Today’s Artemis launch attempt has been cancelled.
A potential problem with one of the engines and a potential crack in the thermal protection system on one of the flanges halted the Artemis countdown clock at T-40 minutes while engineers assessed an issue conditioning engine 3, one of four RS-25 engines on the bottom of the Space Launch System rocket’s core stage.
Launch controllers condition the engines by increasing pressure on the core stage tanks to bleed some of the cryogenic propellant to the engines to get them to the proper temperature range to start them. Engine 3 is not properly being conditioned through the bleed process.
Teams also were also assessing what appears to be a crack in the thermal protection system material on one of the flanges on the core stage. The flanges are connection joints that function like a seam on a shirt, are affixed at the top and bottom of the intertank so the two tanks can be attached to it.
The Space Launch System rocket and Orion spacecraft are in a stable condition.
The Artemis I, the first integrated test of NASA’s deep space exploration systems, is an uncrewed flight test that will provide a foundation for human deep space exploration and demonstrate our commitment and capability to return humans to the Moon and extend beyond.
The first in a series of increasingly complex missions, Artemis I is The Orion spacecraft and Space Launch System (SLS) rocket was to lift off from Launch Pad 39B at NASA’s Kennedy Space Centre in Florida today, between 08h33 EDT (14h33 local time) and 10h33 EDT (16h33 local time).
When it is rescheduled, the mission, to perform a distant retrograde orbit around the Moon, will take 42 days, 3 hours, 20 minutes to travel about 2,1-million kilometres. Splashdown, in the Pacific Ocean, will be on 10 October 2022.
During this flight, Orion will launch atop the most powerful rocket in the world and fly farther than any spacecraft built for humans has ever flown. Over the course of the mission, it will travel 450 000 kilometres from Earth and 64 000 kilometres beyond the far side of the Moon.
Orion will stay in space longer than any human spacecraft has without docking to a space station and return home faster and hotter than ever before.
This first Artemis mission will demonstrate the performance of both Orion and the SLS rocket and test our capabilities to orbit the Moon and return to Earth. The flight will pave the way for future missions to the lunar vicinity, including landing the first woman and first person of color on the surface of the Moon.
With Artemis I, NASA sets the stage for human exploration into deep space, where astronauts will build and begin testing the systems near the Moon needed for lunar surface missions and exploration to other destinations farther from Earth, including Mars. With Artemis, NASA will collaborate with industry and international partners to establish long-term exploration for the first time.
Blast-off
SLS and Orion will blast off from Launch Pad 39B at NASA’s modernised spaceport at Kennedy. Propelled by a pair of five-segment boosters and four RS-25 engines, the rocket will reach the period of greatest atmospheric force within 90 seconds.
The solid rocket boosters will burn through their propellant and separate after approximately two minutes, and the core stage and RS-25s will deplete propellant after approximately eight minutes.
After jettisoning the boosters, service module panels, and launch abort system, the core stage engines will shut down and the core stage will separate from the spacecraft, leaving Orion attached to the interim cryogenic propulsion stage (ICPS) that will propel it toward the Moon.
As the spacecraft makes an orbit of Earth and deploys its solar arrays, the ICPS will give Orion the big push it needs to leave Earth’s orbit and travel toward the Moon. This maneouvre, known as the trans-lunar injection, precisely targets a point about the Moon that will guide Orion close enough to be captured by the Moon’s gravity.
In space
Orion will separate from the ICPS approximately two hours after launch. The ICPS will then deploy ten small satellites, known as CubeSats, along the way to study the Moon or head father out to deep space destinations.
As Orion continues on its path from Earth orbit to the Moon, it will be propelled by a service module provided by ESA (European Space Agency) that will course-correct as needed along the way. The service module supplies the spacecraft’s main propulsion system and power.
The outbound trip to the Moon will take several days, during which time engineers will evaluate the spacecraft’s systems. Orion will fly about 97 kilometres above the surface of the Moon at its closest approach, and then use the Moon’s gravitational force to propel Orion into a distant retrograde orbit, traveling about 64 000 kilometres past the Moon. This distance is 48 000 kilometeres farther than the previous record set during Apollo 13 and the farthest in space any spacecraft built for humans has flown.
For its return trip to Earth, Orion will get another gravity assist from the Moon as it does a second close flyby, firing engines at precisely the right time to harness the Moon’s gravity and accelerate back toward Earth, setting itself on a trajectory to re-enter our planet’s atmosphere.
Landing
The mission will end with a test of Orion’s capability to return safely to Earth. Orion will enter Earth’s atmosphere traveling at about 40 000 kph. Earth’s atmosphere will slow the spacecraft down to a speed of about 480 kph, producing temperatures of approximately 2 800 degrees Celsius and testing the heat shield’s performance.
Once the spacecraft has passed this extreme heating phase of flight, the forward bay cover that protects its parachutes will be jettisoned. Orion’s two drogue parachutes deploy first, at 7 600 metres, and within a minute slow Orion to about 160 kph before being released.
They are followed by three pilot parachutes that pull out the three main parachutes which will slow Orion’s descent to less than 32 kph. The spacecraft will make a precise landing within eyesight of the recovery ship off the coast of San Diego.
Recovery operations
The Landing and Recovery Team, led by NASA’s Exploration Ground Systems program at Kennedy, will be responsible for safely recovering the capsule after splashdown. The interagency landing and recovery team consists of personnel and assets from the US Department of Defense, including Navy amphibious specialists and Air Force weather specialists, and engineers and technicians from Kennedy, Johnson Space Center in Houston, and Lockheed Martin Space Operations.
Before splashdown, the team will head out to sea in a Navy ship. At the direction of the NASA Recovery Director, Navy divers and other team members in several inflatable boats will be cleared to approach Orion. Divers will then attach a cable to the spacecraft and pull it by winch into a specially designed cradle inside the ship’s well deck. The vessel will transport the spacecraft and other hardware to a pier at US Naval Base San Diego for transport to Kennedy.
Open water personnel will also work to recover Orion’s forward bay cover and three main parachutes. If teams are able to recover the jettisoned cover and parachutes, engineers will inspect the hardware and gather additional performance data.