The goal of Project Artemis, named after the sister of Apollo and daughter of Zeus in ancient Greek mythology, is to create a long-term human presence on our closest celestial neighbor
Launch window - the period of time in which a rocket must be launched in order for it to reach its destination and after the hydrogen leak from engine #3 on August 29, 2022 was not used, now it is about another launch attempt on Saturday, September 3 for the first flight to the moon since 1972 of a spacecraft intended to carry humans there. If all goes well, Project Artemis will move forward on schedule to land people on the moon in 2025.
The goal of Project Artemis, named after the sister of Apollo and daughter of Zeus in ancient Greek mythology, is to establish a long-term human presence on our closest celestial neighbor, and eventually explore further afield. It includes NASA's very heavy rocket, the Space Launch System (SLS), which has never been launched before, and the Orion Multi-Purpose Crew Vehicle (MPCV), which has been in space only once.
Unlike the command and service chambers of the Apollo missions that were powered by hydrogen fuel cells, Orion is a solar-powered spacecraft. Its unique X-wing solar arrays can be moved forward or backward to reduce pressure on the probe during high-thrust maneuvers. It can carry six astronauts for 21 days in space. The unmanned Artemis 1 mission, however, could last up to 42 days.
Artemis also differs from Apollo in being an international project. Orion includes a cabin for the astronauts that is made in the USA and a service cabin that is made in Europe and contains a supply of fuel, water, air, solar arrays and accelerators.
The dependence on the sun for energy imposes some limitations on the launch date of Artemis 1 because the geometry of the Earth and the moon must be such that the Orion spacecraft will not be in the shadow of the sun for more than 90 minutes at any point during the flight. The earliest launch window will open at 08.33:29 EST on August 2, and additional windows will be on September 5 and XNUMX.
The SLS rocket will place Orion in orbit around the Earth, then its core stage will be ejected and fall into the ocean. Most of the energy needed to fly a spacecraft to the moon is used in this first stage of the flight, just to reach a low Earth orbit. Orion will then be pushed out of Earth orbit and into lunar orbit by the rocket's second stage, called the Intermediate Cryogenic Propulsion Stage (ICPS).
Orion will then separate from ICPS and in the following days will glide to the Moon. Launch is usually one of the most dangerous parts of any spaceflight, especially a new rocket. If Artemis 1 successfully reaches orbit around the country, it will be a significant milestone in the project.
During the mission, Orion will also deploy ten mini-satellites called cubesats. One of these, BioSentinel, will contain yeast to observe how the environment of weightlessness and radiation affects the growth of micro-organisms. Another cubesat, NEA Scout, will deploy a solar sail and then fly to a nearby asteroid for a closer look. At the same time, IceCube will circle the moon and look for ice deposits on or near the surface of the moon that could be used by future astronauts.
Entry into lunar orbit will occur at an altitude of 100 km above the surface of the moon. Orion will fire its thrusters to slow the spacecraft and allow the moon's gravity to trap it into orbit. The spacecraft will circle the moon in an unusual and far-off spiral orbit - in the opposite direction to the moon's spin. A particular orbit It was originally selected for a test flight on Orion as part of a now-cancelled mission To learn to deflect asteroids from their course.
During this phase, Orion will travel up to 70,000 km from the Moon and reach the furthest distance from Earth ever for a spacecraft capable of carrying astronauts. If astronauts were on board, they would get a great view of the distant Earth and the Moon.
Orion will spend six to 23 days in lunar orbit, after which it will fire its thrusters again to accelerate out of lunar orbit and put itself back in orbit toward Earth.
The surface of the moon can reach 120 degrees Celsius during the day and drop to -170 degrees Celsius at night. Such large temperature changes can cause significant thermal expansion and contraction, so it was necessary to build the Orion spacecraft from materials capable of withstanding significant thermal stress without failing. One of the goals of the mission is to test this, and more importantly, to make sure that the breathable atmosphere inside the capsule is maintained throughout.
Around the Moon, the astronauts will also be outside the Earth's magnetic field, which normally shields us from cosmic radiation. Radiation in space The deep is a serious concern in any future human mission to the Moon. The longest Apollo mission (Apollo 17) lasted 12 and a half days - Orion will stay in deep space three to four times longer. The engineers, therefore, will also closely monitor the radiation environment inside the capsule (editor's note: for this purpose there will be Israeli experiment-GrManny examines the radiation that will be absorbed by two dolls, one of which will "wear" a protective vest from the Israeli company Stammard).
Upon its return to Earth, the Orion crew capsule will separate from the service module, which will be discarded, and then enter the atmosphere with the help of its heat shield. The capsule will descend and deploy parachutes to land in the sea. In fact, this is the most crucial part of the mission: ensuring that the capsule can survive the high entry velocities of a spacecraft returning from the moon and then make a safe landing. To do this, the heat shield must withstand temperatures of 2,750 degrees Celsius when Orion decelerates from 40 km/h - this is significantly hotter than the temperatures encountered when the spacecraft return from low Earth orbit.
Artemis-2, which is scheduled to be launched in 2024, will carry four astronauts and circle the moon at an altitude of about 9,000 km above its surface. The astronauts on Artemis-2 will become the record holders for the greatest distance from Earth that humans have ever reached.
NASA also just announced about A short list of 13 landing sites near the moon's south pole for the first lunar landing mission, Artemis-3, which aims to land humans there in 2025. Whether they reach that goal will ultimately depend on how things go for the previous two phases.
For an article in The Conversation
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