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It’s been decades since humans set foot on the Moon. Well, it’s time to go back, in theory. Of course, we’ve heard this all before. What are the plans afoot to send humans back to the Moon this time. What hardware will we use, and what other strategies are in the works to make this happen?
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Show Notes
Luna-2 – first mission to successfully reach the moon (Soviet mission)
Ranger-7 – first American mission to successfully reach the moon
Surveyor missions – first soft-landing, and sent data
Lunar Orbiter 2
Human Spaceflight
Apollo Program
Apollo 8 – first manned mission to the moon
List of Moon missions
Space Launch System
SpaceX Falcon Heavy
Deep Space Gateway
Chinese Lunar Exploration program
SpaceX BFR
Transcript
Transcription services provided by: GMR Transcription
Fraser Cain: Astronomy Cast, episode 477, “The State of Exploration: The Return to the Moon.” Welcome to Astronomy Cast, your weekly facts-based journey through the cosmos where we help you understand not only what we know, but how we know what we know. I’m Fraser Cain, publisher of Universe Today. With me, as always, is Dr. Pamela Gay, the director of technology and citizen science at the Astronomical Society of the Pacific, and the director of CosmoQuest. Hey, Pamela. How are you going?
Pamela Gay: I’m doing well. How are you doing, Fraser?
Fraser Cain: Great. This is the last episode before I head off to Iceland with my good buddy, Dr. Paul Sutter. Now, we’re gonna record another episode, I think, tomorrow to try and get another one in the bank. But I think at the time you listen to this, I will be in the air and on my way to go see auroras from Iceland, which is full on bucket list. So, I cannot wait.
Pamela Gay: So, this is super cool. So, what date do you finally return so that we can start hearing your tales.
Fraser Cain: 12th.
Pamela Gay: You will be back on the 12th. Okay. So, you’re only gone one Friday, and we’ll have a story – everything sounds excellent. And the day after our next recording, that we’re together when you get back, that’s February 16th. And on the 17th, I leave to go to the European Testing conference in Amsterdam. And I’m doing a meet up in Amsterdam on the 18th. So, all of you in Europe, check out our website. There is an Eventbrite event in Amsterdam, near the train station. So, if you want to train into the city, it’s super easy. RSVP so I know how much of the little café I found to sequester off. And I will have free things to give anyone who shows up. I just need to know how many of you there will be.
Fraser Cain: And I think I mentioned this last week, but I’m not sure I did. So, the plans are coming together for me to do this other bucket list, which is to go to Australia. So, July 7th and 8th, 2018, I’m going to be at Byron Bay, Australia for an event called Star Stuff 2018. And Amy Shira Teitel’s gonna be there and a bunch of other people who I’m really excited to meet. Geoff Notkin, one of the meteorite guys.
Pamela Gay: Oh, he’s fabulous.
Female Speaker: Yeah. Terry Lovejoy is gonna be there. So, there’s gonna be some amazing astronomers. But we’re gonna go for longer, my wife and I, so I don’t really have any plans yet on what I’m gonna do in Australia. So, I know that when the Australians find out that we’re coming to the Southern Hemisphere, they try to get their claws into us and try to have some fun events. So, if you’re in Australia and you want to organize things while I’m around, let me know. And I’d love to sort of, maybe, think about some other events and stuff that we can do. All right, let’s get on to this week’s show.
It’s been decades since humans set foot on the Moon. Well, it’s time to go back, in theory. Of course, we’ve all heard this before, what are the plans afoot to send humans back to the Moon this time? What hardware will we use? And what other strategies are in the works to make this happen? Okay, Pamela, how long has it been since human beings set foot on the Moon?
Pamela Gay: It was before either of us were alive.
Fraser Cain: No. No, that’s not true. I was alive because I was born in 1971.
Pamela Gay: Oh, I thought you were younger than me.
Fraser Cain: No, I’m older than you.
Pamela Gay: Oh, man.
Fraser Cain: And the last person on the Moon was in 1972.
Pamela Gay: Okay. And I was born in ’73. So, you were pre-Apollo, and I’m post-Apollo.
