EVA Duration: The EVA lasted 5 hours 15 minutes.

Crew:

Nick Hall-Patch (EVA Team Leader/Communications Engineer)
Melinda Capes (Biologist)
Mike Kretsch (Health and Safety Officer)

EVA Goals:

1. To visit Candor Chasma and attempt to locate at least four RST sample sites using data from Crew 11
2. To use the amateur radio repeater on Mt. Ellen as a backup means of communication back to the Hab from the EVA team.

EVA Description: Gus Scheerbaum and Shannon Rupert provided HABCOM services. This was an ATV EVA. Our pre-EVA prep time has now been reduced to 20 minutes, at least for two of the EVA crew as a third had other duties in the Hab for a few more minutes. The two left the airlock at 11:03 MST, and got the ATVs started and the soggy tire on the "green" ATV pumped up while third member got ready for leaving the Hab.

The EVA team left the Hab at 11:30 MST, heading north on Lowell Highway, and easily managed to miss the turn-off to Candor Chasma. Retracing our steps, and using our GPS, we found the turn-off more easily by approaching it from the north. A number of the side roads in the area seem to be washed out next to the main road, and only become visible further away. We recorded a waypoint at the turn-off, and built a small rock cairn near the side of the road for future visitors.

The road led to a high point which allowed us to spot another road running down a valley in the general direction of our sample sites, according to the GPS. This road was fairly easily entered a few hundred meters down the main road. We continued to use the GPS to guide us, but again had to retrace our steps when the promising looking road headed off in the wrong direction. We then parked the ATVs and set off on foot for the Sample Site 13 using the GPS for guidance. Our confidence in the coordinates given to us plummeted when the waypoint for Site 13 turned out to be on a plain of scrubby vegetation about 15 m from the edge of the Chasma.

We had been given a site photograph of a gnarled tree, so we found our way down into the Chasma, and within a few minutes found the tree and the first sample site. The Science Report describes our adventures over a couple more hours in finding Site 14, and approximations of Sites 11 and 12. None of them corresponded well with the GPS coordinates we had been given, but their relative separations seemed to be accurate. New waypoints were generated at the various sites, as well as at a nearby Office of General Land Survey marker. Photographs and descriptions of the sites were also created.

While two crew members documented Site 13, the third (a licensed radio amateur) moved somewhat higher up the Chasma and was able to key up the amateur radio repeater using a handheld radio, and quickly made contact with another Crew 21 amateur operator who was using the VHF transceiver at the HAB.

After a quick discussion concerning crew members' bladder capacities, it was decided to return to the HAB, this time with no false turns, and taking a couple more waypoints along the way. We reentered the Hab airlock just before 16:30 MST.

Waypoints: 10 new waypoints were defined, and we used one waypoint defined previously.

Samples: Five rock samples were obtained, one each at the four sample sites, and another from the rock face further down the Chasma.

Lessons Learned:

1. Finding sample sites defined by other groups is not easy. Scales for photographs of sites and samples would make the job easier, as would photographs further back from the site to assist in its identification.
   
   
2. The discrepancies found between the GPS coordinates we were given for the sample sites from those which we observed need to be investigated. Is it possible different datum were used?
   
   
3. If licensed radio amateurs are on a crew, and the appropriate equipment is available, then the amateur radio repeater on Mt. Ellen can be used as back-up communications to the Hab GMRS radios.