On Wed, Apr 9, 2008 at 6:14 AM, Steven M. Bellovin <smb@cs.columbia.edu> wrote:
On Tue, 08 Apr 2008 22:16:57 -0700 Joel Jaeggli <joelja@bogus.com> wrote:
Patrick Giagnocavo wrote:
Sean Donelan wrote:
Awesome, so could anyone buy a copy of the same images? Which satellite do you think happened to be taking images of the area with these ships near the time the cables were broken? Which company is selling that set of images?
Wouldn't it be reasonable that, when the break occurred, they used their optical time domain reflectometer to compute the approximate location of the break, and then just called around for whoever had the best images, or who could quickly task the satellite to get an image?
spot can generally deliver an image within 1 day in 60kmx60km blocks assuming no contention for the slot. 20m resolution is more than adequate to pick up ships underway at sea. ikonos can deliver 11x11km swaths.
Right, but those images would be after the fact.
Assume the ship is moving at 10 knots, which is 18.5 km/hr. In 24 hours, it can go about 450 km. You can't go south from Alexandria by ship, except into the Suez canal, but you can go about that far east (eyeballing Google Maps...) before you reach Israel or Israeli-controlled waters. A semicircle of that radius has an area of about 320,000 km^2. You'd need about 100 images (88 by sheer area, but you won't get an exact match); the pictures alone would cost a minium of $100K, according to http://www.spotimage.fr/automne_modules_files/standard/public/p425_ba582c667... and quite possibly considerably more. *Plus* there are a lot of ships to consider -- that area includes the northern terminus of the Suez Canal, and you want good enough evidence to take to a maritime court somewhere.
It might be possible.
There are a number of unique characteristics of ships including profile and radar fingerprint. I'd like to see the images from the article that was forwarded to the list. -M<