(orchestral music)
- [Voiceover] As you'rewatching Old Faithful
for the last few minutesbefore an eruption,
we would like to tell youa bit about this video.
A small group of scientists
from the CaliforniaInstitute of Technology,
Arizona State University,
and Yellowstone National Park,
have been studying how OldFaithful works in detail.
We are especially interested in geysers
since they seem to work invery similar ways to volcanoes
like Mount St. Helens,
yet we can safely workaround Old Faithful.
Some time ago,
we made measurements oftemperature and pressure
at several depths downthe vent of Old Faithful.
We collected data starting fromthe time that it emptied out
at the end of an eruptionuntil it refilled
and finally erupted again.
From this work we learned manydetails of how geysers work,
but of course we stillhave many questions.
We'd like to know wherethe water comes from.
Does it come from the sides,or from the bottom, or both?
Why does it stop filling up atabout 15 feet below the top?
If you look down from the top,
the vent is a slot aboutfour or five feet long
and about a foot wide.
You can see down about 10 feet.
But below that,
we really don't have anyidea what the vent looks like
or what effect its shape may have
on the way Old Faithful erupts.
We wonder if the ventfills with water quietly,
or if it is boiling.
Old Faithful also makesa series of big splashes
before each eruption.
You have been seeing these in the video.
In fact, an especially large one
usually triggers off the eruption.
We don't really understandwhat that's all about.
These and many otherquestions have lead us
to want to see what's down there.
Just recently, it's been possible
to get a very small television camera.
We have put one of these cameras
in a metal housing to protectit from the boiling water,
and to keep it cool.
With it we have been taking video pictures
down into the throat of Old Faithful.
We thought you might like to see 'em.
As Old Faithful again throwsa big bunch of water out,
this time it probably isgoing to start the eruption.
And indeed that's the case.
There is Old Faithful in full eruption.
Here you see that OldFaithful's surface vent
is a slot-like structureas I mentioned before.
It's covered with amaterial called sinter,
which looks like of like snow,
but it's actually made out of silica,
a very hard material that coats everything
that gets splashed with erupted water.
The housing we built for thecamera is seen in this view.
It's a stainless steel Thermos bottle
with the camera on theinside cooled with ice.
It's attached to thesurface by a long cable.
You can see the white onefoot markers on the cable.
Here we are testing the lightsneeded to take video pictures
down the dark vent.
Here is the little cameraitself out of the housing.
It's about two inches long
and about three quartersof an inch in diameter,
lens and all.
We now have the camera downinto the vent of Old Faithful.
It's about six feet down
and it's swinging on the endof its cable at the moment
and we will soon be on our way down to,
as deep as we can get safely.
At this moment,
we're still discussing exactly whether
all of the hardware is working
and if we have the cameraproperly hooked up electrically
and the right microphones running
and all those sorts of things.
And we want to make surewe've done everything right
before we go in because we have no idea
what's going to happen.
You can see the near wall of the vent
in the bottom left corner of the picture.
The top right hand is insunshine and it's overexposed.
And here we go down the vent.
And you can see it's still a slot,
down as far as we can see so far,
it's really quite a narrow slot,
just a few inches wide.
You also see occasionallydrops of water falling down.
You'll see those as we go along.
That's water that's condensingfrom the steam in the vent
on our cool housing.
Those drops are very convenient actually,
because they tell us whichway is straight down,
which we otherwise wouldn't know
and we didn't really plan it like that
but that's the way it worked out,
which was very convenient.
We're dragging most of the timealong the side of the wall.
Notice at this point wecan see some fractures
and cracks in the side walls,
although the side wallsactually look very smooth
and that's because they'recovered with the sinter material
that we see up on the surface.
Notice now that there's lots of water
coming from down below.
It's very tiny,
uh, little dropletsthat are being blown up
with the steam that'scoming up from below us.
And now you can see
we seem to be coming to akind of a shelf-life structure
and we worry about whetherwe're going to land on that
and not get off of it.
