The Starship Lunar Lander Q-and-A with the AI chatbot

Updated 5-24-23: Detachable nose cone

This is a video of the idea of making the nose cone of the Starship detachable, and using it to land on the moon. It is the idea I expressed in the previous update.

This video doesn't discuss making the nose cone into aluminum as opposed to stainless steel.

Here's the video, which is slated to start at about 4:20 into it, and which describes the idea. It's from the Terran Space Academy channel...

Updated, 5/24/23:

After a lot of trial and mostly error, I think I've finally figured out how the Human Landing System ( SpaceX's Starship Lunar Version) will work. It would seem to be a bit dicey, though. It may be better if the cargo is reduced by a substantial fraction in order to give plenty of safety margin.

Then why not do further reductions? It probably won't happen like this, but the Starship Lunar Version won't be going back down to Earth anyway. Therefore, why not do a few more things to it in order to reduce mass? The raptor engines are almost completely useless in the lunar configuration anyway, so why not divide the ship into two pieces, and ditch the raptor engines in orbit?  Also, the Super Dracos can be used for all of the maneuvers in cis-lunar space. The Super Dracos are necessary anyway, since the raptors will dig a hole into the surface where the ship is attempting to land.

Another radical change would be to make the ship aluminum instead of stainless steel. An all aluminum ship will be more costly to build, of course. It would be more of a "one off" construction, so this isn't likely to happen. But if you're going to ditch the raptors for the lunar landing, then why not go a little further?  Another possibility would be to keep the configuration the same as far as the raptor part of the Starship, but aluminum in the cargo and crew areas.

Aluminum is much less dense than stainless steel, so substantial savings can be achieved. Let's say the 140 ton empty weight could be reduced to say 35 tons. In such a scenario, it would be a much more capable system for its mission. Also, the refueling could be reduced to just one trip, if that much. For instance, the weight savings could go into the added fuel needed for the Super Dracos.

I haven't run the numbers on that, so it is pretty speculative at this point.

The problem is that an empty Starship weighs 140 tons. All of this weight gets dragged around, and it really adds to the mass needed to land on the moon, and to return to lunar orbit. A much lighter ship means a lot less fuel would be needed. It could still be quite a capable system, which could deliver an impressive amount of cargo to the lunar surface. Also, there is some risk to the mission of using cryogenics for a mission. The Super Dracos use hypergolics, which would not need cryogenics.

The downsides are added costs and some added time to develop a new system.

 5-23-23, Update:

I suspect the numbers given by the chatbot are incorrect.  If not, then my calculations are wrong.

the original post follows...

The Starship Lunar Lander Q-and-A with the AI chatbot

A speculation would have it that the Starship will use the Super Draco thrusters to land softly on the moon, as opposed to the too powerful raptor engines. The raptors will dig a big hole in the ground---not good.

There will need to be several refueling launches to fill up the Starship for its journey to the moon. It will need just about all of it to land on the moon, and to deliver payload. Up to 100 tons of payload.


One caveat here is whether or not I performed the calculations accurately, or whether the chatbot gave correct answers.

The following chatbot session was to derive the info needed to plug into the rocket equation in order to see if there will be enough fuel to make the trip. The answer appears to be yes.

bno blog Q: How much thrust does a super draco rocket engine generate?


Bing AI Chatbot A:

Each SuperDraco engine produces a maximum thrust of 16,400 pounds-force (73 kN) in vacuum. However, the engines are throttled to 15,325 pounds-force (68.2 kN) of thrust to maintain vehicle stability.


bno blog Q: How much fuel can the SpaceX starship carry in it's fuel tanks?

Bing AI Chatbot A:
According to Wikipedia, the SpaceX Starship has a total propellant capacity of 1,200 t (2,600,000 lb) across its main tanks and header tanks. The header tanks are better insulated due to their position and are reserved for use to flip and land the spacecraft following reentry.


bno blog Q: What is the delta v for the Starship from low earth orbit to the lunar surface?

Bing AI Chatbot A:
According to Space Exploration Stack Exchange, the delta-v required to get from a lunar transfer orbit to a near rectilinear halo orbit is about 1.5 km/s. The delta-v required to get from low Earth orbit (LEO) to the Moon is about 3.2 km/s. Therefore, the delta-v required for the Starship from LEO to the lunar surface would be approximately 4.7 km/s.

bno blog Q:In order for the Starship to go from the lunar surface to a near rectilinear halo orbit requires how much delta v?

Bing AI Chatbot A:
According to Wikipedia, the Lunar Gateway space station is planned to be deployed in a highly elliptical seven-day near-rectilinear halo orbit (NRHO) around the Moon. Spacecraft launched from Earth would perform a powered flyby of the Moon followed by a NRHO orbit insertion burn to dock with the Gateway as it approaches the apoapsis point of its orbit. The delta-v required for this maneuver is about 1.1 km/s.

....discussion ends...