7, Issue 24
FLASH ALERT! TODAY, FRIDAY MAY 8TH OFFERS MULTIPLE CHANCES TO VIEW LFRF
PROGRAM 2!
###
Table of Contents
LIVE FROM THE RAINFOREST: still interactive after all these months...
LFRF & LIVE FROM THE POLES re-runs on NASA-TV
***FLASH ALERT! TODAY, FRIDAY MAY 8TH OFFERS MULTIPLE CHANCES TO VIEW LFRF
PROGRAM 2!***
Challenge Questions: check out the Questions and Answers online
Backyard Biodiversity Survey: still time to take the Challenge!
Journal/Biography of the Week: Satellite TV 101 by Ann Devereaux
Web site(s) of the Week: EDC's PTK Evaluation site
How to Subscribe
***
LIVE FROM THE RAINFOREST: still interactive after all these months...
We quoted Paul Simon's song about "lasers in the jungle" during program 3,
and we're thinking of Simon again in reminding you that even though we're
not "still crazy after all these years" we are at least still interactive,
online, through May 30th. "Researcher Q&A" is still accepting questions
through the end of this month, and individual responses may come back from
some of the INPA/Smithsonian researchers on location in Manaus, such as
Claude Gascon, Susan Laurance, Marcelo Lima and/or Mario Cohn-Haft, and
others, many of whom you and your students may have seen during the
programs. We've always found that Q&A becomes most active after the
programs--so it's not too late! Send us too many questions to handle, and
we'll tap more experts!
But before sending new questions, do please check out the existing archive
of "onair" questions already answered during the live programs by experts
from the Smithsonian--you might find the exact information being sought
already available, and we try to preserve valuable expert time for new
questions. It also helps students in formulating new questions to review
what's already been shared. (That's online at INTERACT, "onair")
And as teachers and students think of the end of the school year, we hope
you'll post examples of student work online (INTERACT--"Classroom
Connection") and share summative comments with PTK and our evaluation team:
we always try to learn from each project, and make the next one "more
better". Please see EDUCATORS "Evaluation" for information about how to
submit comments.
And thinking ahead--how do LIVE FROM THE SUN... LIVE FROM THE ARCTIC... LIVE
FROM THE EDGE OF THE UNIVERSE... LIVE FROM THE HEART OF THE ATOM... LIVE
FROM THE EYE OF THE STORM... sound? They're all on the list for future PTK
projects over the next several years, and we hope you'll participate in
these exciting learning adventures.
***
LFRF & LIVE FROM THE POLES re-runs on NASA-TV
Though some of our original live telecasts were pre-empted for space shuttle
events, NASA-TV provides re-runs of all 3 LFRF programs and LIVE FROM THE
POLES during May.
Today, Friday May 8, at 14:00 Eastern, and then several times more at
3-hourly intervals, you can view LFRF program 2, "Worlds Beneath the
Canopy".
May 15 brings LFRF program 3, and May 22, LIVE FROM THE POLES.
(LFRF #1 was once again pre-empted in re-runs, and will be re-scheduled.)
The NASA Television Education File schedule for May is posted on the
internet at Spacelink:
http://spacelink.nasa.gov/NASA.News/NASA.Television.Schedules/Education.Schedule/index.html
(Please note that while that long URL may be broken into multiple lines in
your e-mail message, it is in fact ONE line.)
***
Challenge Questions: check out the Questions and Answers online
Though weekly Challenge Questions are now over, you can find a full archive
online: check out INTERACT, "discuss-lfrf", for the historical record of
Eileen Bendixsen's weekly posting of LFRF questions, answers and winners. We
hope you've both had fun and been informed by these CQ's, and look for more
CQ's next time!
***
Backyard Biodiversity Survey: time to take the Challenge!
April is "the cruelest month", wrote poet T.S. Eliot--and with Easter and
intermittent bad weather, it may not have been a great time to get out
physically in the field (or backyard) and do your survey. We know there were
certainly more classes registered than we've received results. But don't
despair! Even if you've not collected raw data, your students can still
wrestle with mind-teasing challenges related to biodiversity. Go online via
INTERACT, "debate-lfrf" and later today (Friday May 8) you'll see
opportunities for a kind of BBS data "scavenger hunt" using the results that
have already been posted online. There are challenges at a couple of
different levels of difficulty, so students and teachers should find one
that fits!