And we bang into the surface of it
and kind of bang up and down a little
and how we go over theedge which is very nice.
But here is yet another one
and this time you can seea pool of water down there
and because of the droplets,
we know that we're gonnaland just to the side
of that little pool of water.
There seems now to be a lotof water coming down around us
from the sides which is notcoming from our housing.
Now we're landing on thisflat little platform of rock,
and banging up and down.
And the folks handlingthe cable at the top
now think that they're OK,
but actually the camera islaying there on that shelf
and the cable is just goingon down the hole below it.
Now since we can see it,
why we can tell them that that's the case,
and so they will startbringing the cable back up now
to pick up the cameraand see if we're lucky
and can get over the edgeof this ledge somehow.
We've known about this ledgefrom our measurements before,
and always wondered what it might be.
In fact, we thought it was probably
a narrow place in the slot,
but in the picture as we werecoming down a moment ago,
you could see that it reallywas just a flat shelf.
So we have some good chance
that we'll be able to work our way
over the edge of it somehow.
So at the moment you seelots of water by the way
moving down around the camera.
Aha! Here we come off of the ledge
and we're banging around again,
and now it looks as thoughwe've gone over the edge.
So we've been luckyand got past this ledge
and we're down into amuch bigger open area now.
You can't really even seethe far side wall quite yet.
And now suddenly we seesomething very striking,
which is, was a big mystery to us
as we were watching this in real time.
It's clearly just wildly boilingwater which is boiling up
and splashing all over the camera.
We had not really intendedthis camera to be in,
submerged in the water
and so we were quite concerned about this
and we actually stopped at this point
and came back up alittle bit to think about
what we were seeing andwatch it a little more,
and we did realize at that point
that what we were seeing wasthis wildly boiling water.
But we really didn't thinkthat was a good thing
to put the camera down in,
so we decided that wewouldn't go down any further,
that we would start back up
and we would go up somewhat slower
so that we could see inmore detail what was,
we were going by and whatthe walls of the vent
really look like and see ifwe could see water coming in
from the side and other things like that
that we were interested in.
Also, this would allow us to measure uh,
the dimensions of the vent
because we had calibratedthe camera in the laboratory
so we could actually makemeasurements of sizes of things.
Here you see us going back up
this kind of the side of that platform
that we landed on a bit ago.
We're actually going upabout a foot at a time,
waiting for a few seconds
so we'll have a chanceto see things pretty well
and then going up another foot.
Now you can see our puddle of water again
and see where we actually landed
from the drops of water from our camera.
We see large amounts of...
these uh, drops of water coming in
seemingly all directions.
Not only from the bottom but also seems
that we seem to see somecoming from the sides.
As we move up,
we occasionally come out into an open area
and we swing as we are doing now,
and that gives us a view
of a little wider area
than when we're dragging alongthe side walls of the vent.
You can see that the uh...
The picture sometimesgets a little fainter.
That's because we had to adjust the lights
as we went up and down
and of course when wegot close to the wall,
then we had to turn the lights down
to keep from overexposing the video.
And then as we got outinto a big open areas,
we had to turn 'em on more intensely,
we uh, didn't do that very perfectly.
Notice by the way,
in the bottom right handcorner you can see a waterfall
uh, falling down the side.
Seems to be coming from kindain underneath this slot.
It's not very much water,
so we don't think that that'sa major source of the water
that's filling the uh, the vent.
Now we're back up into reallyquite a fairly narrow slot
and uh, we seem to have gotten up above
so much splashing and um, other things.
Now occasionally asjust then, you see fog.
That's because the windis gradually getting
a little higher up at the top
and it's blowing down into the vent
and that allows fog to form
as it cools the steam in the vent.
And you will see thatoccasionally as we go along
when a gust of wind um...
causes some uh, some airto get down in the vent.
