Humans Returning to the Moon

As published on 17 December, 2018, hopefully in 2028, NASA will bring back the humans to the surface of the moon competing for attention alongside a presidential election and the return of the Summer Olympics to Los Angeles. As per NASA plan, a cluster of modules will be separated by a lunar lander in an elliptical orbit around the moon which is called Gateway. In one stage the lander will be taken to a low lunar orbit and then been separated post which the descent module is to take care of the rest of the journey to the lunar surface.

A crew of four would need few days or may be two week on the surface before boarding the ascent module, which is a way back to the Gateway. After one year of President Donald Trump formally directing NASA to return humans to the moon in Space Policy Directive (SPD) 1, the agency had outlined the plan to execute this plan along with emphasizing the language in the policy to do so in a sustainable manner with the international and commercial partners. However, the agency says that it is still struggling to get approval on the two of the biggest elements of the plan, i.e., the Gateway and a ‘human-class’ lunar lander. The Deep Space Gateway, as per the plan, must test technologies needed for future human deep space missions, including expeditions for Mars proposed for the 2030s. Once SPD-1 was effective, the Deep Space Gateway was renamed to Lunar Orbiting Platform-Gateway. The ideas were many but NASA did not have many means of getting to the surface of the moon. However it is known that the agency had started to study concepts for lunar lander designs and tried hard to solicit proposals from industry to study the various possible ways to get astronauts from the Gateway to the surface. However NASA finds a three-stage approach best for the lunar lander where there will be a transfer vehicle in addition to the ascent and descent modules. Jason Crusan, director of NASA’s Advanced Exploration Systems division said “By going to this three-stage architecture, it opens up a lot more of that trade space” which meant having more flexibility in how each stage will be able to reach the moon which currently is too small enough to fit in. When they reach there, however, the three stages would be integrated at the Gateway, with the astronauts boarding the lander. The transfer vehicle is expected to take the lander from the Gateway’s near-rectilinear halo orbit, an elliptical orbit, i.e., about 1,000 and 70,000 kilometres above the moon, to a circular low orbit which is 100 kilometres high. The ascent and descent stages are expected to then go down to the lunar surface, and then finally the ascent stage would fire its engines to go straight to the Gateway. This approach is expected to allow the ascent stage and the transfer vehicle to be reusable, which is beneficial for the overall architecture. The council meeting members had advised potential additional studies for the Gateway concept along with the National Academies or the National Space Council’s UAG.

By: Anuja Arora

Content: https://spacenews.com/is-the-gateway-the-right-way-to-the-moon/