Tag Archives: lunar

CAN YOU PROVIDE MORE DETAILS ABOUT THE ARTEMIS PROGRAM AND SPACEX’S INVOLVEMENT IN RETURNING ASTRONAUTS TO THE LUNAR SURFACE

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The Artemis program is NASA’s ongoing effort to return astronauts to the Moon by 2024 and establish a long-term human presence there. Its goals include landing the first woman and next man on the lunar south pole region by 2024. Furthermore, NASA aims to build a sustainable lunar architecture and infrastructure necessary to support lunar exploration missions once every year thereafter. An additional goal is to use the Moon as a testing ground and proving ground to advance technologies and resources needed for future missions to Mars.

SpaceX is playing a critical role in supporting NASA’s deep space exploration plans under Artemis. In 2021, NASA selected SpaceX to develop the first commercial human lander to return astronauts to the lunar surface as part of the Artemis program. Known as Starship, SpaceX’s fully reusable super heavy-lift launch vehicle is intended to be the primary transportation method to reliably and affordably send significant amounts of cargo and people to the Moon and Mars.

Under the $2.89 billion contract awarded by NASA, SpaceX will use Starship to land astronauts on the Moon’s surface for the first time since the Apollo 17 mission in 1972. NASA’s goal is for Starship to annually transport six astronauts from lunar orbit to multiple locations on the lunar south pole region where astronauts will conduct extended surface missions for up to a couple weeks.

Specifically, SpaceX is responsible for developing the Starship human landing system variant capable of the high-energy transfer orbit needed to travel from Earth to lunar orbit. This includes the flight-proven Starship spacecraft and Super Heavy rocket that will propel it. Starship is a fully integrated, orbital-class launch vehicle that can transport over 100 metric tonnes to low Earth orbit, according to SpaceX’s specifications. For crewed Artemis missions, an enhanced version of Starship designed for human safety and robustness will be used.

Starship’s capabilities are well-suited to minimize the complexities and risks associated with lunar surface missions. It will provide an unprecedented combination of mass and volume to send significant amounts of cargo, habitats, rovers, and other payloads to the Moon needed to establish sustainable long-term exploration. Being fully reusable allows Starship to drastically reduce the costs of lunar exploration compared to traditional expendable approaches.

After launching on the Super Heavy booster, Starship will remain in lunar orbit using onboard propulsion while crews onboard Orion, NASA’s crew capsule, approach and dock. Orion and its service module provide safe passage for astronauts traveling from Earth to lunar orbit. Once the Orion crew capsule docks, up to four Artemis astronauts wearing xEMU space suits will transfer across and board the waiting Starship for their journey to the lunar surface.

Upon arrival on the Moon, Starship’s spacious descent stage serves as a landing platform and habitat capable of supporting crews for up to 6.5 days. It has more than twice the interior space as the Apollo command module and service module combined. Not only will it land the astronauts, but Starship can also transport scientific instruments, experiments, rovers, habitats, supplies and more to sustain lengthy surface expeditions. Its departure stage later returns to lunar orbit to rendezvous and dock with Orion.

SpaceX will perform a series of uncrewed demonstration missions to refine and prove out Starship’s capabilities before crewed Artemis missions occur. This includes proving out aspects like high-precision landing technology through multiple in-space demonstrations and on the lunar surface. The first lunar flights will focus on delivering substantial amounts of cargo before humans. This delivery of cargo will support later surface activities by Artemis astronauts and enable other agencies and commercial partners through NASA’s Artemis Accords.

SpaceX’s Starship human landing system represents a paradigm shift that will enable NASA to achieve its objectives under the Artemis program in a safe, innovative and cost-effective manner. With reusable Starship providing the main transportation method, ambitious exploration of the lunar surface will be made practical in ways not possible with traditional architectures. If successful, Starship will cement SpaceX as a leader in advanced heavy-lift launch and human space transportation while also establishing the technologies needed to eventually send the first astronauts to Mars.

WHAT ARE SOME OF THE KEY ADVANTAGES OF THE NEAR RECTILINEAR HALO ORBIT NRHO FOR LUNAR MISSIONS

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The near rectilinear halo orbit, or NRHO, is a special type of halo orbit that was selected by NASA for the Gateway – a small space station that will orbit the Moon and serve as a staging point for Artemis missions. There are several advantages of using an NRHO for the Gateway and future lunar missions compared to other possible orbits.

One major benefit of the NRHO is its stability. Halo orbits around the second Lagrangian point (L2) of the Earth-Moon system are dynamically stable, meaning a spacecraft can remain in this orbit without having to perform complex orbital maintenance maneuvers to counteract perturbations. This allows for long-term dwell of orbital assets like the Gateway. In contrast, low lunar orbits require station-keeping to account for orbital decay over time. The intrinsic stability of the NRHO reduces operational costs and Complexity for missions utilizing the Gateway.

A linked advantage is that the Gateway’s NRHO enables continuous line-of-sight communication with Earth without interruptions from the Moon getting in the way. This “stable remote platform” feature provides mission planners assured and uninterrupted command and control of robonaut or manned sorties from the Gateway to the lunar surface, increasing safety. Low lunar orbits by comparison have intermittent communications blackout periods. Reliable comms through Gateway are crucial for surface missions.

Another key benefit of the Gateway’s NRHO is its free return capability. If engines fail on a spacecraft departing the Gateway for the lunar surface, the craft’s trajectory will return it to the Earth-Moon system without the need for correction. This ensuresBuilt insafe mode return for astronautswithout depleting mission resources. Low lunar orbits lack this fail-safe free return capacity, necessitating precise maneuvers and significant propellant usage for any emergencies.

The phasing properties of the NRHO mean that missions departing from the Gateway can access any part of the lunar surface within a single orbit, offering coverage flexibility for surface sorties, landings or cargo deliveries. This facilitates global access unlike low polar or equatorial orbits which see the same side of the Moon on each pass. The Gateway’s NRHO phasing point allows surface missions to utilize minimal propellant for optimal transit to target locations.

The orbital altitude of the NRHO above the lunar surface, averaging around 70,000 km, also provides an ideal vantage point for long-term scientific observation of the Moon without interference from short-term fluctuations. Platforms in the Gateway will be able to conduct persistent solar astronomy studies as well as high-resolution imaging surveys of the entire lunar farside which remains occluded from Earth-based observation. Long duration monitoring supports rigorous analysis impossible through brief fly-bys alone.

The NRHO actually fosters economical trajectories allowing spacecraft to take advantage of gravity assists from both Earth and Moon, reducing propellant demands. Missions can utilize minimum energy ballistic transfers from low Earth orbit to the Gateway then onward surface excursions. This conserves precious onboard fuel compared to direct transfers and lower orbits. Lower propellant needs cuts spacecraft mass and launch vehicle lift requirements, easing deployment logistics and decreasing costs. Recent studies have shown NRHO transit mass savings can reach 30% compared to lunar surface injection.

The Gateway’s Near Rectilinear Halo Orbit provides unmatched accessibility, communications, crew safety assurances, scientific value, and most importantly – cost effectiveness – through its inherent dynamical characteristics. Its advantages over direct low lunar orbits truly establish it as the optimal orbital choice for establishing a sustainable lunar presence and enabling the long term exploration, development and commercialization of the Moon under the Artemis program and beyond. The decision to position the Gateway in NRHO demonstrates the care and thoroughness that has gone into mission architecture design for enabling sustainable and ambitious human exploration of the lunar surface from this unique vantage point.