MOSCOW, March 15. /TASS/. Researchers from Russia’s Skoltech hi-tech hub and the Massachusetts Institute of Technology offered the optimal module design for delivering astronauts from a lunar orbiter to the Moon’s surface and back. The research paper was published in the journal Acta Astronautica, the Skoltech press office reported on Monday.

In 2017, the United States launched the Artemis program, which aims to bring "the first woman and next man" to the Moon's South Pole by 2024. The Artemis program stipulates using a new orbital platform called the Lunar Gateway as a permanent space station to allow reusable modules to deliver astronauts to the Moon. Currently, private companies contracted by NASA are conducting research into new reusable landing modules for this mission, the press office said.

In their new research, the scientists analyzed 39 versions of future human lunar landers, including a comparative analysis of the most promising options in terms of the project’s cost, it said.

"With all the assumptions in the paper considered, a reusable one-stage module running on liquid oxygen and liquid hydrogen (LOX/LH2) is the ‘indisputable’ leader among the solutions for short-term lunar missions," the statement says.

The researchers used a comprehensive approach towards assessing alternative concepts of lunar landing modules and analyzed a large number of options with the help of architectural screening models. The research team first defined the key set of design solutions, in particular, the number of lander stages and the propellant type for each stage of the landing module and generalized the data in mathematical models.

According to researcher Kir Latyshev, a two-stage landing module is the most optimal version for expendable spacecraft even with the presence of a lunar orbiter as it has a smaller weight and lower fuel consumption as well as lower costs. A similar module was used under the Apollo program for astronauts’ delivery to the Moon in 1972: the lunar platform consisted of the landing and take-off stages to deliver two astronauts to the Moon and back to the spacecraft, leaving the landing stage on the Earth’s natural satellite.

"However, reusability changes all that. While one-and three-stage vehicles are still heavier than two-stage spacecraft, they allow repeatedly reusing more of the vehicle mass (approximately 70-100% compared to 60% for two-stage modules), thus saving funds for the production and delivery of new vehicles to the orbital station, which makes the lunar program cheaper as a whole," the press office quoted Latyshev as saying.