***
Journal/Biography of the Week: "Satellite TV 101" by Ann Devereaux
If you've checked out TEAMS you'll know that you can find lots of
biographical information there about the folks who appeared on camera during
the live broadcasts. But as this excerpt indicates, there are also some
"Behind the Screens" Journals which tell you how the images got back to the
United States. The Web site adds some images of many steps in the
telecommunications process which Ann refers to: consider this just a sampler...
###
SATELLITE TV 101
So, how do you get live TV from the middle of the Amazon? There are no
cables strung, so it's not as easy as just plugging in a camera. And given
the terrain and distances, there's nowhere high enough to point an antenna
directly toward a reception tower in Manaus--much less to anywhere in the
United States! To cover the distances involved, then, from the rugged area
we'll be working in, the only way to do it is via satellite.
But why satellites? For the answer, just remember the last time you stood on
a high hill, or looked out a window of a tall building. From this high
point, you could see much more of the surrounding area than you could when
you were standing on the ground. Since the Earth's surface is curved like a
ball, the higher that you get, the farther you can see (but never around the
back of the ball, right?) To get the best view possible, you have to get
into orbit--you'll have become a satellite of Earth! Communications
equipment senses electromagnetic rays just as your eye does (though
generally at different wavelengths), and higher is also better for
communications "views", too. And so we put satellites for communications
into orbit.
A satellite link of this type consists of three points: the remote site
(e.g., the Amazon) to which you want to communicate; the local site, where
you have convenient access into a communications infrastructure (e.g., the
U.S. telephone network) and your audience; and the satellite itself.
The basic idea of the satellite is that it's a relay; it serves as a bridge
between two existing data networks, allowing voice, video or information
bits to flow between them. For example, telecommunications satellites bridge
the Atlantic Ocean between the U.S. and European telephone networks,
allowing phone calls from local exchanges to be routed overseas into
international calls. In our case, though, our Amazon "data network" only
consisted of some phone and TV ports in our satellite terminal room, hardly
comparable to your local phone company!
The ground parts of this satellite link are "earth stations", are the
jumping off points for the signals to and from space. An example of an earth
station is an ordinary satellite TV dish, which receives television signals
from special purpose satellites. At some central location would be the other
side of this link, another earth station, from which the television
distribution company is sending up the music, movie, and sports channels
which the satellite bounces back down to the home earth stations. This is a
specialized kind of link called a "point-to-multipoint" broadcast, where
only a single earth station talks while many others listen.
Though we are also doing television with our earth station, we will be
operating "point-to-point", which is to say, we will be connected directly
to one single other earth station. Another difference will be that we will
be both sending AND receiving signals. Like the television distribution
company, we'll be transmitting video and audio, in this case ultimately to
Mississippi State University, but we'll also be receiving audio and video
back from MSU at the same time to monitor the progress of the show. Along
with the two-way television will be simultaneous two-way voice channels,
which will allow local production workers to talk with and get direction
from the producers and directors at MSU. Both sides of our link have to be
able to talk and listen at the same time.
So, what happens to the real television signal, the one with the great
rainforest pictures, once it leaves the Amazon? Our earth station is
especially designed to work with NASA's Advanced Communications Technologies
Satellite (ACTS), which is in a geostationary orbit above the earth.
"Geostationary" orbit means that the satellite is travelling around the
earth at exactly the same speed the earth itself is spinning, and so, from
the surface of the earth, it appears that the satellite is at a fixed point
in the sky all the time. The satellite is located above the equator, near
the central part of the Western Hemisphere, giving it a good "view" of both
North and South America. Its view of this hemisphere is so good, in fact,
that ACTS has been used to support communications experiments in places as
far apart as Hawaii and Antarctica!
To contact ACTS, we have set up a large, solid antenna dish, about the size
of a backyard TV dish. The dish is mounted on a heavy pedestal, and pointed
to the spot in the sky where ACTS sits in orbit, 22,500 miles away. Much
closer by, in an air-conditioned room, there is audio and video equipment
which takes the TV signals from each of the two cameras to be used, along
with the additional phone lines, and compresses and combines all these
signals into a single stream of ones and zeros. The stream of bits is
encoded on to a radio carrier, which is then beamed up to the satellite.
The ACTS satellite is called the "Switchboard in the Sky." Like a
switchboard, the bits from our earth station are routed to their destination
earth station, which happens to be the main ACTS control center at NASA's
Lewis Research Center in Cleveland, Ohio. But the production facilities for
Live from the Rainforest are located at MSU, which is a few states over and
down from Ohio. No satellite is necessary, though, this time. LeRC is well
connected into the U.S. phone network, as is MSU, and so a high-capacity,
but otherwise ordinary, phone connection is established between the two
sites. Thus video coming from the Amazon is immediately forwarded from
Cleveland to Mississippi through the phone system as soon it is received
from the satellite.
