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Building an outpost in space
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: August 25, 2006

The international space station was born in President Ronald Reagan's 1984 State of the Union address. Reagan told the American public the station would cost $8 billion and be ready for operation by 1992, the 500th anniversary of Columbus's discovery of the new world.

It didn't quite work out that way. The $8 billion was misleading at best because it did not include shuttle transportation costs. Shifting requirements and concern in Congress led to numerous redesigns, culminating in the early 1990s with a Clinton administration decision to invite the Russians to participate in the program.

The Russians were building their own space station, Mir, but in the wake of the Soviet Union's collapse, the writing was on the wall: neither nation could afford to go it alone. The Clinton administration also saw a joint space station as a peaceful project for Russian space scientists. And so, after using Mir to work out flight control procedures, Russia launched the first international space station module in 1998. The first U.S. module followed suit three weeks later and construction began in earnest.

Then came the Columbia disaster, stopping assembly in its tracks and forcing NASA and the Russians to drastically scale back station operations. Crew size dropped from three to two because without the shuttle, there was no way to launch enough water and other supplies to support a three-person crew.

While NASA was struggling to recover from the Columbia accident, the Bush administration was rethinking the nation's space policy. Based in part on recommendations from the Columbia Accident Investigation Board, Bush unveiled a new space initiative in January, 2004, ordering NASA to complete the station and retire the shuttle by 2010 and to develop a new manned spacecraft to service the station and eventually to carry astronauts back to the moon.

When Columbia broke apart on the way back to Earth, Jett and his crewmates already were training for their mission. NASA envisioned nearly 30 space shuttle flights to build, outfit and supply the international space station before assembly would be declared complete.

Suddenly faced with the Bush administration's 2010 deadline, NASA pared the assembly sequence to the bone, chopping about 10 missions and leaving a manifest with just 17 flights - 18 counting a yet-to-be-approved mission to service the Hubble Space Telescope - and two contingency missions.

Along with downsizing the station, the lab's scientific justification has changed as well. The project originally was sold on the research that would be conducted aboard the outpost, a tough sell given the enormous cost of the project: More than $100 billion through the first 10 years of operation.

The goal now is to finish the station, attach European and Japanese research modules as part of long-standing commitments and use the outpost to test hardware needed for the eventual exploration of the moon and Mars and to learn more about how the space environment affects human physiology.

"From my perspective as an engineer, which I admit is biased, the main purpose of the station is to learn how to live and work in space," Griffin told CBS News in a recent interview. "Whenever humans are ready to go to Mars, we're going to need an amount of hardware in space about the size of the space station when it's done. That's how much we need to go to Mars. And hopefully we will have learned so much from how we've assembled station that we'll do a great job on it. It won't take us 20 years to put together the hardware to go to Mars because we'll have learned."

That's not to say Griffin would have built this particular space station if he'd been involved in the original decisions.

"People should understand, from where we are at this point in time, the right thing to do is to fly out the shuttle to retirement and use it to assemble the station. OK? Because otherwise, we're not taking advantage of the investment we've made," he said. "Now, what is true is that I think we did things in the wrong order. The right approach to running the nation's space program would, in my mind, never have been to abandon going to the moon as we did in the early 70s. I've characterized that over and over again as one of the many unfortunate decisions to come out of the Nixon administration.

"That said, that decision was made and other consequences followed from it, one of which is we built the shuttle and declared the space station to be the major project we would use it for. And we've been working on the station now for 22 years.

"Now if you ask me, when people say I would never do this, they've got it wrong. If you want to go to Mars, the building of a space station is an important step along that way. It's possible to go to Mars without having built a space station, but I think in preparing for a voyage to Mars, a space station is a step along the way and I would have done that. I would not have done it in this way, I would not have done it in 25,000- or 30,000-pound chunks at a time over dozens of shuttle flights. I would have done it more like we did Skylab, where we put up 200,000 pounds at a time.

"As an engineer, the way we went about it, because of the order in which we made our decisions, offends me," Griffin said. "I'm offended as a technical person, because I don't like the way in which we did it. But no one will ever get me to say that a space station is not a valuable step along the road to Mars. If I've not been clear with these comments, ask me again and I'll clarify. Because what Mike thinks is often misreported by those who don't even bother to ask me the question."

The international space station currently consists of six pressurized modules. At the back end of the outpost is the Russian Zvezda command module featuring two solar arrays and an aft docking port that can accommodate Progress supply ships or Soyuz capsules. An airlock module called Pirs is attached to a downward-facing port on Zvezda's front end. The module forward port is attached to the Russian Zarya module, a supply and propulsion module equipped with its own pair of solar arrays.

Zarya's front end is bolted to a pressurized mating adapter that, in turn, is attached to NASA's Unity module, a multi-hatch node with six ports. Its starboard port connects to the U.S. Quest airlock module while its upper zenith port accommodates the Z1 truss and the P6 solar arrays. Unity's downward facing port is used by cargo modules brought up by the shuttle and its port hatch is home to another pressurized mating adapter that will be relocated later in the assembly sequence.

Unity's forward port is attached to the Destiny laboratory module. On the forward end of Destiny is another pressurized mating adapter used as a docking port by visiting space shuttles. On top of the lab module is the station's main solar array truss, which is mounted at right angles to the long axis formed by the pressurized modules.

The S0 truss sits in the middle atop the lab, flanked by the S1 and P1 truss elements. S1, S0 and P1 house a variety of electrical components and the station's main ammonia cooling system, including huge articulating radiator panels.

