The Mighty XEUS

ACES derived XEUS DTAL lunar crew lander (Credit: ULA)

The United Launch Alliance's (ULA) reusable XEUS vehicle would use ACES cryotanks capable of storing up to 68 tonnes of LOX/LH2 propellant. Filling up with liquid hydrogen and oxygen at a LOX/LH2 propellant producing water depot located at EML1, the XEUS could be used to transports astronauts, round trip,  between EML1 and the surface of the Moon.

The XEUS  could also be used to transport astronauts between propellant depots located at  LEO and EML1 or EML2. 



 Beyond cis-lunar space, the XEUS vehicle could be used to access the surfaces of Mercury, asteroids in the asteroid belt such as Ceres, Vesta, and Psyche,  Jupiter's moon, Callisto,  and also the moons of Mars, Phobos and Deimos.

As a cargo transport operating out of EML1, the XEUS could deliver more than 50 tonnes of cargo to the lunar surface or transport more than 50 tonnes of water extracted from the lunar ice back to propellant producing water depots located at EML1 or EML2. 

Deployed into Earth orbit by a  Vulcan/ACES 68 launch vehicle in the early 2020s, the XEUS could give NASA, the DOD, other government space agencies, and even space tourist easy access to the surface of the Moon and back while helping to give humans access to other regions of the solar system.

Marcel F. Williams


Links and References

A Commercially Based Lunar Architecture

Robust Lunar Exploration Using an Efficient LunarLander Derived from Existing Upper Stages

ACES Stage Concept: Higher Performance, New Capabilities, at a Lower Recurring Cost

Efficient Utilization of the Space Launch System in the Age of Propellant DepotsThe ULA's Future ACES Upper Stage Technology