MSU is the control center for the LFRF productions, and so at the same time
it is receiving video from the Amazon, it is also receiving video from the
various classrooms around the country which will be participating in the
show, as well as from the Smithsonian Institution and NASA's Classroom of
the Future in West Virginia, TV stations like WGCU in Florida, and schools
such as Union Middle, in Dysart, Iowa, and Millbrook, NY. Which is not to
mention the live MSU studio segments with Camile McCue, the host of the
program. Far-flung video feeds, graphics, tape pieces, host segments all
this has to be knitted together - on the fly!! - to make one, one-hour Live
from the Rainforest broadcast, and everybody needs to be able to talk to
each other during the course of the show. As the live show progresses minute
by minute, the production crew assembles the pieces of a Live from the
Rainforest broadcast, a few minutes from the Amazon, now switch to a tape
piece about spiders, now over to Austin classroom for a question, oh,
trouble with the Austin video, quick-switch back to Amazon camera two... How
does it all work? I have NO idea, it's MUCH more complicated than satellite
engineering!
But it does no one any good if the only people who see the show are the
production crew at Mississippi State. So, the by-now well-traveled signal
has one more trip to make, another satellite tour. Remember the
point-to-multipoint TV example? That's right, this time, the real-live
television program finally gets treated like a real-live television program:
transmitted up to a U.S. commercial communications satellite and then
broadcast down to any earth station-that is, satellite TV dish--that can
point and tune in to it. These dishes (not quite the same as home TV
receivers) are located in classrooms, universities, natural history museums,
NASA centers, and even other television stations, which can further
distribute the signal over their own TV broadcast antennas or cable systems.
Oh, and there will be at least one more round-trip, back to the Amazon! One
of the uplinks will be to an international communications satellite, which
also services both North and South America. This allows the show, from the
Amazon, via Mississippi, to also be carried back throughout Brazil, live,
over the Brazilian television station, TV Cultura, Sao Paulo. Back here in
the rainforest, then, not more than a few feet from our scientist guests
answering questions live on camera, will be a small satellite TV dish tuned
to TV Cultura, and "Live from the Rainforest." Dubbed into Portuguese, of
course!
So now, when you're sitting at home or in class, watching the Live from the
Rainforest programs on your TV with its cable connection or even
old-fashioned rabbit-ears antenna, think about how easy it is to just be
able to use the TV remote control!
For more information on NASA's ACTS program, check out their home page at
http://kronos.lerc.nasa.gov
***
Web site(s) of the Week: EDC's PTK Evaluation site
While this section of the weekly Updates has pointed to many excellent
resources beyond our own PASSPORT TO KNOWLEDGE site, this time--as we think
about wrapping up the project--we'd like to encourage you once more to visit
the resources hosted by EDC, (the Center for Children and Technology of the
Education Development Corporation), PTK's external evaluator. This site
provides a place for you to check out responses to previous PTK projects, a
special mail list to share evaluation concerns and ideas, and links to sites
providing information about national, state and local standards and
assessment protocols. Obviously we all hope you and your students found LIVE
FROM RAINFOREST exciting and useful. EDC's site is a way for you to let us
know what worked--or didn't!
You can link in via INTERACT, "Evaluation", or go directly to:
http://www.edc.org/CCT/ptk/ea
***
How to Subscribe to LFRF Online Resources
In addition to these weekly UPDATES, PTK also offers a set of mail lists, or
online discussion groups via e-mail, for educators and others planning to
use the project, which allows teachers to share ideas and successes, ask
questions, discuss problems, make suggestions, etc.
The easiest way to subscribe or unsubscribe to either DISCUSS-LFRF,
DEBATE-LFRF or UPDATES-LFRF is to visit the INTERACT section of the LFRF web
site at:
http://passporttoknowledge.com/rainforest
and complete the simple registration and subscription form found there.
INTERACT also provides a full archive of all previous postings to the lists.
We hope you'll continue to use UPDATES through the end of May to keep
abreast of PTK news, DEBATE to join in the final phases of the Backyard
Biodiversity Survey, and DISCUSS to let the PTK team and your colleagues
know what's on your mind, and to make suggestions about how to ensure LIVE
FROM programs are exciting and worthwhile learning adventures.
Onward and Upward,
Janet K. Cook
Editor, UPDATES-LFRF
&
Geoff Haines-Stiles
Project Director, PASSPORT TO KNOWLEDGE