The vent is full only of steam, normally
and the steam is quite clear fortunately,
otherwise we wouldn't be able to see much
because everything is at theboiling temperature of water
so you don't get a fog of steam
as you do out of a chimneyor something like that.
Big blast of water right then,
coming from down below,
continuing at some level here.
It gets onto the window of the camera
uh, and makes the image a little uh...
a little bit fuzzy.
There's another blast of air.
We've stopped now.
We're about 11 feet and we've stopped now
to decide what we're going to do,
whether we're going togive up at this point
thinking that we're luckyand we didn't bust our camera
or decide whether we want to get brave
and go back down again
and see now that we understandbetter what's going on,
see a little more details about that.
And um, so we decide infact to go back down again.
We have an awful lot of nice video there
and if somehow we do thecamera in in this process,
well we uh, we tried.
(laughing)
And we'd have a lot ofinformation that will keep us busy
for quite some time.
So now that we kinda know what to expect,
we'll see and recognize things better
than we did the first time down.
Notice how very smooth the walls are uh,
that's the sinter coating everything.
There's our waterfall again, uh,
really quite striking in theright hand side of the picture.
But really there's not verymuch water in that and uh,
you can see there are littlepuddles of water all over
that shine in the lights andnow we can already see the uh,
the top of the boiling water.
It's coming very muchhigher up into the vent
than it was when we weredown just a few minutes ago.
We've come to our little shelf again.
(laughing)
And the first of the little shelves,
and we bang around on it again and uh,
we manage to get by it.
Notice though that there's lots of uh,
water boiling around.
It's turning the camera around.
There's our shelf wherewe got stuck last time
and we have to worry about
whether we're gonna get stuck again.
And uh, sure enough we do.
The camera's now not moving,
but then suddenly something happens uh,
probably a big uh, splash ofwater from the wild boiling
and it kind of knocks us off of the shelf
and now we've gone downa little ways and uh,
we really are seeingthe wildly boiling water
and water pouring aroundus in all directions
and looks like a tornado now and again
as it twists the camera,
spins the camera aroundon the end of its cable.
We really became very concerned
whether our camera was goingto survive all of this.
It certainly wasn'tmade with that in mind.
Never had any idea thatwe were gonna be involved
in anything so wild as this.
Notice the big blast of water
from the side wall at that time.
That was a lot of water,
but it was just a sudden burst,
so we don't really know whether that's uh,
one of the sources of water for filling it
that somehow doesn't run in a steady way,
or whether it's just waterthat splashed over the edge
and kind of off to the sideand is now running back in.
We're coming back up again slowly uh,
coming up a foot andwaiting two or three seconds
and then another footand every once in a while
we get just completelydrowned in water and foam
and uh, you can't see anything at all.
We're coming up againnow on the little shelf,
and notice how much water'srunning down the side of it now.
Clearly just from thesplashing of the water
and the wild boiling.
Things really are getting very much wilder
um, as we are down there this time.
The vent is clearly filling up with water.
We're still about 20 or 25 minutes
before the next eruption,
so we're not concerned that we're going to
suddenly get caught in an eruption,
which I'm sure thecamera would not survive.
So what have we learned?
We didn't see an obviouslarge source of water,
so we think it must be comingfrom below 40 feet somewhere.
We also saw no sidechannel that would explain
why the vent doesn'tfull up above 15 feet.
We'll need to watch what happens
when the water levelactually reaches that depth
to understand what'shappening there, I think.
We saw that the vent continues as a slot
down to about 35 feet and thenopens up to a bigger shape
and that helps us understand somewhat
how the eruption works.
We found that the fillingprocess is certainly not
a calm activity.
And we now understand thepre-erupts and splashes
are just the top of thewildly boiling water
as it nears the surface.
Clearly there's much to be learned
using this down hole camera.
We hope you enjoyed lookingdown into Old Faithful with us,
and we'd like to thank the folks
from the Yellowstone National Park
for permission to put ourcamera in Old Faithful
and for assistance in doing so.
(orchestral music)