Jim Baen's Universe 1 Vol 1 Num 1: June 2006



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Back to the Moon


Written by Travis Taylor
Illustrated by Laura Givens


 

 

History Repeats Itself?


"As I take these last steps from the surface for some time in the future to come, I'd just like to record that America's challenge of today has forged man's destiny of tomorrow. And as we leave the moon and Taurus-Littrow, we leave as we came, and, God willing, we shall return, with peace and hope for mankind." These are the words said by astronaut Gene Cernan, the commander of Apollo 17, as he stepped from the moon in preparation to return to Earth.

On December 14, 1972, astronauts Harrison Schmitt and Eugene Cernan climbed aboard their Lunar Excursion Module (LEM) and humanity left the moon not to return for at least forty years. Due to the Cold War, lingering aspects of the Viet Nam era, political, socioeconomical and public opinion issues, the general public in America seemed to lose interest in any return to our closest celestial neighbor, the moon. The three decades that followed the Apollo program saw a floundering and almost dying American space program. The days of "Better, Faster, Cheaper" removed the hope of mankind ever returning to altitudes much higher than Low Earth Orbit (LEO).

Atop the failing space program, initiatives were also the failing NASA budget and the failure of its leadership. Poor leadership led to the horrible tragedies of both the Challenger and Columbia accidents. These tragedies all but devastated the already lackluster American space efforts.

But as Apollo 17 astronaut Harrison Schmitt is wont to say, "We do things in fits and starts." And that is exactly where humanity is today—at the beginning of an all new fit . . . an all new start.

On January 14, 2004 President George W. Bush made the following statement:

"Our . . . goal is to develop and test a new spacecraft, the Crew Exploration Vehicle, by 2008, and to conduct the first manned mission no later than 2014. The Crew Exploration Vehicle will be capable of ferrying astronauts and scientists to the Space Station after the shuttle is retired. But the main purpose of this spacecraft will be to carry astronauts beyond our orbit to other worlds. This will be the first spacecraft of its kind since the Apollo Command Module."

The following is a statement made by the newly appointed NASA Administrator Michael Griffin on the second anniversary of President Bush's announcement of the plan to return to the moon, travel to Mars and destinations beyond—a Vision for Space Exploration:

"Two years ago this week, President Bush committed our nation to the Vision for Space Exploration. This Vision commits America to a journey of discovery and exploration with new and exciting plans to return astronauts to the moon. From there, to voyage to Mars and beyond, while continuing to engage in groundbreaking space science and pioneering advances in innovation, creativity and technology. Together with the partnerships we have in the International Space Station program, our nation has the tremendous opportunity and solemn responsibility to lead the way toward the dawn of a new space age."

There is a whole lot more history that took place over the next couple of years between contractors, internal NASA issues, and contractor selection. The project originally started under NASA Administrator O'Keefe. He had his way of doing things—a way that was most apparently the status quo.

Issues began to arise with the contractors and the teams. One of which is that Burt Rutan's team was basically "run off" from the competition due to the "high paperwork burden" required. Burt Rutan and his Scaled Composites team had built the first commercial manned and reusable space vehicle, but NASA's approach somehow led to Rutan's team leaving the competition.

The final competition came down to the usual suspects, Lockheed Martin on one side and Northrop Grumman and Boeing on the other. Lockheed Martin's team basically tried to resell the dead penguin lifting body design that killed the X-33 program and Boeing's design was more like the old Apollo approach with some modifications.

These programs were to go through a spiral development approach following then NASA Administrator Sean O'Keefe's direction. O'Keefe put Rear Admiral (retired) Craig Steidle in charge of the development program. Steidle had used the spiral development effort—quite successfully—for the F-35 Joint Strike Fighter development program. However, that program was a Department of Defense large acquisition program that operates quite differently than the spacecraft development community is accustomed to. The spiral approach was beginning to bog down when the new NASA Administrator Griffin took over.

