Steve Fossett

We can take pictures of objects on the Earth from space that
are 2 inch's wide. We can take pictures of objects on Mars
that are 12 inches wide. Why can't we find a wrecked
airplane in Nevada?? A place that is mostly dirt and sand
with very little vegetation?

Makes no sense

On Sun, 09 Sep 2007 10:36:35 -0400, NoneYa wrote:

We can take pictures of objects on the Earth from space that
are 2 inch's wide. We can take pictures of objects on Mars
that are 12 inches wide. Why can't we find a wrecked
airplane in Nevada?? A place that is mostly dirt and sand
with very little vegetation?

Makes no sense

No, you just have to understand the realities of the process.

Imagine a satellite snaps a picture of Wittman Field during Airventure. Assume
it has a high enough resolution to allow individuals to be recognized. There
are 400,000 people on the grounds at the time...and you want to find one
particular person. You don't know where he was at the time the photo was taken

That means you will have to zoom in on, individually, each person visible on the
image. With average luck, you'll have to examine 200,000 individuals before you
find your friend.

(Heck, here's an aerial photo of Oshkosh:

http://www.airventure.org/2007/media...al_from_SW.JPG

....just try to COUNT how many people are visible)

Keep in mind, too, that this isn't a mug shot...unless they were pre-warned, the
people in the image won't be looking at the camera. If you take the picture
from directly overhead, all you see it a bunch of caps. But even if the picture
was taken obliquely, some folks will be turned away from the camera, or holding
a cup to their mouths, blocked by other people, inside the exhibition halls, or
using a portajohn, or lying under a tree, or even unexpectedly off the grounds
entirely.

The problem is analogous to the Fossett search. Let's assume the camera gives
the equivalent of viewing an area 500 feet by 500 feet. That is about .01
square mile. With a 10,000 square mile search area, that gives one million
500x500 foot blocks to examine.

And remember all those persons who were turned away or kneeling down, tieing
their shoes, in the Oshkosh picture? After nearly two weeks of an intense air
search, the lack of success is probably because Fossett's Decathlon doesn't
strongly resemble an aircraft any more. It's undoubtedly crumpled, it's quite
possibly burned. By now, it's probably dusted with the "dirt and sand" you
refer to, making it blend in even better.

The persons who would examine the imagery wouldn't be looking for the big white
"+" of wings and fuselage, they'd be looking at every apparent bush, every
apparent rock, to guess if sometime, in the past, it just may have been an
airplane. How long should they examine each block? If each takes two minutes,
we're talking well over 30,000 labor hours. Every shadow on the image might
hide wreckage, so you'd better have another set of photos taken at a different
time of day. AND look at those.

Finally, finding hidden objects in imagery is a *military* specialty your
typical Ikonos analyst doesn't practice. If you want experts to look for the
plane, you're going to have to go to the government...and those folks are pretty
busy on some pretty important tasks.

Ron Wanttaja

Ron Wanttaja wrote:


No, you just have to understand the realities of the process.


That's a bad analogy, we're not looking for one airplane in a sea of
other planes. Remove all the planes in the picture except one. Now try
and find the one plane.

"Newps" wrote in message
...


Ron Wanttaja wrote:


No, you just have to understand the realities of the process.


That's a bad analogy, we're not looking for one airplane in a sea of other
planes. Remove all the planes in the picture except one. Now try and
find the one plane.

Except that Fossett's plane may or may not look like an airplane now. Or it
may
be partially or wholly obscured by vegitation, water or shadows.
Or both.
TP

Makes no sense

Or he landed on a whitish lake bed, flipped over and you are trying to
find a whitish underbelly on top of white dirt. I keep watching news
hoping that he will have been found alive but those hopes are fading.

Ron Lee

On Sep 9, 9:36 am, NoneYa wrote:
We can take pictures of objects on the Earth from space that
are 2 inch's wide. We can take pictures of objects on Mars
Why can't we find a wrecked
airplane in Nevada??

they are doing so.

still a ton of data for the computers to churn through.

why not take some computer programming courses to see why such things
are difficult.

a starter course on photography can also give you some clues.

on the other hand, he could have drilled in so hard that there may
only be a patch of dirt slightly darker than the surrounding dirt.

