Thread Subject:

finding the gravitational point in a vector field

Hi,
If an alien visits the earth, he will find that everyday millions of
people around the world face towards a point, several times a day and
perfom some rituals. The alien does not have the resources to draw a
line from each individual and find the intersection point of them all.
How does he go about finding the common point, using only the way
their faces point to (the vectors in the vector field)?
Is there a fast way? To be more specific, I have an area with tens or
hundreds of vectors (starting from the location of sensors pointing to
the unknown common point). I know the slopes of the lines (in a
cartesian system) parallel to each vector. I put a grid on the area,
find the intersections and count how many lines intersect within each
grid cell. Assign a colormap and the image tells me of possible
sources of signals But, the picture changes every 10 seconds with new
vectors, and finding the line intersections takes time. Given the
slopes and the coordinate system of the field, can I find the solution
in a faster way?

Thanks in advance,
Kamran