On June 28, 2005, Griffin made his distaste for the previous management approach quite clear to Congress:

"You asked, what will we be doing different? First of all, I hope never again to let the words spiral development cross my lips. That is an approach for large systems very relevant to DoD acquisition requirements, but I have not seen the relevance to NASA and I have preferred a much more direct approach, and that is what we will be recommending and implementing.

. . . I hope that you will see . . . a straightforward plan to replace the shuttle and a very straightforward architecture for a lunar return that, on the face of it, will seem to you that if we are to do these things, that the approach being recommended is a logical, clean, simple, straightforward approach."

So, we now have a new Presidential initiative to return to deeper space as we did for the Apollo era. And we have a new NASA administrator who is fired up to make some changes to the old ways and to move forward—and back—to the moon. Do we have a plan? How will we do it?

 

How We Will Make it Back to the Moon


The new approach at NASA has been a complete change from the previous development approach. In the summer of 2004 Griffin, while at John's Hopkins Applied Physics Laboratory before he was named O'Keefe's successor, participated in a study for NASA called Extending Human Presence into the Solar System. The study suggested three stages.

Stage 1 – develop the crew exploration vehicle (CEV), finish the International Space Station (ISS), retire the Shuttle Orbiter as soon as possible.

Stage 2 – develop an updated CEV capable of multiple month long manned missions, with components required to enable human flight to the moon and Mars, Lagrange points, and various near-Earth asteroids.

Stage 3 – develop human-rated planetary landers such as the LEMs of the Apollo era.

The new program is called Project Constellation and President Bush's budget request in 2005 was for $428 million and $6.6 billion over the next five years. The budget request was for the development of the CEV and, in fact, was confirmed by Congress with the full amount of funding requested by the President.

So, what to do now? Well, NASA, under the new Administrator Griffin, set up a study to determine what would be the best way to really get started back into space. The Exploration Systems Architecture Study, affectionately referred to as ESAS in NASA-speak, was initiated. In large, the ESAS study derived similar conclusions as the study effort previously done by the Extending Human Presence into the Solar System effort.

The ESAS study has led to the development of some new space vehicles. These vehicles are known now as the Exploration Launch Vehicles. The Exploration Launch Vehicles Office has developed the scope of the development effort as such:

Crew Launch Vehicle (CEV) – a single five segment reuseable solid rocket booster that is human-rated (RSRB/M) and has an upper stage that is powered by a single engine derived from the old Saturn V J-2 rocket engine

Cargo Launch Vehicle (CLV) – a system that has a core stage derived from the Space Shuttle External Tank with five Space Shuttle Main Engines (SSMEs) powering it. Atop the core stage is a large cargo container. Also attached to the core are two of the five segment RSRB/Ms.

Earth Departure Stage – this component of the Exploration Vehicles scope is the upper stage that is attached to the CLV and will be the all important system for getting out of Earth's orbit and to the moon. The upper stage component uses tankage derived from the Space Shuttle's External Tank and is powered by a single J-2 engine.

The concept is actually brilliant from a paperwork and reinventing the wheel perspective. In order to put a human being on top of any spacecraft, a literal mountain of paperwork must be completed. Most of the paperwork involves proving that each individual component of the spacecraft down to the screws, nuts, and bolts have flown before and are of a quality that they have an extremely low risk of failure. A spacecraft of the CEV or CLV stature will have as many as two million separate parts. If each of those parts have a handful of forms to be filled out, checked off, and so on, the paperwork nightmare becomes apparent.

But what if there were a whole bunch of parts that have already had the paper work completed on them? In that case there would be no need to reinvent the wheel and fill out all that paperwork again. So, the ESAS group developed the brilliant Exploration Launch Vehicles plan.

The CEV is based on the SRBs flown with the shuttle and an upper stage engine flown in the Apollo program. The CLV and Earth Departure Stage follow the same approach. But were there not problems with the shuttles that caused the Challenger and Columbia incidents?

Of course there were, but again this is really clever, those components are left out. The problems that caused the Challenger incident were due to the SRBs having thrust exhaust leaks around the segments of them. This hot exhaust heated up the External Tank and caused it to explode. That problem was due to the old SRB design and the operation protocols being violated. That problem was fixed long ago.

