We experienced our share of ups and downs today. First thing this morning at 8:00 am, we determined that we needed to change our EVA plan. Mark had planned to finish his drilling experiments with today's EVA but wanted to postpone it for a day or two to feel ready. We needed a new EVA plan.

Fortunately we had already been discussing a return assault on Factory Butte. It did not take long to map out the route. It was the same as the day before except for some small biology sample excursions to be attempted on the way back. The primary goal was the same. The team would probably have enough time to briefly document the sight and take some samples before mission rules required that they begin their return.

I assigned our most capable ATV riders to the EVA, Dave, Elia and Simone and they seemed happy and eager to go. I guess Moby Dick is only required reading in the States.

So as not to waste any of their suit consumables, they roared off to the north immediately after exiting the airlock. A little over an hour later we received a radio call - the team had made it to Factory Butte! They made great time. The route we investigated yesterday, 3 km short of the prize, turned out to be as easy as it looked. Sometimes the shortest distance between two points isn't a straight line.

While the EVA team was experiencing great success, the Hab situation was turning grim. We lost our computer network and Internet access due to a power supply failure in the main computer. Unfortunately our systems guy is not only good with computers, he also knows how to ride an ATV. And he was assigned to today's EVA team.

Usually our daily tasks keep most of us too busy to check our email but somehow it seems one or two crewmembers find time in the afternoon to exploit the Hab's Internet connection - not today. I don't think the crew has ever felt so isolated. Fortunately, after returning from the EVA, Joan was able to set-up the Internet connection on one of the back-up computers. We could reach the outside world again.

But computer problems were not the only challenges we tackled today. The performance of the spacesuit backpacks has been slowly degrading with every EVA over the last few days. And today, Joan finally put one into the grave on the easy, return part of the trip from Factory Butte. At our evening meeting I told the crew that it was time to put some serious effort into making 3 complete packs safe and reliable or EVA's would have to be curtailed. We'll find out how they did in the morning.

There are two valuable lessons to be learned about the simulation from today's events. The first is that crews do not need to fabricate or invent problems to solve. Put 7 people into an isolated tin can for two weeks, surrounded by dust and dirt, and real problems will occur on their own. The ironic thing is that just last night I was discussing with an interested crewmember the possibility of creating a simulated emergency or problem before the end of our rotation. I decided against it. My FMARS experience has made me believe that real, interesting problems present themselves during a simulation all on their own. Today's events reinforced that belief.

The second lesson is that encouraging a crew to follow well defined, detailed simulation constraints produces valuable insights into how manned exploration of Mars might occur. For instance, today's successful trip to the base of Factory Butte was really a culmination of 3 days worth of EVA's.

At the beginning of the week I told the EVA teams to start pushing the EVA's to the edge of the reference mission's safety factors to see what we could do. So on Monday, Dave, Elia and Simone picked interesting biological sample sites that would be challenging to reach under mission constraints. They successfully reached their locations and obtained their samples but they also gained valuable information on navigating through Muddy Creek and Coal Mine Wash, north of the Habitat.

After learning about their knowledge of the terrain, and the relatively easy traverse when on the right path, the trail they blazed seemed to be a promising candidate for routing a team through to Factory Butte. Yesterday we took advantage of the information and made it through the labyrinth of canyons without one wrong turn, to finally arrive at a point where we could see a smooth ride to the beckoning outcrop. Simulation rules made us turn around but by today we had accumulated enough information to guide EVA #11 all the way to Factory Butte in a short amount of time.

I believe this is one model that the first Mars crews might follow when exploring the landscape that surrounds their landing sites. To make it safely to where they will want to go, they will use several EVA's, slowly building on the previous one until they reach their destination with a comfortable safety factor.

Navigating under walk back constraints could also be an interesting research area for the MDRS. Planning travel routes that satisfy such mission rules is difficult and time consuming. So much so that a full day of planning might be required for each long distance EVA attempted on a real Mars mission.

In addition, it is difficult to know when on the EVA whether you really are within the range of the Hab that you need to be with the amount of suit consumables remaining. Indeed, although I have not yet had time to check the details of today's GPS tracks, I believe the team may have been violating the walk back constraint for as much as a half an hour. This did not occur in reaching Factory Butte but later when visiting one of the interesting sites on the return trip. Unless you are constantly doing calculations regarding your life support and your location relative to the Habitat, you have to rely on approximations and rule of thumb to gauge your compliance. MDRS would be a great location for developing the software and hardware to assist teams in planning and executing EVA's that follow the required safety factor.

Ups and downs are part of life at MDRS. It is nice when the ups outnumber the downs but the problems are truly the best learning opportunities. By continuing work such as this, we hope that first Mars crew will only have to contend with challenges that have already been solved many times over. That is as our goal at MDRS. And the more thought we put into these simulations the more benefits future Martians will reap.