Fraser Cain: I’m mid-Apollo.
Pamela Gay: Mid-Apollo. I’ll give you that, yeah.
Fraser Cain: Yeah, because I wasn’t there for the – and not that I remember anything. But I was at least in existence when this was happening. And so, I am, I don’t know, 46, maybe? So, it’s been that many years, give or take a couple, since human beings have set foot on the Moon.
And then, nothing except just dashed hopes and dreams for decade after decade where we all just got sadder and sadder, and nobody ever went back. And then, they took the vehicles that could take them back, and they smashed them.
Pamela Gay: And the degree to which no missions went back is more profound than I think a lot of people realize. So, you have all through the late ‘50s, all through the ‘60s people are talking about, “We’re gonna get to the Moon. We’re gonna get to the Moon.” And we actually tried and kind of, sort of made it in the end of the ‘50s. So, the Russians made it with their luna modules in ’59. We just kept screwing up until the ‘60s, and we eventually caught up. And then, it was like all through the ‘60s, “Moon, moon, moon, moon, moon. Keep going to the moon. More moon, more moon.”
‘70s came and it was like, “Yeah, okay, we’re kinda bored.” Planned patent certain style is finding new world to go to. And it was like this sudden cut-off valve got put into place where you have – In ’78, we tried to use it as a gravity assist, but does that count as going there? Not really. And then, we didn’t go back until ’98. Till ’98.
Fraser Cain: Yeah, but when you say “we,” are you saying the human beings set foot on the Moon in 1998, or traveled anywhere near it?
Pamela Gay: No, I’m saying that there was an orbiter, Lunar Prospector went back in ’98.
Fraser Cain: Yeah, like a robot.
Pamela Gay: Yeah. And so, just the fact that we went two decades. There are probably, if you look just right, there might even be like a few human beings out there who were born and became of age to drink in the time that were no robots at the Moon.
Fraser Cain: But I’m not so sad about the state of robotic exploration of the Moon. As you said, there was the Lunar Prospector in ’98. There was ESA Smart-1. And yeah, and they used this really cool ion drive to get there. The Chinese landed their cute, little rover on the Moon. And then, of course, there was the Lunar Reconnaissance Orbiter, which is there right now.
Pamela Gay: And I forgot, Clementine in ’94.
Fraser Cain: And Impactor.
Pamela Gay: Yeah. So, we had that in 2009. We had LROC impacting –
Fraser Cain: LCROSS.
Pamela Gay: Yes. I’m having a moment of wait, which is which? And I think all of us, at one point or another, have been subjected to the Kennedy speech of we do these things not because they’re easy, but because they’re hard. The speech that he gave at Rice University that triggered, along with the Cold War, all the financial and human resources that were necessary to make it to the Moon before that particular decade was out. And since then, it’s kind of been the in thing for presidents to promise to return us to the Moon. We had the Bushes do it. We had Trump do it. And we haven’t made it back yet.
Fraser Cain: It is really stunning to think that since the last Apollo mission, no human being has even left low Earth orbit. Absolutely, low Earth orbit has been fully exploited and people have gone around and around. And the fact that human beings have been continuously living on the International Space Station since its launch is a wonderful thing. But the fact that nobody has gone beyond low Earth orbit since then is very sad.
Pamela Gay: Yes.
Fraser Cain: When did people start to seriously, recently consider returning to the Moon? When did this start to happen?
Pamela Gay: We really saw a concerted effort in terms of putting the research, the funding, and the interdisciplinary science and engineering together in the mid-2000s with, initially, the formation of the NASA Lunar Science Institute out at Ames. And then, that got replaced with SSERVI, which is a small solar system object replacement that’s more inclusive depending on whether or not we’re going to go to the Moon, Mars, or a small rock. SSERVI does not include Mars itself, but it does include the moons of Mars. I don’t try and understand the politics on that.
But it’s through this – what are the scientific hurdles that we need to overcome, approach? And what are the scientific things we need to learn, approach – that I think we have the greatest possibility of figuring out how to get there in today’s much more limited budgets. As well as how to get there in a way that allows us to stay with a higher safety factor.