On Sun, 09 Sep 2007 10:20:40 -0600, Newps wrote:

Ron Wanttaja wrote:

No, you just have to understand the realities of the process.

That's a bad analogy, we're not looking for one airplane in a sea of
other planes. Remove all the planes in the picture except one. Now try
and find the one plane.

As I originally posted,"After nearly two weeks of an intense air search, the
lack of success is probably because Fossett's Decathlon doesn't strongly
resemble an aircraft any more. It's undoubtedly crumpled, it's quite possibly
burned. By now, it's probably dusted with the "dirt and sand" you refer to,
making it blend in even better....The persons who would examine the imagery
wouldn't be looking for the big white "+" of wings and fuselage, they'd be
looking at every apparent bush, every apparent rock, to guess if sometime, in
the past, it just may have been an airplane."

Just because a section of the image DOESN'T contain a *recognizable* aircraft
doesn't mean the wreckage of Fossett's plane isn't there. You could certainly
shorten your search time if you only searched for intact airplanes that were not
covered with dust. But I don't believe the Decathlon is just sitting parked,
undamaged.

Here's a picture of a Twin Beech crashed in the desert:

http://www.aircraftwrecks.com/images...beachcraft.jpg

Noticed how the crumpled portion of the main section seems to blend into the
desert. The tail cone is fairly obvious (this close), but remember the
Decathlon was fabric covered...it may have burned away, and all they'll see is s
skein of blackened 3/4" steel tubes. It probably looks closer to this:

http://www.ctie.monash.edu.au/hargra...desert_500.jpg

It's been two weeks. Certainly one doesn't want to give up hope; after all, an
elderly woman lost for two weeks in the Pacific Northwest was recently found
alive. But then, she was in the woodlands, not a desert. How much water was
Fossett carrying?

Ron Wanttaja

On Sun, 09 Sep 2007 19:52:30 +0200, Martin wrote:

On Sun, 09 Sep 2007 10:20:40 -0600, Newps wrote:


No, you just have to understand the realities of the process.

That's a bad analogy, we're not looking for one airplane in a sea of
other planes. Remove all the planes in the picture except one. Now try
and find the one plane.

and use software to compare old images with new ones to identify changes.

You'd have to have before and after photos with matching positions and view
angles of the satellites/aircraft or the photos you're comparing will be taken
from two different angles. You'd have to have the "before" photo taken at about
the same time of day and the same time of year, since the shapes of all the
shadows will be different, otherwise.

Finding a "before" picture might be a bit challenging. After all, it's
desert...how often is someone going to shoot a high-resolution picture of it?
The older the "before" picture is, the more natural changes will have occurred
and the more false positives. You'll have to hope no bushes have died off since
the previous photos were taken, that no new ones have grown, that the wind
hasn't pushed any dunes around, that no four-wheel-drive enthusiasts have cut
new tire tracks, etc. etc. etc. Having to chase down ~50,000 false positives
might slow things down a bit.

I'm a space (spacy?) guy, not a computer sciences type, but it seems to me that
the processing capability needed will be stretching the current technology.
Let's assume you've got a ground resolution of 3 feet. That's ~1760 pixels per
linear mile, 176,000 pixels per single row, or about 30 gigapixels total. Give
it a lousy 256-bit color, and that's about a 7.6 terabit image. Excuse me, TWO
7.6 terabit images, since we'll be comparing them.

Sure, the US Government might have the capability...but they'd be comparing
photos taken with same camera, taken just days or weeks apart, from the same
orbit, at the same time of day, etc. In any case, they are not likely to let a
set of civilians waltz in and borrow their computers.

Ron Wanttaja

Newps,

That's a bad analogy, we're not looking for one airplane in a sea of
other planes. Remove all the planes in the picture except one. Now try
and find the one plane.


Hey, "we" can't even find Osama when "we" have 6 years to try (in a similar
landscape, I might add).

--
Thomas Borchert (EDDH)

Ron,

Finding a "before" picture might be a bit challenging. After all, it's
desert...how often is someone going to shoot a high-resolution picture of it?


Well, FWIW, it's a part of desert that (I was told) contains one of the largest
ammo storage facilities in the world. So it might just be photographed a little
bit more often. That said, I still think you're absolutely right about the
chances of finding it.

--
Thomas Borchert (EDDH)