rehab in houston that i was able to rejoin my crew and complete this mission. certainly no regrets. there are periods of time over the last 16 days that, you know, you miss your wife and your kids and i think that's true for all of us. but in hindsight, it was absolutely the right decision. we got all of our mission objectives done. we did four very challenging spacewalks. we got the ams installed and another pay load on the outside of the station so for me it was certainly the right decision. >> gentlemen, thanks for your time. have a wonderful final moments to your journey. we'll see you back on earth. >> you're welcome, john. i have to say that was pretty cool. i'm on the cnn express. that's late last night in gettysburg, pennsylvania talking to the crew up in space. nice how technology works in our favor sometimes. when we come back though questions about technology. a new study says you should be worried that your cell phone could cause brain cancer. we'll explore that just ahead. ♪