Fraser Cain: Okay. I think we should sort of set the stage a bit. After the Space Shuttle, they were gonna switch to the Constellation Program. And Bush said that we’re gonna go back to the Moon, and they were gonna build the Ares V and the Ares I. And the Ares V is gonna for cargo, and the Ares I was gonna be for people. And they were gonna dock up in space, and they were gonna go to the Moon, and then off to Mars.
And then, the Constellation Program was cancelled, and they switched to the Space Launch System. Space Launch System was gonna be used for going to asteroids, theoretically. And they built the Orion Crew Capsule Module, and it was gonna help build the Deep Space Gateway. Then last year, the Trump administration announced that they were gonna be canceling the Asteroid Program. Go. Here we are.
Pamela Gay: And now, we’re going back to the Moon again.
Fraser Cain: So, how’s this gonna work?
Pamela Gay: It depends on who you believe and who you listen to.
Fraser Cain: Only you is the only one I’m gonna believe and listen to right now.
Pamela Gay: So, I honestly suspect, due to the variations from administration to administrations on what NASA is authorized to do, that it may be SpaceX that gets us somewhere first. Because Elon Musk can pay for things.
Fraser Cain: Okay. But you’re adding variations. Can you – let’s go to what is currently the party line. NASA’s gonna do the job, what is the plan? And we’ll get into the variants in a second.
Pamela Gay: I need to put in the disclaimer; I am speaking as me, a human being, who is in my house, at home, using only equipment that I have personally paid for.
Fraser Cain: Right.
Pamela Gay: Okay. All those disclaimers in place.
Fraser Cain: If you want, I can say it. And that way you don’t get yourself into any trouble, and I’m just some silly Canadian.
Pamela Gay: No, no, it’s fine. So, the Space Launch System is a consortium of big aerospace, for lack of a better phrase, who are working on building a heavy launch vehicle that will be capable of launching giant things into outer space. And by giant things, this includes the Deep Space Station that you brought up that will be a jumping-off point to go beyond lunar orbit. It includes being able to get things to the Moon. And nominally, for getting things that are in space off and headed towards either an asteroid or Mars. And it’s the return that is trickier because Mars has a much larger gravity well. And how we get things back and how we survive the radiation of space are all unsolved problems, at this point.
Now at this point, Space Launch Systems has had significant timeline changes over the history of the mission. I believe they were already supposed to have launched by now.
Fraser Cain: Oh, yeah, yeah.
Pamela Gay: And they haven’t.
Fraser Cain: We should talk a bit about what the Space Launch System is going to be, right? So, it is a very traditional-looking rocket. It is a monster. The main engine of it is – it’s as if they took the Space Shuttle and sort of the configuration of the Space Shuttle –
Pamela Gay: Well, they did.
Fraser Cain: They really did, yeah. And so, they turned the Space Shuttle into just one big rocket. Because the main part, the main middle part of the Space Launch System is an oxygen, hydrogen – liquid oxygen, liquid hydrogen engine. And then, it has two solid rocket boosters like the Space Shuttle.
Pamela Gay: Which are the shuttles. They are.
Fraser Cain: It gets better. It has four of what are called these RS-25 engines. These are the Space Shuttle main engines. And in fact, they are recycled engines from the Space Shuttle. So, it’s gonna be launching with, essentially, the same technology as the solid rocket boosters. It’s gonna be using the same engines at the bottom of the main stage. And then, it’s gonna have different configurations on top. And this first configuration, the Block I, is gonna be capable of lifting off 70 metric tons. The later configuration, the Block II, Block IIB – it’s gonna have a stronger upper stage – it should be capable of doing 130 metric tons and maybe even 140. It should be able to lift off more than the Saturn V.
Pamela Gay: Yes. And so, where it starts to become a question is because this was originally slated for 2017, were now looking at 2020s, no earlier, and increasing costs along the line. One of the open questions that isn’t asked as part of the NASA Pathway, but I think a lot of NASA watchers and a lot of commercial space watchers ask is, if we see the Falcon Heavy, at a significantly lower cost point per pound, successfully taking off this year, what impact is that potentially going to have given that this all comes down to congressional funding?