The Columbia accident was due to foam falling off the External Tank and damaging the Orbiter's heat shield tiles. That problem was solved by there no longer being an Orbiter and all of the crew and payload components are above the tankage. Therefore, nothing can fall off the tankage and damage the crew components. Oh, and by the way, the crew will be returned in a capsule and re-enter just like the Apollo astronauts did except that they will land on land the way the Russians do it, instead of water.

Brilliant!

Sounds a lot like the old Apollo, doesn't it? Well, Apollo worked well and the SRBs in the shuttle program have worked well. So, the new plan is to take the best of both worlds and marry them together with modern computers, modern design and fabrication techniques, and new flight systems and avionics.

 

The Mission Profile


So here is how a mission might go. The crew of three to six astronauts will climb aboard the CEV. They will launch about the same time the unmanned CLV is launched. Atop the CLV in the cargo compartment is the Lunar Surface Access Module, or LSAM, which is an updated version of the Apollo LEM.

The RSRB/Ms will fall back to Earth to be refurbished for future launches just as the SRBs do with the shuttle. The CEV upper stage will meet and dock with the CLV upper stage, which contains the Earth Departure Stage and the LSAM. The docking will be much like the Agena module and the Gemini spacecraft docked, or the same as the Apollo Command Service Module (CSM) and the LEM docked in LEO.

Now all mated together, the Earth Departure Stage fires its modernized J-2 engine. The thrust from the engine places the CEV and the LSAM into a translunar insertion trajectory and the Earth Departure Stage is then jettisoned.

As the CEV/LSAM approaches the moon, a burn of the LSAM engine is made to put the spacecraft into a lunar orbit. This is called a lunar orbit insertion maneuver. Then the CEV and the LSAM separate just as the CEV and the LEM of the Apollo program did. The CEV will continue to orbit the moon while the LSAM descends to a lunar landing.

At this point the LSAM is on the moon. Whatever the lunar mission of the day is will be undertaken. Once the mission is completed, the crew will climb back into the LSAM and fire the Ascent Stage. The Ascent Stage portion of the LSAM lifts the crew back up to meet with the CEV. Once the CEV and the Ascent Stage dock the crew will leave the Ascent Stage. The CEV is then sealed up and the Ascent Stage is jettisoned.

The CEV then fires its engine in a transEarth injection maneuver. Once the CEV engine is used up it is jettisoned, leaving just the Crew capsule. The Crew capsule then re-enters Earth's atmosphere directly and will land with parachutes at a predesignated land-based landing zone.

Mission completed and everything is A-OK!

How Does the New Spacecraft Compare to the Apollo?


 

 

The CEV is the smallest of the two new spacecraft systems. It will be about three hundred nine feet tall with a total lift-off mass of two million pounds. It will be able to lift about fifty-five thousand pounds to LEO. Recall that this spacecraft will implement one five segment RSRB/M with an upper stage that uses the modified J-2 engine. The J-2 engine uses liquid oxygen and liquid hydrogen for oxidizer and fuel.



The CLV will stand three hundred fifty-eight feet tall and will have a total lift-off mass of about six million four hundred thousand pounds. It can lift one hundred and twenty-one thousand pounds to a trans-lunar injection. This spacecraft uses two of the RSRB/Ms and five SSMEs for the core stage and a single J-2 engine for the upper stage.

The original Apollo spacecraft was the Saturn V. It stood three hundred sixty-four feet high and had a total lift-off mass of about six million five hundred thousand pounds. It consisted of three stages. The first stage consisted of five F-1 engines that ran off of liquid oxygen and rocket propellant. The second stage was five J-2 engines. The third stage was one J-2 engine.

When we consider the combination of the CEV and the CLV spacecraft designs and compare them to the Apollo spacecraft we can realize that the new system is indeed an upgrade and not simply a copy of the old ideas. The CEV/CLV combination will enable a larger payload to be delivered to the moon. This means more crew and more science will be enabled.

