Return to the Moon Lunar Station
After the launch vehicle and upper stage for the Return to the Moon program are selected, the next step in building an affordable Earth-Moon space transportation system will be to build a Return to the Moon Lunar Station in low lunar orbit. Like the currently planned Gateway Space Station, this Return to the Moon Lunar Station will need the same first two modules, the Power and Propulsion Element (PPE) and the Minimum Habitation Module (MHM). In addition, the Return to the Moon Lunar Station will also need the already planned Gateway Logistics Module. The Gateway Logistics Module is the module that will refuel the lunar landers for going to the Moon and the Orion spacecraft for its return trip to Earth. So other than including the Gateway Logistics Module from the beginning and placing the station in a low lunar orbit, the Return to the Moon Lunar Station will be made from the same components that are already being designed and built for the Gateway Space Station.
As currently planned, the Gateway Space Station is to be placed in a halo orbit around the Earth-Moon L2 Lagrange point. The primary reason for choosing this location is because it takes less velocity change to go from the Lunar Transfer Orbit to the L2 halo orbit than it takes to go to Low Lunar Orbit. The velocity change required to go from Lunar Transfer Orbit to the L2 Halo orbit is 420 m/s. The velocity change required to go from Luna Transfer Orbit to Low Lunar Orbit is 820 m/s. This reduction in velocity makes it possible for the Orion spacecraft to go to the L2 halo orbit and return to the Earth without refueling. The disadvantage to this is that it takes 730 m/s of velocity change to go from the L2 Halo orbit to low lunar orbit. This increase in velocity is added to the lunar lander both when it goes down to the Moon and when it returns to the L2 Halo orbit. The additional propellant required to do this dramatically increases the size, complexity, and cost of the lunar lander. By comparison, lunar landers designed to operate from low lunar orbit are a fraction of the size and cost. These differences will be discussed in more detail in “Return to the Moon Lunar Landers.”
Selecting the most cost effective orbit for the lunar orbiting space station will be the second most important decision for the Return to the Moon program due to its impact on the size and cost of the lunar lander, the size and cost of the launch vehicle needed to send the lunar lander out to the Moon, and the amount of propellant that will need to be sent to the Moon for its on-going operation. The total difference in cost between the lunar landers designed for these two orbits is huge. The selected space station orbit will also have a significant impact on the cost of lifting lunar water, lunar propellant, lunar oxygen, lunar food, and lunar regolith for shielding, to the station once the lunar base starts to produce these items in quantity. As stated before, designing for low cost is crucial if the Return to the Moon program is to become a Return to Stay program. It will also have a very large impact on the cost of going to Mars once we are ready to do that.
Ad Astra! (To the Stars)
Note: For those of you who are new to this website, this site is about making spaceflight affordable to everyone so we can finally start building the most incredible civilization the world has ever seen. A civilization that will include planets, asteroids, moons, space-based industries, and space colonies throughout the solar system. For those of you who are fans of space exploration but are new to the subject, the best way to read this site is to start at the beginning and read through to the most current article. If you are already familiar with the subject then feel free to jump around.
Index of Articles
- Opening the High Frontier
- Skyhook, a Journey to Orbit and Beyond
- In the Beginning . . .
- Why do Rockets Cost so Much?
- Combination Launch Systems
- It’s All About Speed!
- Visions of the Future
- The Call of an Unlimited Future
- Combination Launch Systems, part 2
- Outward Bound: Beyond Low Earth Orbit
- and someday . . . Starships!
- Mars: how to get there
- Outpost Space Stations
- Dreams of Space
- The Moon or Mars?
- Skyhooks and Space Elevators
- Stratolaunch and the X-15
- Starship Congress
- Making Spaceflight Affordable
- How a Combination Launch System Works
- Starship Conference 2017
- New Worlds Conference 2017
- Opening the High Frontier
- Building a Spacefaring Civilization
- Space Exploration and the Future
- Guiding Vision
- Return to the Moon to Stay
- Return to the Moon Launch Vehicle
- Return to the Moon Lunar Station
- Return to the Moon Lunar Landers
- Return to the Moon Space Tug
- Skyhooks, Space Elevators and Space Exploration
- Vertical Accelerator Launch Tower
- Combination launch system
- Opening the High Frontier (the Book)