Now, one of the reasons that Space Launch Systems initially got put together with this consortium was there was a great deal of lobbying, a great deal of concern about, essentially, Big Space no longer having the big contracts that they used to have. And so, things work in an open competition system. SLS was one of the many competitors for NASA contracts. This is a contract that they received, but they do have the lobbying arms going on as well. So, this is a very multifaceted, very complicated problem where the outcomes aren’t strictly determined by success and affordability.
Fraser Cain: Sort of the main purpose of this really was to put the workforce of the Space Shuttle to work on very similar hardware to adapt them to a vehicle that is capable of going into deep space. And so, the SLS really is the Space Shuttle, but designed for deep space and heavy lift – the Space Shuttle was a heavy-lift vehicle. Now, if everything goes well, we’re going to see sort of the first launch, as you said, maybe 2019, but I think you’re right, 2020.
Pamela Gay: It’s been pushed off to 2020, I think.
Fraser Cain: It’s gonna be a test launch with the Orion Crew Capsule. I don’t think EM-1 is gonna have humans on board.
Pamela Gay: No.
Fraser Cain: Then you’re gonna have, I think, the Europa Clippers coming after that.
Pamela Gay: 2022 if all goes well.
Fraser Cain: And then, they’re gonna build the Deep Space Gateway. So, what is – and I think there’s four launches to build the Deep Space Gateway. So, what’s that gonna be about?
Pamela Gay: So, I believe this is a Lockheed project where they’re looking to build a platform that is several different modules plugged together. And then, you can use this as either a jumping-off point to get to the surface of the Moon, or because you’re really out of the gravity well for the most part both the Earth and the Moon, this is closer to the Moon than to the Earth. You’re ready to build things there and hop off to go into, well, further space.
Fraser Cain: And so, I think you’re looking at construction of the Deep Space Gateway into sort of the mid-2020s. And if that all happens, then we may then start to see missions from the Deep Space Gateway down to the surface of the Moon following that.
Pamela Gay: Yes. And the question starts to become – So, the Deep Space Gateway is something that is the same consortium of people that are behind the International Space Stations. So, this is – know how that group of collaborators, that group of funders for – Well, you have to have money. And go out into what’s called sisal inner space – this area between the Earth and the Moon that has this completely different gravity well that you’re dealing with – and take off from there.
Now, with this group of people, something’s gonna have to happen. But it’s still very much at the concept stage. It’s still very much at the proposal stage. And so, it’s going to be interesting to see what happens. It was a study that came in in November 2017 that helped set forward the guidance for how we’re gonna do this. And awards are just starting to get made.
Fraser Cain: One of the things that’s really interesting. Late last year, the Russians announced that they were gonna be contributing to the Deep Space Gateway. So, they’re gonna be contributing three modules, at least, as well as the entire docking system to the Deep Space Gateway. And the Canadians announced that they’re gonna be supplying, potentially, a solar sail and, obviously, some kind of arm. But a solar sail that would serve for station keeping, which is a new technology that’s kind of never been tested, which is really interesting. Because right now, station keeping requires propellent and propellent is a finite thing.
Pamela Gay: And it has weight.
Fraser Cain: Yeah. So, if you can develop a solar sail-based station keeping system, then you pretty much don’t need to carry any propellent to do it. So, this has been kind of tested out in the past. But this is gonna be in theory. But this is all still, again, all in theory. If all goes well and nothing gets delayed, then we’re gonna see the Space Launch System launch in the next couple of years. It’s gonna help build the Deep Space Gateway, and then astronauts will fly the Deep Space Gateway, spend time there, and then they’ll start going down to the Moon. Right on. Now, let’s follow some of these alternate pathways on ways that the Moon may come together.
Pamela Gay: So, we have Elon Musk. He’s the wild card in a lot of this. He’s very much the much more stable Howard Hughes of the modern era where he has the diversified financial portfolio, the diversified creativity. And this allows him to just get stuff done. And we’re looking at next week, if we’re lucky, they’re gonna have the first test of the Falcon Heavy. And they kind of don’t expect this one to go well. And what I appreciate is, with SpaceX, they allow for failure. We look at the Space Launch System, and their very fist one plans to send an Orion Capsule and six CubeSats on a meaningful orbit. They can’t afford to make mistakes. Elon is launching his personal Tesla.