There is another need for the two different spacecraft—the CEV and the CLV. The CEV will be needed immediately to carry crew and small amounts of supplies to the International Space Station. The CEV will most likely be the first system developed to flight readiness.

The CLV has a complete other use that most people have yet to realize. We no longer have any Titan rockets and if the Space Shuttle is decommissioned the U.S. will have lost its capability to place heavy payloads into Earth orbit. An example of these payloads might be the Hubble Space Telescope. Only the Space Shuttle or a Titan could lift such a payload to the proper orbit. If the shuttle is gone before the James Webb Space Telescope is completed, how do we expect to get the thing into orbit?

What about other national assets that are needed for defense purposes and intelligence gathering purposes? It is likely that those payloads are large as well. What about commercial very large relay systems like the Tracking and Data Relay Satellite System or TDRSS? How will we get next generation systems up without the shuttles or Titans?

The CLV can do it! We will not need the upper Earth Departure Stage. Instead of that part of the vehicle, we can place the heavy payloads there. The CLV might even offer us the capability to launch systems with payloads larger than Delta IVs and Atlas Vs can handle to higher orbits such as geosynchronous ones.

So, in the near term, as the shuttles are decommissioned we might have to take these new NASA spacecraft and implement them with a dual use. That is a good idea. That is one of the smarter things NASA could do or could have done in the last few decades. At this point, it is unclear if NASA has thought of this potential dual use of the Exploration Launch Vehicles. On the other hand, it is likely that the air force has. And with Griffin's previous ties to DoD and the intelligence community it is most likely that he has considered this as well.

 

So What Are the Long Poles? Why Should We Go Back?


An overview of the program does not really reveal any hard technology problems. Most all of the technologies being considered for the Exploration Launch Vehicles are flight tested from heritage spacecraft such as the shuttles and the Apollo programs. The biggest hurdle appears to be maintaining enthusiasm for the mission. What do we do once we get to the moon?

We are no longer in a Cold War era space race with the Soviets—although many would argue that we are in a Cold War-like space race with the Chinese—so getting there first cannot be our goal. NASA Administrator Griffin has created a team of high ranking NASA officials to investigate our long term moon goals. Why are we going back?

Well, to start with, the moon is a lot closer to Mars and is a good place to practice leaving Earth and going to another space body with manned systems. If we can't go back and forth between the earth and the moon, how do we expect to go to Mars? It will be good practice and an excellent method of flight testing our concepts and technologies.

We have no idea what the moon is all about. We have studied the moon with probes and a few manned missions and from telescopes, but there is a lot about the moon that we simply do not know. There are deep craters near the poles that have perpetual shadows over the floor and some of these have given confusing readings to various probes. Some of the probes have detected high levels of hydrogen and other substances that seem out of place. We simply do not fully understand what the moon is, how it got there, and what we can do with it. We never knew there was gold in California until we got there and started digging around in the dirt. Perhaps the moon will hold similar riches. Keep in mind that the riches will have to be large, to overcome the cost of the expedition through space to the moon.

What about for other scientific purposes? The far side of the moon is an ideal place for radio astronomy as there is no "noise" from terrestrial radio communications there. It would also offer a platform for other astronomical observation posts as the moon has no atmosphere to interfere with the electromagnetic signals coming from outer space.

Finally, there should be a military outpost there. What!? A military base on the moon!? Why not? Think of it this way. What if global diplomacy collapsed and China or Russia or any other country decided to destroy the United States of America's defense capabilities. If somehow all of our bases and military resources were wiped out then we would be defenseless. But, if there was a contingent of forces on a base on the moon they would offer us a last resort. As with Heinlein's The Moon is a Harsh Mistress, we could implement a railgun on the moon that could hurl projectiles to Earth which would cause destruction of enemy targets far better than nuclear devices without the undesirable radiation fallout. Of course, there are some major technical hurdles for such a system, but it is feasible.