The lab module also is home to the station's Canadarm 2 robot arm, a marvel of engineering that is capable of moving, end over end like an earthworm, from work site to work site on the solar array truss.

During Atlantis' flight, the P3/P4 truss elements and solar array panels will be attached to the left side of the truss. In December, an even more complicated flight is planned to attach the P5 spacer truss, activate the space station's main ammonia cooling system, retract the port wing of the P6 solar array and tie the new P4 arrays into the lab's electrical system. Hill said STS-116 will be even more challenging than Atlantis' mission.

"Getting P3/P4 installed and activated, both those solar arrays out, getting that SARJ checked out and turning, which is something we've never done in orbit, those are big steps," Hill said. "All this reconfiguration we have to do on 116, those are big steps.

"That flight right there and that choreography is something that when we first came up with this sequence in 1994, we all sat back and said wow, how are we going to figure this one out? Today, the folks who have been leading that effort feel pretty good they've got their arms around it but they're also really worried and keeping their fingers crossed that everything goes well."

With P5 installed and the port wing of P6 retracted, another shuttle crew will visit the station in February to retract the starboard P6 array and to attach the S3/S4 truss and solar array segments on the right side of the station's main truss. The S5 segment will be carried up next June along with a power transfer system that will let space shuttles plug into the station's electrical system to extend their stays at the lab.

Next August, the P6 arrays will be repositioned and extended on the port side of the truss and a new multi-hatch module - Node 2 - will be delivered. Between shuttle flights, the station crew will reposition Node 2, using the Canadarm 2 to move it to the front of the U.S. Destiny laboratory module to provide the docking ports needed by European and Japanese research modules.

"Moving P6, retracting those solar arrays and then unplugging that truss segment and moving it outboard, that right there is the single most complicated and hairiest thing we're doing in building the station," Hill said. "We've known that from the get go.

"You've got to reach out and install it without bonking into either one of the two P4 solar arrays while you're doing it, you've got to get it done on time because that guy's getting cold from the point you turn it off and unplug it. You need to get it attached and reconnected so you can fire up that hardware. If the solar arrays go back in the can, the rest of it ought to go pretty lickety split."

Whether the P6 arrays will, in fact, roll up as required remains to be seen.

"The guys who built it, they designed it to retract and they expect it to retract," Hill said. "But for a solar array that's been hanging out in the breeze, where if we took a (space debris) strike and dinged one of those structural elements, there's a real good chance that we're not going to be able to fully retract those arrays. We'll see what we get."

Next September, the European Space Agency's Columbus research module will go up, followed over the next three flights by components making up Japan's Kibo research modules and external platforms. In June of 2008, the station's fourth and final set of solar arrays will be delivered. The last major module, Node 3, is scheduled for attachment in January 2010.

By the end of assembly, the international space station will weigh nearly 1 million pounds and have the pressurized volume of two 747 jumbo jets. Its finished solar array truss will stretch the length of a football field and its eight huge solar array wings will generate some 75 kilowatts of power, enough to supply 55 average homes. Crew size will be bumped up to six astronauts and cosmonauts by early 2009 with Russian Soyuz spacecraft and NASA's new Orion capsules providing crew ferry and lifeboat capability after the shuttle is retired.

"The international space station originally was conceived as a world class research facility," said Mike Suffredini, space station program manager at the Johnson Space Center. "It will continue to provide that capability for research that you can do in space that can open our eyes to problems on the ground. Today, we have a number of plans to up the research capability, the research suite of hardware, during the assembly process such that we will be able to utilize it.

"However, what we look to ISS for as well is the exploration," he said. "We will use it to test systems that we plan to utilize on the moon and Mars, it's going to be really critical that we build highly reliable systems. The best place to test systems, particularly that have to operate in a zero-gravity environment, would be on the space station.

"In addition to that, we need to learn to operate in the limited logistics fashion. We've learned quite a bit over the last three years. The third, which is critical as well, is studying human physiology and the psychology of long-term stays in space."

Suffredini said the station also would serve as a proving ground for the new Orion crew exploration vehicles that eventually will replace the space shuttle. As it now stands, Orion is not expected to begin carrying astronauts until the 2014 time frame. During the gap between the end of shuttle operations in 2010 and the advent of Orion, NASA will rely on commercial agreements with the Russian space agency to launch U.S. astronauts on Soyuz spacecraft.

While larger and more capable than the venerable Soyuz, the new Orion spacecraft will not be able to match the cargo delivery capabilities of the space shuttle. Some critics have questioned whether NASA can keep the station going without the ability to launch large spares when components break down, but Griffin said that will not be a major problem.

"With the Ares 1 launch vehicle and the (Orion) CEV, we're deliberately building in a substantial amount of flexibility," Griffin told CBS News. "The Ares 1 can be launched in an unmanned mode, it can be launched with the service module and not with the command module and can be used to take up unpressurized cargo in that fashion to the station, including (gyroscopes) and other (large) things.

"So we're designing the system to be modular and adaptable and flexible so it can do much, not all, but much of what the shuttle does today," Griffin said. "The shuttle has enormous capabilities, not all of which we will be able to replicate in the CEV system. But we're going to capture a good deal of it and we can, we absolutely can use the CEV and the Ares 1 launch vehicle to sustain the space station."

PREVIEW REPORT PART 4 --->


STS-115 patch
The official crew patch for the STS-115 mission of space shuttle Atlantis to resume orbital construction of the International Space Station.
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