[medved]

You don't find fractal topography like that on rivers and you don't find 5000-kilometer rivers on Mars, Earth, or anywhere else that I know of.

How would a 5000-kilometer river work? Where would it flow from? Where would it flow to? How would you get a constant downward flow of water for 5000 kilometers, or would the water flow downhill in some places and uphill in others?

[Doctor Stochastic]

... you don't find 5000-kilometer rivers on Mars, Earth, or anywhere else that I know of.

Well, the Nile, the Yangtze, and the Amazon are all longer than 6000 kilometers. The Rio Bravo del Norte (outside my back door) is over 3000 kilometers long.

[Junior]

The Nile and Amazon are at least 5000 km long -- that's only 3000 miles.

[jimt]

You don't find fractal topography like that on rivers and you don't find 5000-kilometer rivers on Mars, Earth, or anywhere else that I know of.

Try this site.

http://www.rev.net/~aloe/river/

It lists the Nile as 6484 kilometers to the surce of the farthest tributary.

Perhaps a little more research before postulating electrical arc craters?