But now, Intuitive Machines, a company based in Houston, is planning to launch its spacecraft to the moon early on Wednesday, setting up a possible landing later this month. If successful, it will be the first landing for the United States since the last of the Apollo missions in 1972 and the first commercial spacecraft ever to touch down on the lunar surface. The company’s phone-booth-size lander, Odysseus, is aiming for near the moon’s south pole, a region that is of particular interest to NASA because of the existence of water in the form of ice in its permanently shadowed craters.
Although the spacecraft is owned and operated by Intuitive Machines, NASA has several science experiments on board and is paying the company $118 million to deliver them to the surface. The flight is part of a $2.6 billion space agency program designed to send a fleet of robotic spacecraft, operated not by NASA but private industry, to the moon over the next several years to bolster the space agency’s attempt to land astronauts there.
The effort demonstrates the growing role the commercial space industry has assumed in space exploration. NASA now relies on contractors not just to fly cargo and astronauts to the International Space Station, but also to develop the spacecraft that will land astronauts on the moon and the spacesuits they will wear while there. It is also looking to the corporate sector to build the habitats that could eventually replace the space station in Earth orbit.
A successful lunar landing by a commercial vehicle would mark a significant milestone in the exploration of space by private enterprise, which NASA hopes will eventually help open up new economic and scientific activity on and around the moon. “By advancing our capabilities to operate on the lunar surface, the mission sets the stage for more ambitious endeavors, including the establishment of lunar bases and the exploration of potential resources,” Intuitive Machines said in a statement.
All of that remains years away, and landing on the moon is extremely difficult. In the first of the uncrewed flights to the lunar surface, a spacecraft developed by Astrobotic, a company based in Pittsburgh, suffered a problem with its propulsion system last month and sprang a leak, preventing it from reaching the lunar surface. Shortly afterward, a spacecraft operated by the Japanese space agency landed softly, making Japan the fifth country to land on the moon’s surface. But the spacecraft ended up on its side.
NASA’s moon program has had some recent setbacks, as well. The space agency had been hoping that a quartet of astronauts would fly around the moon in its Orion spacecraft later this year, a mission, known as Artemis II, that would be somewhat similar to the Apollo 8 flight in 1968. But last month, NASA Administrator Bill Nelson said the flight will be delayed to September 2025 because the space agency needs to further study Orion’s heat shield, which showed more charring than anticipated.
Artemis III, the flight that will transport astronauts to the surface, was also pushed back from 2025 to no earlier than September 2026. This time, the issue is delays in SpaceX’s development of its Starship spacecraft, which is supposed to ferry the crew to and from the lunar surface. Nelson said there are also delays with developing the spacesuits the astronauts will wear on the moon. That effort is being led by Axiom Space, another private space company.
“I want to emphasize that safety is our number one priority,” Jim Free, NASA’s associate administrator, said during a briefing last month. “As we prepare to send our friends and colleagues on this mission, we’re committed to launching as safely as possible. And we will launch when we’re ready.”
Intuitive Machines says that after an extensive test campaign it is ready to launch as early as 12:57 a.m. Eastern time Wednesday, setting up a landing about nine days later.
“The vehicle is ready,” Stephen Altemus, CEO of Intuitive Machines, said in an interview in October. “It’s performing wonderfully. … We know the odds of what we’re up against. We’ve done extensive testing beyond development testing, to make sure that the vehicle is performing as designed. And we’re confident coming out of our reviews that we’ve hammered all those issues flat and that we know how the vehicle behaves.”
Odysseus will be carried to space on a SpaceX Falcon 9 rocket from Cape Canaveral, Fla., and will then speed toward the moon while undergoing complicated steps along the way. Once the spacecraft separates from the rocket, it will use special cameras to take images of stars that will allow it to autonomously orient itself in the correct position so that its solar arrays point toward the sun. Once powered up, it will turn on its communication radios to make contact with controllers on the ground.
On the way to the moon, the spacecraft will use its propulsion system to make course corrections to keep it on the right path, “like a car driver making minor adjustments with the steering wheel along a straight stretch of road,” the company said. It will aim for a spot near the moon that will allow it to enter lunar orbit, similar to how basketball players aim for the square on the backboard of the hoop. “If a basketball player hits the backboard square with a shot, the ball is likelier to go in the hoop,” it said.
As it approaches the moon, the spacecraft will fire its engine again, this time to put it into an orbit about 62 miles above the lunar surface. The plan calls for it to orbit the moon approximately 12 times while waiting for the lighting conditions to be right on the lunar surface. Each pass also will present a challenge for the spacecraft, as it alternates between the heat of the sun and the cold of darkness that will require “heat drawn from batteries to keep systems warm.” The spacecraft will lose communications with the ground for about 45 minutes on each orbit when the moon blocks Odysseus’s radio signal.
As the vehicle begins its descent toward the surface, it will fire its engine to drop from 62 miles to just over six miles. Then its cameras and lasers will feed data to the onboard navigation computers that will autonomously guide it to a safe place on the surface. At about 100 feet, it will flip itself to a vertical position with its landing legs pointed down. During the descent, the engine thrust will continuously decrease as the lander burns fuel and, as a result, gets lighter and lighter.
Because lunar dust will kick up as the vehicle approaches the surface, it won’t use cameras or sensors for the final touchdown, relying instead on what the company calls “inertial measurement,” which the company said senses acceleration and rotation like a human’s inner ear. “Terminal descent is like walking toward a door and closing your eyes the last three feet,” the company said. “You know you’re close enough, but your inner ear must lead you through the door.”
The landing speed will be about three feet per second, or about 2 mph.
Odysseus is carrying several scientific payloads from NASA, including an instrument that will capture images of the dust plume kicked up by the spacecraft’s engines. Since it anticipates eventually landing multiple spacecraft close to one another, NASA wants to better understand what effects landings have on the moon’s surface and environment.
It is also carrying a camera system designed by Embry-Riddle Aeronautical University students and faculty that will be ejected from the spacecraft at about 100 feet above the moon’s surface to take images of the vehicle during the landing sequence.
Source : https://www.washingtonpost.com/technology/2024/02/13/intuitive-machines-lunar-lander-launch/