This morning we woke up early to start our dive on the reef before the sun came up. Mike G. and Mike L.A. were up at 5:30 to have breakfast and get ready to enter the water by 6:30. Bill and I were up at 5:45 for a quick breakfast before getting suited at 6:30 to be in the water by 7:00. I had oatmeal, some Gatorade and an apple and headed out to the wet porch still only really half awake. However, climbing into a cold wet dive skin and then a wet suit is a great way to wake-up first thing in the morning! The water was still dark black, like on our previous night dive, as we descended into the moon pool to put our tanks on. Once again we attached a luminescent marker to our tanks so that we could easily see each other underwater. We double checked all of our equipment, primary and back-up flashlights and headed out to rendezvous with Mike and Mike.

The goal of the dive was to head out SE excursion line to an area close by the Pinnacle way station to continue the reef science that we had been doing in the area yesterday. As we swam along the water started to lighten toward the east and we could look up to see the sun beginning to penetrate down towards us at 50 feet. There didn't seem to be much activity on the reef - almost as though the fish were waking up to start their day as well. A group of barracuda swam in formation 15 feet to our left and slightly behind us, insolently ignoring the fact that we were much larger than they were. The bioluminescence was not as marked as it had been on our night dive. Perhaps due to the fact that the sun was now above the horizon and the night was quickly giving way to light.

We arrived at the Pinnacle way station and checked in with Aquarius before starting to photograph and document the condition of corals in the vicinity of the transect lines we put down yesterday. Having four aquanauts made the data collection much faster and we were able to finish two transects and a swath before we had to head back to the habitat. As we swam back I could not help but reflect on the fact that this would be our last dive together on the mission. After a week underwater our motions were much more fluid and there seemed to be an almost intuitive understanding of the tasks for each diver as we worked together. I will truly miss working with this team, it has been a great experience. We stopped to take photographs of each other on the way back and stopped to have a look at the lobsters and eels that we knew lived under the coral heads. As we surfaced in the wet porch it seemed to me that this had been one of the best dives of the mission, one that I will remember for a long time.

After cleaning our equipment and changing we quickly got ready for an educational event with the Webster Intermediate school in Houston. By now we were pretty adept at getting things set-up for the event so we had no problem having a quick snack and getting ready to go in 15 minutes. This time we did the event with all 4 aquanauts in the habitat and it worked very well as we each had a chance to answer the myriad of questions from the students. After we signed off it was time for lunch and the start of a fairly lengthy process of cleaning the habitat and getting ready for the 17-hour decompression back to sea level pressure. This is a fairly complex procedure in which we closed the water-tight doors between the entry lock and the wet porch. This isolated the entry lock, main lock, and crew quarters from the wet porch. Pressure in the wet porch remains equal to that of approximately 48 feet (ambient) at all times. Thus, the wet porch does not flood while we the remainder of the isolated habitat is brought up to the equivalent of sea level pressure. This process is done gradually to prevent the aquanauts from getting decompression sickness, a medical problem associated with the dissolved nitrogen in our body coming out of solution as gas bubbles if we proceeded too rapidly. We started the process at 4:00 pm with a series of 20-minute sessions breathing oxygen to help remove the nitrogen from our bodies. Each session was separated by an air-breathing interval to prevent problems with oxygen toxicity and the protocol called for two 20-minute sessions with the final session lasting 30 minutes. All of us were happy when we finished that segment of the protocol as the masks had to have a tight seal and the oxygen had a drying effect in our nose and mouth as we breathed it. We settled in our bunks to watch movies until it was time for bed as we wanted to keep the circulation to our arms and legs as efficient as possible to help remove the nitrogen.

I fell asleep at around 10:00 pm since we were scheduled with an early wake-up at 4:30 am to finish the remainder of the protocol and get the habitat ready to be shut down and repressurized back to a depth of 48 feet. Lying in bed, I had a feeling similar to that the night before returning from space to land at Kennedy Space Center at the end of 16 days in space. I was not really ready to leave, the desire to remain in the habitat was strong. So too was the desire to get back to the surface world and see our friends and family and reminisce on what it was like to become a reef inhabitant for a short period of time. It has indeed been an amazing experience.