Flow, t thint jst rainwater, ia toxic mix raw sewage from neighboring tiajuana, draining into Southern California on lower ground, eventually emptying into the pacific ocean. So it effectively its like a toilet flushing straight into ticking has anyone ever brought back something from mars . No. It will be the first roundtrip adventure to any other planet. Four previous mars rovers have paved the way for this mission. The last rover, named curiosity, has been exploring and sending back images like this for eight years, but perseverance is the first rover that will be able to look for evidence of ancient life and collect samples that nasa plans to bring back to earth. That does not sound possible. ticking im lesley stahl. Im Bill Whitaker. Im Anderson Cooper. Im sharyn alfonsi. Im scott pelley. Those stories, tonight, on 60 minutes. ticking this portion of 60 minutes is sponsored by progressive insurance. Save when you bundle auto, home, or motorcycle insurance. Visit progressive. Com.