Also consider that same railgun system as a possible defense for asteroids, meteors, and comets that might be on an impact trajectory with Earth in the future. This could be a major reason for having a military base on the moon. As it stands currently, we have no line of defense for such impacts.

And then there is the other big science fiction possibility—mathematically it is a finite probability—that the Earth is invaded by aliens. Having our military in multiple locations might be useful in that situation. Having humanity spread out in multiple places wouldn't be a bad idea, either.

Well, one thing for certain though, militarization of the moon is a long way off. So, if you are one of those types that is opposed to such an idea, then don't panic. There is plenty of civilian exploration to be had on the moon. There is plenty of science to discover and uncover on the moon. Perhaps some smart entrepreneur will develop an economically viable business model for moon missions. Maybe there will be a Club Med Tranquility Base in the not so distant future.

Whatever the outcome is, the thing to remember is that there is a big bright future for space exploration that starts on the moon. And, if there are ideas that you have for reasons for going and staying on the moon, by all means don't keep them to yourself. NASA is looking for great ideas and applications for space travel. What to do once we get to the moon is such a question that Administrator Griffin had these words to pass along in an E-mail to his upper echelon advisors:



The next step out is the moon. We're going to get, and probably already are getting, the same criticisms as for ISS. This is the "why go to the moon?" theme.

We've got the architecture in place and generally accepted. That's the "interstate highway" analogy I've made. So now, we need to start talking about those exit ramps I've referred to. What ARE we going to do on the moon? To what end? And with whom? I have ideas, of course. (I ALWAYS have ideas; it's a given.) But my ideas don't matter. Now is the time to start working with our own science community and with the Internationals to define the program of lunar activity that makes the most sense to the most people. I keep saying—because it's true—that it's not the trip that matters, it's the destination, and what we do there. We've got to get started on this.

. . . and the International Partners to get started down the track on pulling together an international coalition. They are annoyed and impatient with our delays since the Vision speech. We need to be, and be seen to be, proactive in seeking their involvement. We need to work with them, not prescribe to them, regarding what we can do together on the moon.

Beyond the moon is Mars, robots first. Most of the Internationals are at present more interested in Mars, as I hear the gossip. Fine, we can't tell them what to be interested in. But our road to Mars goes through the moon, and we should be able to enlist them to join on that path.

Everyone . . . wants to be part of making exploration what NASA does. It won't survive if all we worry about is getting there. That was the essential first step. But it has to sell itself on what it is that we DO there.

 

So When are We Going?


As the program currently stands, NASA plans to be testing the systems for the CEV as early as this year. Design studies and reviews are to begin no later than 2008. Suborbital flight testing of the spacecraft is to begin sometime around 2009 to 2010. There are at least three so-called "risk reduction flights" scheduled between 2010 and 2012. The hopes are to have the CEV flights proven and ready for operation by 2012. This will allow decommissioning of the shuttles as the CEV will be able to transport crewmembers to the ISS.

 

The heavy launch vehicle, CLV, will be developed parallel to the CEV. However, the flight readiness of the CEV seems to have priority status. The current NASA plan is to implement what Griffin refers to as the "Lunar Sooner" plan that will see flight testing of the CLV sometime between 2013 to 2016 with flight readiness soon after. The "Lunar Sooner" plan optimistically has the CEV and CLV ready for the first manned Moon mission by March of 2017! That is only eleven years away and is three years ahead of the original schedule suggested by President Bush. So just be patient, we are liable to make it back to the moon within the lifetimes of the majority of people that are reading this article!



ADD NOTE:

"Since this article was written NASA has solidified the CEV program more and has chosen new descriptions for the launch vehicle systems. The small capsule that carries the crew will be the Crew Exploration Vehicle or CEV. The modified solid rocket booster and the liquid fuel upperstage that lifts the CEV into orbit is the Crew Exploration Vehicle Launch Vehicle or CLV. The larger system that lifts the LSAM and other cargo into orbit will be known as the Cargo Launch Vehicle or the CaLV."



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Travis Taylor is the author of several novels.
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