We’re closing our space blog now after a disappointing morning at Cape Canaveral that saw Nasa scrub its first attempt to launch its Artemis 1 moon mission because of an engine issue.
But mission managers will point out this is a test flight designed to iron out mechanical issues and other problems to ensure astronaut safety ahead of placing human crews aboard in subsequent missions.
Thanks for joining us today, and I hope you’ll be with us when Nasa returns to try again, possibly as early as this Friday (2 September) depending on what engineers find as they troubleshoot the issue that caused today’s launch postponement.
If they don’t make it on Friday, the next available launch date after that is 5 September. Following that, they would have to wait until the middle of the month.
'Engine bleed' causes Artemis 1 launch scrub
Nasa says “an engine bleed that couldn’t be remedied” was the reason today’s scheduled launch of its Artemis 1 moon mission was scrubbed.
Engineers first became aware of the issue overnight as they loaded 2.76m litres of liquid hydrogen and liquid oxygen fuel into the tanks of the giant Space Launch System rocket.
All four R-25 engines from the rockets core stage needed to be “conditioned” with cryogenic propellant to bring them up to the correct temperature for launch, but one of the four failed to respond as Nasa expected.
The launch of #Artemis I is no longer happening today as teams work through an issue with an engine bleed. Teams will continue to gather data, and we will keep you posted on the timing of the next launch attempt. https://t.co/tQ0lp6Ruhv pic.twitter.com/u6Uiim2mom
— NASA (@NASA) August 29, 2022
The engine “didn’t get the high accuracy temperature that they were looking for,” launch control communicator Derrol Nail said, adding that the rocket would remain fuelled on launchpad 39B at Florida’s Kennedy Space Centre while engineers gathered data.
“The rocket is currently in a stable configuration,” he said. “The team was unable to get past the engine bleed that didn’t show the right temperature and ultimately the launch director has called a scrub for the day.”
Nail said the next available launch opportunity would be 12.48pm EDT (5.48pm BST) on Friday 2 September, but it was far from a certainty Nasa would take that opportunity.
“We must wait to see what shakes out from their test data they’re gathering now and the decision that’s to be made by the launch team about where to go from here,” he said.
Artemis 1 launch called off for today
Nasa has officially called off today’s planned launch of Artemis 1 because of a “conditioning” issue with one of the four engines on the rocket’s main stage.
The engine “didn’t get the high accuracy temperature that they were looking for,” launch control communicator Derrol Nail said of engineers’ efforts to “condition” the engine for launch.
The next attempt will likely be on 2 September.
More details to follow…
Artemis 1 timeline
While we await a decision on when, or if, today’s launch will take place, here’s a closer look at the mission timeline.
The Space Launch System carrying the Orion capsule is Nasa’s most powerful ever rocket with 15% more thrust in its core stage than the gigantic Saturn V rockets of the Apollo era half a century ago.
You can find these and other graphics in the official Artemis 1 press kit here.
After reaching lower Earth orbit about eight minutes into flight, a trans-lunar injection burn will increase Orion’s speed from 17,500mph to 22,600mph to escape the pull of Earth’s gravity and guide the craft to a precise point close enough to be captured by the moon’s gravity.
Here’s the official Nasa overview of the rest of the mission:
This Nasa tweet, with a clickable link, provides a closer look at the SLS rocket system and its component stages that will propel the Orion capsule to the moon.
🟢 Engines
— NASA_SLS (@NASA_SLS) August 23, 2022
🟢 Solid Rocket Boosters
🟢 Core Stage
🟢 Launch Vehicle Stage Adapter
🟢 Interim Cryogenic Propulsion Stage
🟢 Orion Stage Adapter
Get familiar with all the parts of the SLS rocket before launch by checking out our "Clickable Rocket" >> https://t.co/r8FgfdcDQm pic.twitter.com/iD5kohW8h5
Updated
Discussions over the engine issue are taking longer than first thought, and no decision has yet been reached whether to press ahead with today’s planned launch or scrub for the day.
According to Artemis 1 launch director Charlie Blackwell-Thompson, engineers are about to present her with some “modelling data”, following which a further discussion will be held and a decision made.
“We’ll have more information when we get it,” Nasa’s launch control commentator Derrol Nail says helpfully.
One of the most unpredictable elements of any rocket launch is weather, and scrubbed launches at Cape Canaveral, caused by lightning storms, low clouds, precipitation, strong winds or other violations of strict weather constraints, are not uncommon.
At a briefing on Sunday, the 45th Weather Squadron at the nearby Patrick Space Force base calculated the probability of launch weather being acceptable at 80% at the opening of the two-hour launch window at 8.33am (1.33pm BST), and the forecast worsening thereafter to 60% by its close.
240FPS video of the strike to the #SLS #Artemis Pad 39B #lightning towers. Looks like they did their job, they took at least three hits from my vantage point. #FLwx @natwxdesk pic.twitter.com/mYXQ5sIeKO
— Nick Stewart (@NStewCBS2) August 27, 2022
Thunderstorms are a regular summer occurrence in this part of Florida, and lightning struck the launchpad at Kennedy Space Centre several times on Saturday.
