Lightning showers moved within five nautical miles of Launch Pad 39B just after midnight, forcing Launch Director Charlie Blackwell-Thompson to delay the start of propellant loading by 55 minutes. But the six-hour process finally began at 1:13 am. EDT. The only other topic under discussion as the countdown entered its final hours was troubleshooting to find the cause of a momentary communication error in one of the channels that transmit commands and telemetry to and from the Orion spacecraft. It was not immediately clear what impact, if any, the power delay and troubleshooting might have on the scheduled 8:33 a.m. launch time. But engineers were optimistic about landing NASA’s most powerful on its long-awaited maiden flight sometime during a two-hour launch window. The carefully designed fueling process is required to load 196,000 gallons of liquid oxygen and 537,000 gallons of hydrogen into the rocket’s massive core stage. The upper stage requires another 22,000 gallons of oxygen and hydrogen, for a total of 750,000 gallons of propellant. The Space Launch System’s moon rocket atop pad 39B early Monday awaits blastoff on a mission to send an uncrewed Orion capsule on a 42-day shakedown flight past the moon and back. NASA The SLS’s four shuttle-era engines and two extended-belt solid-fuel boosters will generate 8.8 million pounds of thrust to propel the 5.7 million-pound rocket away from pad 39B at the Kennedy Space Center. The rocket part of the Artemis 1 mission will last just one hour and 36 minutes, augmenting the Orion capsule and the European Space Agency’s service in space, beyond Earth orbit and into lunar orbit. After a close flyby at an altitude of just 60 miles, Orion will return to a distant orbit around the moon for two weeks of testing and checkout. If all goes well, the capsule will drop back toward the moon for another close flyby on Oct. 3 that will set up a high-speed descent into the Pacific Ocean on Oct. 10. The 322-foot-tall SLS rocket, the most powerful ever built by NASA, during launch at pad 39B. NASA NASA plans to follow the Artemis 1 mission by launching four astronauts on a lunar orbit in 2024, setting the stage for the first astronaut landing in nearly 50 years, when the first woman and next man will step on the surface. Time frame 2025-26. But first, NASA must prove that the rocket and capsule will perform as planned, and that starts with the launch of Artemis 1 on Monday. Starting about 6.6 seconds before liftoff, the four RS-25 engines at the base of the main stage will ignite and throttle to full thrust, creating a combined thrust of two million pounds. When the countdown reaches zero, after a round of lightning checks on the computer to verify engine performance, commands will be sent to ignite both solid rocket boosters. At the same time, the signals will detonate four explosive screws at the base of each booster, releasing the SLS from the launch pad. Solid rocket boosters provide the lion’s share of the power needed to lift the SLS out of the dense lower atmosphere, firing for two minutes and 10 seconds before falling away at an altitude of 27 miles. The RS-25 center stage engines will continue the ascent on their own, firing for another six minutes to propel the rocket to an altitude of 87 miles. The main stage’s RS-25 engines will fire for eight minutes, boosting the ship to an altitude of 87 miles before shutting down. The flight plan called for the rocket’s upper stage, which will carry the unmanned Orion capsule and the European Space Agency-provided service module, to separate from the now-empty core stage and continue to coast skyward to an altitude about 1,100 miles, the high point, or apogee, of its original orbit. The engine powering the Intermediate Cryogenic Propulsion Stage, or ICPS, was expected to fire 51 minutes after liftoff to increase the low point, or perigee, of the orbit from 20 miles to about 115. Reaching that low point forty-five minutes later — one hour and 36 minutes after launch — the ICPS was programmed to fire the RL10B’s engine for 18 minutes, increasing the vehicle’s speed to about 22,600 mph, more than 10 times faster quickly from a rifle bullet. This is what is required to break free from Earth’s gravity, lifting the apogee to a point in space where the moon will be in five days. The Orion capsule’s planned orbit will take it 40,000 miles from the far side of the moon — the furthest from Earth of any human-rated spacecraft. NASA After deploying its four solar wings and separating from ICPS, the Orion capsule will head for a 60-mile flyby of the moon on Sept. 3 and then into a “far retrograde orbit” taking the spacecraft farther from Earth — 280,000 miles — than any previous human-rated spacecraft. The flight is the first in a series of missions intended to establish a permanent presence on and around the moon with a lunar space station called Gateway and periodic landings near the south pole, where ice deposits can be accessed in cold, permanent shadowed craters. Future astronauts may be able to “mine” this ice, if it is present and accessible, turning it into air, water, and even rocket fuel to greatly reduce the cost of space exploration. More generally, Artemis astronauts will conduct extensive exploration and research to learn more about the origin and evolution of the Moon and to test the hardware and processes they will need before sending astronauts to Mars. The goal of the Artemis 1 mission is to pass the Orion spacecraft, testing its solar power, propulsion, navigation and life support systems before returning to Earth on October 10 and a 25,000 mph plunge into the atmosphere that will undergo protective thermal shield at a hellish 5,000 points. Testing the heat shield and confirming that it can protect astronauts returning from deep space is the No. 1 priority of the Artemis 1 mission, a goal that requires the SLS rocket to first send the capsule to the moon. If all goes well with the Artemis 1 mission, NASA plans to launch a second SLS rocket in late 2024 to boost four astronauts into free-return orbit around the moon before sending the first woman and next man to land on its surface moon near the south pole on the Artemis 3 mission. That flight, targeted for launch in 2025-2026, depends on the readiness of new spacesuits for NASA’s spacewalkers and a lander built by SpaceX based on the design of the company’s reusable Starship rocket. An artist’s impression of the Orion spacecraft passing by the moon. NASA SpaceX is working on the lander under a $2.9 billion contract with NASA, but the company has provided few details or updates, and it’s not yet known when NASA and the California rocket maker will actually be ready for the Artemis landing mission. 3. But if the Artemis 1 test flight is successful, NASA may review its requirement for a super-heavy lift rocket to get the initial missions off the ground. With 8.8 million pounds of launch thrust — 15 percent more than Saturn 5 — the SLS rocket is the most powerful ever built by NASA. Congress ordered NASA to build the rocket after the space shuttle was retired in 2011, requiring the agency to use leftover shuttle components and existing technology where possible in an effort to keep costs down. But management mistakes and technical problems led to billions in delays and cost overruns. According to NASA’s Inspector General, the US space agency is “projected to spend $93 billion on Artemis (the Moon program) through FY 2025.” “We also project the current cost of manufacturing and operating an SLS/Orion system at $4.1 billion per launch for Artemis 1 through 4, although the Agency’s ongoing initiatives to increase affordability seek to reduce this cost.” . Among the causes cited as contributing to SLS’s astronomical price tag: the use of sole-source, cost-plus contracts, and the fact that except for the Orion capsule, its subsystems, and supporting launch facilities, all components are expendable and “single “.use” as opposed to emerging commercial spaceflight systems. In stark contrast to SpaceX’s commitment to fully reusable rockets, everything but the Orion crew capsule is discarded after a single use. As SpaceX founder Musk likes to point out, this is like flying a 747 jumbo jet from New York to Los Angeles and then flying the plane. “This is troubling,” said Paul Martin, NASA’s inspector general, in an interview with CBS News. “This is a single-use expendable system as opposed to some of the launch systems that are on the commercial side of the house, where there are multiple uses. This is a single-use system. And so our $4.1 billion per flight . . . it’s troubling enough that we said in our reports that we see it as unsustainable.”
