Pow, right to the Moon
by Eric R. Hedman
|If we wait for NASA, Congress, the current and next couple of Presidents to agree on a new course, I think it will delay the return to the Moon until the mid-2030s at the earliest.|
Many people complain about SLS and Orion not being the ideal choice for returning to the Moon. I agree with them it’s not. Many people complain that the proposed Gateway station isn’t in an ideal orbit for the quickest and lowest energy Moon landings. They’re right: it isn’t. Some people complain that it would make more sense to bypass the Gateway and land directly. They’re right that it would be possible to do this. Some people say that we should just wait for SpaceX and their Starship and use it to go back to the Moon. It’s possible that this could work and save us billions of dollars.
Are all these people right that we should change course again and build a more perfect architecture for returning to the Moon? Absolutely not. The better is always the enemy of the good enough. If we wait for NASA, Congress, the current and next couple of Presidents to agree on a new course, I think it will delay the return to the Moon until the mid-2030s at the earliest.
Let’s start with SpaceX and their Starship. If it works as advertised, it has the potential to reduce the cost of returning to the Moon by potentially an order of magnitude and increase the size of the payload and crew delivered by several times. That is, if it works correctly. SpaceX is working on the idea of using transpirational cooling for entry back into Earth’s atmosphere and into Mars’ atmosphere. The problem is that no one has done this on any vessel much less a massive spacecraft. Theoretically it could work. But lots of things that theoretically can work don’t in the real world practically. If NASA were to put the plans under development on hold and bet on SpaceX, what happens if they can’t get transpirational cooling to work or it takes longer to develop than predicted? NASA will have lost several more years and wasted billions of dollars.
If the SpaceX Starship isn’t an option, what else could NASA do? There is currently no other crewed spacecraft capable of travel to the Moon that is ready, or nearly ready, than the Orion capsule. It’s possible that the SpaceX Crew Dragon could be launched on a Falcon Heavy, but it would need some time-consuming modifications. It doesn’t have a service module that can place it into lunar orbit or return it to Earth. It may need upgrades to life support and the addition of features to increase its radiation shielding capability. Both of these would require several years of work. The same issues would apply to Boeing’s CST-100 capsule. That leaves us with only Orion capable of getting people to lunar orbit in the first half of the next decade.
The lunar Gateway station is gaining features that will make it much harder to cancel going forward: international partners. The service module for Orion is being built by Europe along with the ESPRIT module of the Gateway Station. The international habitation module will be provided by ESA and/or JAXA. Canada has agreed to develop the robot arm for the Gateway. Roscosmos may potentially build a multi-purpose module. The US is going to develop the bulk of the components needed, including SLS, Orion, the Power and Propulsion Element, the utilization module, a habitation module, and logistics supply missions. Other smaller partners may commit to developing and building components needed within the station and on the Moon. NASA is also advancing programs for landing robotic craft on the Moon soon and ramping up to landers capable of carrying a crew before the next decade is done.
|But, at some point, people who want us to advance into the solar system have to say, this isn’t ideally what I want; but it will work, and we should move forward.|
What we are getting in my opinion is less than ideal because of decisions made over the years that derailed Craig Steidle’s spiral architecture for the Vision for Space Exploration into Constellation and then into SLS/Orion. What’s done is done. So far, we haven’t figured out how to alter the past. We have to go forward basing our decision upon where we are now. SLS is expensive and won’t fly very frequently. It was supposed to carry an uncrewed Orion capsule and service module to the Moon in 2020 on a mission called EM-1. SLS continues to fall behind schedule and may not be available until 2021.
This past week NASA Administrator Jim Bridenstine said NASA is studying launching EM-1 in 2020 on two commercial rockets launches. In this scenario the capsule and service module would launch into Earth orbit on a commercial rocket, possibly a United Launch Alliance Delta IV Heavy. A second rocket, possibly another Delta IV Heavy or a SpaceX Falcon Heavy, would launch a second stage with a docking adapter on top of it. The Orion capsule and service module would dock with the upper stage, which may be a custom stretched version to carry enough propellant to put Orion on a trajectory to the Moon. Last month Elon Musk CEO of SpaceX said on Twitter, “We’ve already stretched the upper stage once. Easiest part of the rocket to change. Fairing 2, flying soon, also has a slightly larger diameter. Could make fairing much longer if need be & will if BFR takes longer than expected.” NASA is supposed to have the results of the study this coming week.
Whether or not NASA is serious about moving Orion to commercial launchers, the EM-2 mission with a crew is still in the plans to launch on SLS to lunar orbit. Even if this study is just to light a fire under the SLS development team to move faster, it could show that there are viable alternatives to using the horrendously expensive SLS. If, over the next few years, Blue Origin, SpaceX, ULA, or anyone else develops capabilities that make SLS obsolete, the first advantage is that there are options if SLS keeps being delayed or has problems when it is operational. Hopefully, more than one option is developed and SLS can be retired without a gap in our capabilities like we’ve had since the shuttle was retired. It would probably significantly reduce future costs allowing for more frequent missions to the Moon and other destinations.
A Gateway in lunar orbit does give us a foundation and capabilities that can be built upon with spiral development strategies similar to what was proposed in the VSE. We can at a later time move the station to a better orbit if we develop capabilities to reach it doing thing such as building a bigger service module for Orion, or getting Starship to work, or things we haven’t imagined yet. The Gateway may one day be a place to assemble large telescopes or have a fuel depot in place. Extracting propellants from the Moon may turn out to be practical. What the Gateway gives us is a starting point to experiment with options.
|Despite the fact that I think there are better was this could be done, I’m now 100 percent for the current plan.|
I’ve had my misgivings about what we are doing. There have been long stretches with no coherent strategy for NASA’s human spaceflight future. Many decisions are political in nature, overriding engineering and economic common sense. But, at some point, people who want us to advance into the solar system have to say, this isn’t ideally what I want; but it will work, and we should move forward. If we wait for everyone to be satisfied, we’ll go nowhere.
For those who won’t like what NASA’s doing because they think that what they like would make more sense, do you really think that with all the buy in from key partners and money coming into NASA’s budget for this that any other alternative has a chance of being funded in the coming years? I don’t. That is why despite the fact that I think there are better was this could be done, I’m now 100 percent for the current plan. When I think this plan can be improved upon, I’ll say so. When commercial launchers are ready to take over for SLS, I’ll say it’s time it should be done.
We all knew that Ralph Kramden wasn’t ever going to launch his wife Alice to the Moon. He was just expressing his frustration over his issues. Usually, by the end of every episode he said to Alice, “Baby, you’re the greatest.” The space enthusiasts have often been frustrated with the pace of advancement with human spaceflight. That probably will never completely go away. But if NASA and the international partners pull off this return to the Moon, many of us frustrated enthusiasts will say, NASA you’re the greatest.
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