Fraser Cain: I know, I know, I know. It’s so funny. It’s so weird. I feel like we’re dreaming right now that a private individual is running a company that’s gonna launch a car to Mars.
Pamela Gay: To the orbit of Mars. It’s not contaminating Mars. It’s the proximity of someplace Mars has the potential to be.
Fraser Cain: So, if they pull this off, the Falcon Heavy costs $90 million a launch. If you want to buy payload on a Falcon Heavy, you only have to spend $90 million. SLS is gonna be half a billion to a billion dollars per launch. You can tell I just did an episode about this. Each individual RS-25 engine costs $60 million. And the Space Shuttle, they will reuse. They’re all getting thrown away with these launches. So, needless to say, the cost [inaudible] [00:21:17].
Now, the Falcon Heavy is only going to launch 45 metric tons, not 70 metric tons. So, it’s not as heavy as the SLS.
Pamela Gay: But you can assemble things in orbit. Think about how much more cost-effective it will become to have two of those 90 million launches that gets you the same tonnage, essentially, once you have some drive systems added as that one SLS. You don’t have to wait as long. The SLSs are all accounted for through 2033. There are no extra SLSs that are hanging around going, “Hey, I’m available for commercial use.”
Falcon Heavys, they’re just making these things as they need them. And so, we don’t know yet what’s going to be available and what’s not. But because of this potential flexibility and the lower cost, you just change the way that you’re thinking. And we go to a model of we know how to dock things together in space, otherwise our astronauts would starve to death. Let’s just robotically dock things together and move forward with things that launch in two pieces instead of one.
Fraser Cain: Yup. So, the Falcon Heavy has been delayed many years, many years. And it has turned out to be a more complicated and more expensive and more risky undertaking than SpaceX had ever planned. And at the same time, they are now, hopefully, gonna launch this. And I’m sure NASA is looking at this, but until they get guarantees from SpaceX that, “Oh, yes, absolutely. We are as safe as you require. We can handle the payloads that you want. The price is cheap. It’s all good.” Then NASA’s only reasonable direction to go is what they were already planning until someone proves them better. Because a lot of the time, SpaceX is talk, right?
Pamela Gay: So, there’s also this other problem. So, I don’t know about you, but there’s been more than one time I’ve been playing a video game, and I’m like, “Dang it, I’m gonna just spend 15 bucks to speed up this part of the game that’s driving me crazy and pay for the booster packs.” And then, I feel financially obligated to keep playing the game even if it’s no longer fun.
Fraser Cain: Sounds like the sunk cost fallacy.
Pamela Gay: It’s the sunk cost fallacy. And if you start looking at the Space Launch System, you have the Orion Capsules, which are not compatible with the Falcon Heavys. You have all of the other vehicles that have been built from the folks working on trying to plan lunar rovers to everything else, all built and adapted, at least in CAD software, specific for the Space Launch System. How easy or hard it’s going to be to say, okay, so SLS is still slow, it’s still behind the gate, it’s not getting here any faster. We now have the Falcon Heavy, do we reconfigure? Do buy into the dragon? Do we continue parallel development so that we don’t have, like we had before, only on path to space?
Fraser Cain: Yeah. And I think that’s the key, right? Is that we suddenly have multiple paths to space. That up until a decade ago or so, all we could do was wonder why NASA hadn’t sent humans back to the Moon? There were no real plans to go to Mars. And now, what you’ve got is you’ve got not only NASA, but you’ve got, potentially, private individuals like SpaceX, like what Jeff Bezos is doing with Blue Origin. And then, you’ve got other interesting things like these collaborations between, I think, man, I feel like it’s Lockheed Martin and Bigelow to send an inflatable habitat to the Moon.
