# Why is the US building a Lunar Orbital Platform-Gateway (LOP-G)?

An excerpt taken from the Wikipedia page on LOP-G says space-experts have criticized it:

The Deep Space Gateway has received criticisms [...] for lacking a proper scientific goal.

Former NASA Astronaut Terry Virts [wrote] that the Deep Space Gateway would "shackle human exploration, not enable it" [...] and that he cannot envision a new technology that would be developed or validated by building another modular space station.

Mars Society founder Robert Zubrin [...] called the Deep Space Gateway "NASA's worst plan yet" in an article on the National Review. Robert went on to say "We do not need a lunar-orbiting station to go to the Moon. We do not need such a station to go to Mars. We do not need it to go to near-Earth asteroids. We do not need it to go anywhere. Robert also stated that "If the goal is to build a Moon base, it should be built on the surface of the Moon."

Retired aerospace engineer Gerald Black stated that the "LOP-G is useless for supporting human return to the lunar surface and a lunar base." He added that it is not even planned to be used as a rocket fuel depot and that stopping at LOP-G on the way to or from the Moon would serve no useful purpose and it would actually waste rocket fuel.

Pei Zhaoyu, deputy director of the Lunar Exploration and Space Program Center of the China National Space Administration, concludes that, from a cost-benefit standpoint, the gateway would have "lost cost-effectiveness." Also, Pei said the Chinese plan to focus on a research station on the surface.

My question to the community is, what could a rectilinear halo orbit around the moon potentially gain for us, especially if refueling isn't planned to occur at that location? It's clearly not being used as a Mars staging point if there's no fuel depot, and it seems to not have much utility other than studying Lunar orbit, and possibly studying the lunar surface...

• Does anyone have more in-depth plans on what the actual mission is?
• Why, as the Chinese stated, do we not build something on the surface?
• What, if anything, can we learn that the Apollo programs missed and that the James-Webb Telescope might miss as well?
• Same reason we are building SLS. Jobs in certain states. It is really not that good an idea, and I do not expect it to actually happen. Mostly because its actual targetted date is after SpaceX is likely to be running regular Mars missions. – geoffc Aug 16 '18 at 13:50
• I've replaced "Why are we..." with something more neutral. I still remember the 1958 Mad Magazine satire suggesting one shouldn't make assumptions. Musical reference as well. – uhoh Aug 16 '18 at 14:31
• @uhoh not a bad idea to be honest, especially because the question itself references other nations as well. – Magic Octopus Urn Aug 16 '18 at 15:26
• it isn't the US @uhoh, "The development is led by the International Space Station partners: ESA, NASA, Roscosmos, JAXA and CSA for construction in the 2020s" – JCRM Aug 16 '18 at 20:26
• It won't happen, and Spacex won't be running regular Mars missions either. We are deeply screwed, I'm afraid. – Organic Marble Aug 17 '18 at 3:52

A zillion years ago I was at a meeting where large projects were discussed and attempted to be justified. A slide was shown listing say five reasons why project such-and-such was absolutely vital and the speaker enthusiastically forwarded each reason in turn.

The one response was "If you had one good reason you wouldn't need five.

Ultimately it wasn't funded.

My other answer reminds me of this story.

note: I'm presenting the following position while neither advocating nor criticizing it. Until the time that we live in Gene Roddenberry's envisioned future, there's nothing wrong or dirty about economic growth.

The Ars Technica article NASA says it’s building a gateway to the Moon—critics say it’s just a gate is really worth reading.

It contains a similar zinger-like insight in my opinion:

the Gateway will be a place where rockets can go.

This has not left much oxygen in the room for dissenters—publicly, at least. However, a few critics persist, and they raise valid questions about the lunar Gateway. Robert Zubrin, a high-profile aerospace engineer outside of NASA’s policymaking process, has emerged as a chief antagonist.

It is the next giant leap into quicksand,” Zubrin argued (YouTube link) during a recent meeting of The Mars Society. “If you wanted to send people to the Moon or Mars, would you take some of your money to build a lunar orbit space station on the way? You would not.” (emphasis added)

Zubrin and others argue that the Gateway exists not to smooth NASA’s way to the Moon or Mars, but rather to provide a destination for the agency’s expensive rocket, the Space Launch System, and Orion spacecraft. These vehicles, built for NASA by large aerospace firms with hundreds of subcontractors around the country, cannot presently go to the Moon or Mars. Combined, they’re just not powerful enough. NASA has struggled for the better part of a decade to find something for them to do. And after wandering in the wilderness, agency leaders finally settled on the Gateway concept.

• Kind of a disheartening answer, but a good polarization to the other one you provided. “This is not a purpose-driven program, this is a vendor-driven program. Imagine running your business to please your vendors.” Is a very solid analogy that changes the whole perspective. – Magic Octopus Urn Sep 6 '18 at 18:26
• Echos of Space Shuttle? – Anthony X May 15 at 1:25

Let's examine what Jim Bridenstine, current director of NASA and previous member of the Rocket Racing League (1, 2, 3) says.

NASA Administrator Jim Bridenstine Explains the Lunar Gateway is a recording of director Bridenstine in YouTube, described as

Published on Aug 7, 2018

NASA's new administrator spoke with reporters after a two-day trip to Kennedy Space Center about the agency's plans for a lunar gateway.

I don't have a date for the talk yet, presumably it's recent.

A quick summary:

• "Ultimately the gateway, the first gateway is a technology demonstrator, and it’s going to retire risk, that’s what it’s for."

• "The second gateway that’s going to go to the Moon, will be a deep space transport. That will be our capability to get to Mars. That’s the purpose of the gateway."

