Diary of an astronaut

 Space Shuttle Atlantis

Space Shuttle Atlantis after it arrived at the launch pad Aug. 2

Steve MacLeanLater this month, York alumnus Steve MacLean (right) (BSc ’77, PhD ’83, D.Sc ’93) is scheduled to fly to the International Space Station on board the Space Shuttle Atlantis. MacLean, a member of the board of the York University Alumni Association, has written a diary recounting his activities as he prepares for the launch, expected to take place on or after Aug. 27. Earlier this summer, MacLean was also featured in a YorkU magazine cover story about his career as a Canadian Space Agency astronaut working with NASA on the shuttle program. This will be 51-year-old MacLean’s second flight into space – his first was in 1992 – and his first space walk. Watch the Alumni Web site for possible updates.

Aug. 5, 2006 – 22 days to launch

On Aug. 27 NASA will launch our 12-day mission to the International Space Station. We are the first assembly mission since the Columbia accident on Feb. 1, 2003. In our cargo bay, we will carry a station truss (left) identified as P3/P4, which just means the third and fourth truss on the port side. Integrated into this truss is the second of four sets of solar panels. The first one was installed by Marc Garneau on his mission in 1999. I will install this second truss on Flight Day 5 using the Station Arm or Canadarm 2 and the Canadian Space Vision System. On the following day, my crewmate Dan Burbank and I will perform our first space walk…definitely a personal highlight.

At NASA, space walks are called EVA, for Extravehicular Activity. During this seven-hour EVA, we will be out at the end of the truss preparing the solar panels for deployment. In particular, we will unlock a 10-foot-diameter rotary joint so that the panels can track the sun throughout each orbit. On Flight Day 7, after we have deployed the solar panels, we will have effectively doubled the power available to the International Space Station. I am pleased that this redundant power path will make the station inherently safer for the long-term increment crews.

We are in the last steps of our training and the weeks have been intensive, busy and quite exciting. When I explain to my children what I am doing each day, they are jealous. But only because they think my job sounds like I am at summer camp…permanently!

Last Friday, July 28, I had my certification for my Safer run; the Safer is our “Buck Rogers” backpack that is an integral part of our spacesuit. In the computer world of virtual reality, the instructors artificially cut your tether and force you to tumble off and away from the space station. Thirty seconds later, they allow you to turn on your thruster backpack. With your hand controller you stabilize your tumble, find the station and fly yourself back to the point on the station where you fell off. If you make it back safely, you pass and you are certified to fly!

Right: Artist’s drawing of completed International Space Station. The P3/P4 truss is located on the far right

It is interesting to note that flying in space while orbiting Earth is not intuitive. Johannes Kepler figured this out hundreds of years ago: if you speed up, you will raise your orbit; if you raise your orbit, orbital mechanic effects will cause you to go slower and you will not be able to catch up to the station. If you slow down, you will lower your orbit; when you lower your orbit, orbital mechanics will speed you up and only then can you catch up to the station. So to speed up, you must slow down and vice versa. However, once you get closer to the station, the orbital effects are minimal and flying is intuitive again. As I hope you imagine, this is contingency training. In theory we should always remained tethered to the station.

July 31: Dan and I had our second-last EVA training run at the Neutral Buoyancy Laboratory (NBL). The NBL is a pool 200 feet long by 100 feet wide and 40 feet deep. Full-scale mockups of the station are distributed in a modular fashion in the pool. The external fidelity of the mockups is exact and the training is essential to mission success. On Tuesday, Joe Tanner and Heide Piper, the other EVA team, had their second-last NBL training run. Dan and I shared the communication duties, just like we will on orbit, acting as cockpit choreographers for their run. Wednesday of this week we had our last integrated Entry Simulation. Here we practised the last eight hours of space flight finishing with the landing at Kennedy Space Center. We wore the full launch and entry astronaut suits, the instructors threw a series of landing malfunctions at us and we interacted with Mission Control just like we would on the real day. On Thursday, we had our “last” NBL training run. We opened the hatch at exactly the same time as the EVA that was taking place on orbit that day. Dan and I were the contingency “go-to” team in case the on-orbit team ran into difficulty. Upon finishing our last run Thursday afternoon, I really felt the excitement generated by all the support personnel. Atlantis was at the pad, our payload was installed and we all had that tremendous feeling of “the next time we put this EVA suit on, it’s for real.”

Aug. 2, 1:07am: Space Shuttle Atlantis left the Vehicle Assembly Building for the launch pad 3.5 miles away. Moving and creaking at approximately 0.5 miles an hour she arrived at the pad at 7am.

One day later, on Aug. 3, our payload, the P3/P4 truss, was installed in the Shuttle while in its vertical position out at the pad. The truss pictures give you an idea of the size of payload. They show the payload leaving the Space Station Processing Facility on July 21.

Aug. 7:  We fly via T-38 to the Kennedy Space Center for the Terminal Countdown Demonstration Test. This is a full dress rehearsal of the launch. Over the following three days we will execute all the steps of the countdown except for the actual ignition sequence for the rocket engines.