The Chinese have built their own simulation moon base in China, and people have been testing out in that. And they’ve made it really clear that it is their plans to send humans to the Moon. And they’re sending rovers and spacecraft and missions to lunar orbit. So, that’s in their works, as well. So, I think whether or not it’s NASA, whether it’s SpaceX, I think we are now inevitably on this pathway that humans are gonna be making it to the Moon.
Pamela Gay: And I have to add, I’m pretty sure China’s actually going to get there first.
Fraser Cain: Whoa. You think so?
Pamela Gay: I’m throwing that in. And I do think so. They have been quietly doing great things with their space program. Due to various congressional restrictions, we are not, here in the United States, allowed to collaborate with the Chinese. And they’re not allowed on the International Space Station. The Russians are, but the Chinese aren’t.
Fraser Cain: Now, when you say “great things,” you’re using that in a Voldemort sense, right? Great and terrible things, but great things.
Pamela Gay: No, no. They successfully had a space station. Admittedly, the first one kind of fell out of the sky.
Fraser Cain: Well, it’s going to –
Pamela Gay: Well, yes, it’s falling, actively, out of the sky. But they’ve been quietly doing human launches. They’ve been quietly building infrastructure in space. They’ve been quietly doing solid lunar exploration. They’re building their tech. And this slow and steady turtle approach as opposed to the jack rabbiting you see in several other parts of the world – I remember that Aesop’s fairytale. And so, part of me really thinks that as the rest of us are falling prey to our election cycle and the funding cycle that goes with it, for better or worse, their longer-term regime is going to get them there first as, perhaps, a wake-up call where they quietly land one day, and the rest of the world wakes up.
Fraser Cain: And then, I think the last piece of hardware that I think we should mention is the BFR, which is gonna be coming down the pike from SpaceX, the big, freaking rocket, the big fabulous rocket, the big –
Pamela Gay: Phenomenal.
Fraser Cain: No, that’s the wrong letter. But yeah, fantastic rocket. Anyway, it something. As part of the presentation, the BFR will just as one of the things it can kinda just do is land on the Moon and return to Earth, all on its own.
Pamela Gay: All because.
Fraser Cain: And all reusable. So, if and when the BFR starts to fly, then we are in an entirely new game. It is not the way these missions were planned. It is a totally new field. And I think we need to take everything, the entire rulebook, throw it all out and start from scratch. Because now, the capability and the distance to get – the capacity to get to space and to go to various destinations is at a phenomenally cheaper price is totally new.
Pamela Gay: And what I really want to see, right now, is someone to sit down and do a comparative study of this company says they’re going to complete things by this date, and they’re always 10 percent over. And this company is always 30 percent over. And this country is always 10 percent over. And this country is always – they just don’t even get there. Yes, Elon Musk is always behind the bat. But so far, he’s getting stuff done. I don’t think he was on many of our radars back when the Ansari XPRIZE was won by space composites. And I was expecting Virgin Galactic to be launching tourists by now.
Fraser Cain: Yes.
Pamela Gay: And here we are.
Fraser Cain: Yeah, with rockets that land. It’s crazy.
Pamela Gay: Yeah.
Fraser Cain: All right. So, let’s just have some fun.
Pamela Gay: Yes.
Fraser Cain: And then we’ll wrap up this episode. So, place your bets, who and when?
Pamela Gay: China, 2025.
Fraser Cain: Okay, good one. That’s good. Okay, I’m gonna say NASA via a Falcon Heavy in 2028. Wow. Why are you the enthusiastic, optimistic one? Weird. Anyway, I clearly have been too deep into this for a little while.
Pamela Gay: When we started this show, I said Russia by 2020. So, I’m not to be believed.
Fraser Cain: Oh, someone dig that up. That would be awesome. All right, thanks, Pamela. We’ll talk to you next week.
Pamela Gay: Bye-bye.
Male Speaker: Thank you for listening to Astronomy Cast. A non-profit resource provided by Astrosphere New Media Association, Fraser Cain, and Dr. Pamela Gay. You can find show notes and transcripts for every episode at astronomycast.com. You can email us at info@astronomycast.com, tweet us @AstronomyCast, like us on Facebook, or circle us on Google+.
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[End of Audio]
Duration: 31 minutes
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