Its an optical illusion (these types of pictures seem to be published every month) Here is the actual story: http://www.sky.com/skynews/picture_gallery/picture_gallery/0,,70141-1210748-1,00.html They were well past the 3 miles required by safety
If you know how large each of those planes is, you could probably figure out how close they were to each other. Do we have any science professors here? Aviation experts? Plane enthusiasts?
I was an air traffic controller in the 1970s, and I have about 400 flying hours as a pilot (not flying professionally). As I look at the 6-photo sequence, some things stand out. 1) The smaller jet is clearly below. That probably rules out a "distance perspective" issue. If the two planes were actually farther apart than seems apparent, one would expect the smaller-appearing jet to be on the top. 2) Place yourself in the cockpit of the smaller, lower jet. It is a virtual 100% certainty that the pilot and/or the copilot would see the bigger jet right above and directly in front of them. Every normal piloting instinct would say simply to dive, to go DOWN. But the lower jet continues to cross underneath the clearly visible jet above them, with no sign of them trying to dive. That, to say the least, is very suspicious. That alone leads me to suspect that the photo may be "doctored." Just an opinion.
Required lateral or longitudinal separation is three nautical miles. They are obviously in violation of that. However, required vertical separation is only 1,000 feet. If there is some optical illusion here, they might be OK on that. There are only three ways to attain legal separation of aircraft: (1) lateral, (2) longitudinal, (3) vertical. Any one of the three is sufficient. So if there is some optical distortion here, it is entirely possible that they have the minimum 1,000 feet separation vertically.