
Why ghostly false positives cropped up in MH370 satellite hunt - adenner
http://www.wired.co.uk/news/archive/2014-03/26/ghostly-plane-images-mh370-satellite-hunt
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tgb
Math doesn't check out for me: plane flies at ~700mph or 0.2 miles per second.
Satellite speed is on the order of 5 miles per second. Sensors separation is
on the order of a few inches. It would take about 15 microseconds between
first and last sensor passing over the same spot. The plane can only move
around 5 millimeters in this amount of time. It looks like it's moved several
hundred feet.

What am I missing?

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aspanu
I believe that what you are missing is the distance between the satellite and
the plane. planes are at ~10,000 m altitude, GPS flies at 20,000,000 m
altitude. A very small angle of distortion creates a very large distance at
the plane.

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zizzer
Just a note - It's not GPS satellites taking the pictures. It seems to be the
RapidEye [1] satellites, which are much closer to earth at 630km.

[1]
[http://en.wikipedia.org/wiki/RapidEye](http://en.wikipedia.org/wiki/RapidEye)

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yaur
Since there shouldn't be too much moving around the open ocean besides planes,
couldn't you use this artifact to build a semidecent search algorithim rather
than going through all the data by hand?

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afreak
In addition to planes and boats, "islands" of garbage also exist and they
range from the size of small cars to that of small cities.

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yaur
This particular type artifact is created because the plane is bright and
moving FAST enough that it isn't in the same position relative to the sensor
from the beginning of the image to the end. My best guess is that you need
something moving at least 100MPH to see this effect at all and the position of
the double image (assuming the same sensor) should be a function of the speed
of the object. Islands of garbage moving fast enough to be mistaken for a
plane are probably interesting in their own right.

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yaur
As it turns out that the real problem here is that the all of the data from
the 8th is in a pretty useless spot given what we know now. So what is useful
to find is wreckage not planes. After looking at the data I'm also unconvinced
that speed has anything to do with it and that the more likely cause is
altitude.

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malandrew
Thus far, have we found even a single piece of debris that we know came from
the MH370?

I just don't buy the idea that the plane ended up as far south as it did and I
haven't really read of any solid evidence to support this other than one
blurry satellite image with a large but unidentifiable object. If that object
was in fact part of the plane, I have yet to hear of any explanation as to why
the plane was that far south of it's last known position instead of continuing
north west.

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gamblor956
It's a multitude of satellite images, combined with a Doppler analysis of
satellite pings of the aircraft, plus a fuel-range analysis, plus a radar
analysis of the northern half of the potential travel routes...

 _I have yet to hear of any explanation as to why the plane was that far south
of it 's last known position instead of continuing north west._

No one knows that, yet (possibly ever). But they do know that the plane did
not travel north west, as it didn't show up on the civilian or military radars
of multiple countries.

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malandrew
Do we have any good theories explaining why the plane would have even traveled
in that direction? AFAICT there is nothing in that direction on the map. What
were they flying towards?

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throwwit
Out of all the news coverage showing the search crews manning the planes,
never once did I see anyone wearing sunglasses. Wouldn't polarized glasses
actually help with reflection/glare?

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mannykannot
Polarized glasses help with reflection at a shallow angle, but the observers
will be looking down, not across the surface, and when the sun is low on the
horizon, all observers will be looking away from the sun, as it would be a
waste of time to try to see anything up-sun, even with polarized glasses.

In addition, using polarized glasses might lead to seeing the colored bands of
stress birefringence in the window, depending on what material it is made of.