• "what the Gateway represents is that critical infrastructure to where all of our partners can, in essence, have access to the surface of the moon, and to orbit around the moon and ultimately go back and forth from the Earth to the Moon."

• "what the Gateway gives us (to your question) what the Gateway gives us more access to more parts of the Moon than ever before. And it gives us long-term sustainability at the Moon that we’ve never had before."

This is my own attempt at transcription, starting at about 01:50.

Remember that this is likely an impromptu summary and review of key points to the press, rather than a prepared public speech, so it appears a little choppy when written out as text.

There are more commercial partners than any point in history.

So all of this enables us to do more than ever before, and what the Gateway represents is that critical infrastructure to where all of our partners can, in essence, have access to the surface of the moon, and to orbit around the moon and ultimately go back and forth from the Earth to the Moon.

So the Gateway is that critical piece of infrastructure. We want it to be an open architecture. We want all of the interfaces to be published whether it’s power, whether it’s docking, we want it to be absolutely open so that international and commercial can use it and take advantage of it and we want more access to more parts of the moon than ever before.

So what the Gateway gives us (to your question) what the Gateway gives us more access to more parts of the Moon than ever before. And it gives us long-term sustainability at the Moon that we’ve never had before.

It’s also true, because it’s solar-electric propulsion it’s not as big as the international space station. But with solar-electric propulsion, it’s not just going to be in an orbit around the moon, it’s going to actually go to L2 and L1, and give more access to more parts of the moon than ever before.

So you think about from 1969 when we first went to the Moon, all the way up until 2008. We believe that the Moon, at least a lot of people believe at the moon, was bone dry, because our access to the Moon, we have six missions, it was all in the equatorial region, and in all those years we believed that the Moon was bone dry.

Well in 2008 the Indian Space Agency made a discovery. In 2009 NASA doubled-down on that discovery, and now we know that there are hundreds of billions of tons of water ice on the surface of the Moon at the poles. Well that water ice represents a number of things, chief among them is life support. It’s water to drink, it’s air to breathe, hydrogen and oxygen, even more importantly, or at least as importantly, it represents fuel.

When you crack water into its component parts hydrogen and oxygen and you put it in cryogenic form, that’s the same propulsion as the space shuttles.

So water discovered on the surface of the Moon should transform how we think about our activities in space. And so in my view, the gateway represents our ability to learn more about the Moon than we’ve ever known, and we need to go to more parts of the Moon than we’ve been able to get to before. We do that with gateway as critical infrastructure, then we have commercial and international partners and our own landers back and forth between the gateway and the Moon all in a reusable way for a sustainable architecture.

Ultimately the gateway, the first gateway is a technology demonstrator, and it’s going to retire risk, that’s what it’s for. The second gateway that’s going to go to the Moon, will be a deep space transport. That will be our capability to get to Mars. That’s the purpose of the gateway. So we’re going to be able to get to more parts of the Moon than we’ve ever been able to get to before; ultimately everything is going to be reusable; gateway is the critical piece of infrastructure to make that possible, and it will ultimately be our deep space transport.

So the gateway is important. And of course it’s going to be important for Kennedy as much as NASA.

I would look for the power propulsion to launch sometime around 2022. And that would be the first piece, habitation shortly thereafter, maybe 2023, (or 2024).

• – uhoh Aug 17 '18 at 3:31

Because the Lunar gateway develops technologies for a Mars gateway; it's easier to build them in space than to construct them on the ground; teleoperating robotics (which reduces contamination) is easier from orbit than from Earth.

Building in orbit around the moon is much cheaper than doing so around Mars, and allows for frequent resupply while the technologies to allow a far more self-sustaining environment are developed. It also allows for a return to Earth in days in the event of a catastrophic system failure while lessons are learned.

While this work could be done in earth orbit, it is arguable a new orbital facility would be needed as systems designed in the 70s just can't be upgraded to the standard needed. Even if the ISS can be handed off to commercial entities, running two space stations around the same planet gains nothing compared to the research opportunities running a space lab around the Moon.

• So, you're saying we're putting a Gateway into lunar orbit to move it to Mars later...? Or you're saying we're doing this to test how we'd do it around Mars? If so I wouldn't say this answer is complete without explaining what we stand to gain: I want to know how that case study differs significantly from the ISS or anything we've already done; and how it helps build an orbital gateway around Mars. – Magic Octopus Urn Aug 16 '18 at 21:11
• what in my answer suggest it would be moved @MagicOctopusUrn? – JCRM Aug 16 '18 at 21:56
• Your answer still has no information about why building a space lab around the moon has anything to do with building a space lab around Mars... So I assumed a link between the two topics existed somewhere and guessed what it was...? I still don't understand how building a space lab around the moon will teach us anything about building one around Mars that the ISS didn't, from this answer. In the near future the ISS will be decommissioned regardless, so... there wouldn't be 2 labs ever, if we're testing new tech... seems Earth orbit still would make far more sense... – Magic Octopus Urn Aug 16 '18 at 22:32
• Why put it around the moon when we could deorbit/decommission the ISS in favor of a new space station in LEO (to test the new tech) where access isn't a significant increase in the delta-V of what it is currently to reach it? – Magic Octopus Urn Aug 16 '18 at 22:36
• If I may add, the LOPG will also be in a special Halo orbit which will bring a number of great opportunities to land on the Moon, but also allow us to better learn how to do operations in highly dynamical environments. Although a Mars bound trajectory isn't as dynamical, it has a number of very critical points in its trajectory and the added complexity of distance (ie comms time). So knowing how to do ops in a highly dynamical environment allows us to much better handle simpler environments with the added comms delay. – ChrisR Aug 17 '18 at 0:38