The SLS rocket is, however, protected by three adjacent giant lightning towers, which appear to have done their job. Jeff Spaulding, Nasa’s senior test flight director for Artemis 1, said the spacecraft was unaffected and “everything looks really good” for launch.
Engineers discuss 'troubleshooting plan'
Launch control says Nasa’s missions engineers are forming a “troubleshooting plan” to address a problem with one of the four R-25 engines on the SLS rocket’s core stage. The engine is not responding correctly to efforts to condition it with cryogenic propellant in order to raise its temperature for launch.
A decision could come in the next 10 minutes whether a fix can be found in time to still launch during today’s two-hour window, which closes at 10.33am local time (3.33pm BST) or if the launch must be delayed to another day.
The countdown clock is on a hold at T-40 minutes. The hydrogen team of the @NASA_SLS rocket is discussing plans with the #Artemis I launch director. Operational commentary continues at https://t.co/z1RgZwQkWS. pic.twitter.com/5J6rHVCe44
— NASA (@NASA) August 29, 2022
The countdown clock is currently in an unplanned hold at 40 minutes to lift-off. The next back-up day for launch will be 2 September if today’s attempt has to be scrubbed.
Updated
Nasa has released an official video giving an overview of the Artemis project, and today’s scheduled flight in particular.
A number of different voices, including astronauts, senior Nasa officials and others, explain why we’re going back to the moon, and what it takes for us to get there.
The launch of #Artemis I is right around the corner.
— NASA Artemis (@NASAArtemis) July 26, 2022
Explore the reference guide and press kit for the mission to get all the details: https://t.co/K9HMk78udo pic.twitter.com/ov3KoC4eZR
Bill Nelson, the Nasa administrator and himself a former space shuttle astronaut, also laid out the rationale in an interview with NBC’s Meet the Press on Sunday. He said the ultimate goal is placing humans on Mars, and that returning to the moon, and building a base there, is a crucial stepping stone for that journey:
We need to be on the moon for much longer periods of time than just landing like we used to, stayed a couple of days and left. This time we’re going back, we’re going to live there, we’re going to learn there. We’re going to develop new technologies, all of this so we can go to Mars with humans.
All of this is to develop where we may be living on other worlds. They may be floating worlds, they may be the surface of Mars. But this is just part of our push outward, our quest to explore, to find out what’s out there in this universe.
With the countdown clock on hold at 40 minutes to launch, Nasa has cleared one of the issues it was working, a suspected crack on a fuel tank flange.
“There was a line of ice that formed on an inner tank on the core stage where there is a flange,” said Nasa communicator Derrol Nail, the voice of launch control.
“Engineers have taken a long look and come up with a conclusion … ice formed along the line is essentially air that’s been chilled by the tank that gets trapped inside a crack in the foam, but not inside the actual tank.
“It looks like something is leaking when in fact it’s not,” he said.
Updated
Nasa rocket Artemis 1 to blast off to the moon
Good morning and welcome from me, Richard Luscombe, on Florida’s space coast. In short order this morning – weather gods and mechanical issues permitting – Nasa will launch a historic mission setting humanity back on course for the moon.
So what exactly are we watching here? Artemis 1 is the first test flight of Orion, the US space agency’s brand new six-person capsule, coupled to the mighty Space Launch System (SLS), which will become the most powerful rocket ever to leave Earth.
No humans are aboard today’s mission, for which a two-hour launch window opens at 8.33am local time (1.33pm BST). But if the 42-day flight, to 40,000 miles beyond the moon and back, is successful, Nasa will have taken a significant milestone towards its stated goal of returning humans to the lunar surface by 2025.
Only 12 people, all men, have ever walked on the moon, most recently in 1972 on the Apollo 17 mission. Nasa seeks to close that 50-year gap with the Artemis programme (in Greek mythology, Artemis is the twin sister of Apollo) and says it will land the first woman there on Artemis III, currently scheduled for three years’ time.
The major objective is ensuring that Orion is capable of sustaining human life through lengthy, deep-space explorations and withstanding 2,800C (5,000F) temperatures of re-entry to bring astronauts safely back to Earth. But a host of other boxes also need checking.
Mission managers at Kennedy Space Centre have been loading the rocket overnight with 2.76m litres (730,000 gallons) of liquid oxygen and liquid hydrogen fuel that will power its ascent from Earth, and launch director Charlie Blackwell-Thompson will make the final go, no-go decision 15 minutes before the scheduled launch time.
Liquid hydrogen replenish is closed and now in revert to troubleshoot the bleed on engine number 3. Teams are working to increase pressure in the bleed on engine 3 to continue conditioning the four RS-25 engines on @NASA_SLS for launch. https://t.co/wEUPRpb8q2
— NASA (@NASA) August 29, 2022
Engineers are currently working several issues that could yet postpone things … one of the four R-25 engines on the rockets core stage is not responding as expected to efforts condition it with cryogenic propellants that would bring it up to correct temperature for launch, and a suspected crack has been discovered in the thermal protection system in the rocket’s main stage.
Both are potential show-stoppers.
We’ll bring you all the developments as they happen. Meanwhile, as the countdown continues, take a read of our preview of the mission and its objectives here:
