NASA had a live teleconference today to talk about the coming Artemis III mission to prepare for the next moon landing. It's all in a slightly over two hour video on YouTube. Ars Technica has a good summary, and since most of this info has been covered there, and I've brought it here, their summary is easy to read.
An important thing to put out early is that NASA is still planning to launch Artemis III by next summer, but they don't get more specific than that. This is a demonstration mission in near Earth orbit involving docking with both Blue Moon and Starship. The lunar landing mission will be "in 2028" but nothing more specific about how long after Artemis III they think they'll need to prepare. Let's say III launches in July of '27; will IV be able to roll in January or February of '28, or will it be in November or December?
“This is an achievable path we are on right now,” NASA Administrator Jared Isaacman said. “We have the mandate, we have the resources, and the support from our stakeholders to be able to execute, and that’s what we intend to do.”
It is commendable that Isaacman and his leadership have taken a hard look every element of the Artemis Program and sought to make changes where they can help the lunar lander companies execute and accelerate their plans. But can they hold to those dates?
It's important to remember that among this mission's objectives is to rendezvous and dock with both Starship and Blue Moon, so there are really two complete mission plans at play and it's only fair to present both of those here.
First, SpaceX. You'll recall that the starting point before Jared Isaccman and when the current version of Artemis involved a lunar-orbiting space station called the Lunar Gateway. When SpaceX won the Human Landing System contract, that was a requirement. Isaccman ditched Lunar Gateway earlier this year, and SpaceX has adapted their HLS to the current requirements. They will fuel a Starship lunar lander in low-Earth orbit before docking with Orion in high-Earth orbit. For the landing mission, the crew will fly to the Moon inside Orion before two of four astronauts transfer into Starship for a landing on the Moon.
The SpaceX version of Artemis III's requirements
Image credit: NASA
This week, the Rumor Mill got excited when a NASA Safety Panel reported that the current number of Starship tanker launches that will be required is “about 22.” As always, that rumor went around world several times before Elon Musk heard of it and said that estimate was wrong, and the actual number will be six to eight.
I think it's fair to say that nobody really knows because of the vast amount of unknowns to consider. Jared Isaacman said essentially he didn't accept Musk's statement and thought it meant maybe six to eight "some day." So say it'll be somewhere between six and 22.
Blue Origin's version of Artemis III's requirements
Under the concept of operations released Friday, a New Glenn rocket (this could be an expendable version of the smaller 7×2 variant of New Glenn, or a reusable 9×4 rocket) would launch three “transfer stages” to low-Earth orbit. These transfer stages are modeled after the Blue Moon Mark 1 lander, but have some significant modifications.
Then New Glenn would launch the Blue Moon Mark 2 lander into orbit, where it would rendezvous with the transfer stages that will push the stack to the Moon. This is not new information, as Ars first reported this architecture in March. However, NASA did reveal a potentially significant change on Friday.
The chart shared by NASA showed Orion docking with the Blue Moon lander in an elliptical lunar orbit, approximately 8,500 km above the Moon’s surface. However NASA is also working to have the option of docking with Orion in low-Lunar orbit.
The advantage of the low-Lunar orbit is it could significantly reduce the propellant needed by Blue Moon to bring astronauts down to the lunar surface and back up. As always, "engineering is the art of compromise" and the mass of propellant required to handle the higher orbit could be used elsewhere. Plus the different orbit could offer mission flexibility that's not available in the 8,500 km orbit.
There's more to this conference than easily fits in this space. One of those is that since the SLS (Space Launch System) was designed, Artemis has been hampered by not having an upper stage (to include the Orion service module) that's got enough thrust to be useful. NASA announced they're working with ULA to specify and develop a different version of the Centaur Upper Stage of SLS. The concept is an upper stage replacement that would allow Orion to reach low-lunar orbit.
In fewer words, that's spending millions to fix a problem that SLS has had for as long as it has existed. For a rocket system that's already obscenely expensive to launch. As I've said so enough that I'm bored with it, a single SLS launch costs $4 billion. A Falcon Heavy costs a small percentage of that. It has less payload capacity than the SLS but not much less, so launch TWO modified Falcon Heavies for less than 10% of the cost of an SLS launch and get more payload to the moon.
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