that works for navigation purposes. it's highly unlikely that the gps satellites were changed in this scenario because now there's enough satellites in the air that that's reliable and it's a certified way of navigating. i don't think that has to do with that. however, with navigating off the cell phones if they're still active, which is very confusing to me as to why they would still be active at that point and why they would be able to ring them so i really don't have an answer for that. i'm no expert in that area, but i would think that that would be possible, certainly. >> it is entirely by zarl altogether. david sous si, thank you so much as an expert in this field. chris, to you. brooke, we have breaking news in the ukrainian peninsula of crimea. we hear that a skirmish has been breaking out on and off between russian forces and ukrainian soldiers at a military base. let's get to nick payton walsh. he is in this nation in the western part of crimea.