NASA resumes countdown to launch mission to the Moon this Wednesday (16)

NASA has resumed the countdown to launching its first return mission to the Moon. The American space agency intends to launch Artemis 1 at dawn on Wednesday (16), starting at 3:04 am (GMT), when a two-hour window opens for the start of the flight.

It will be the first mission of the SLS (acronym for Space Launch System), a super-rocket developed for the manned return to the Moon. This time, however, as it is a test, the Orion capsule will fly without anyone on board.

If all goes well, the plan is to launch the manned Artemis 2 in 2023 (most likely to 2024), in the first human trip around the Moon since Apollo 17, held in December 1972. Artemis 3, officially still slated for 2025 (but almost certainly destined to delay), would perform the first manned lunar landing of the 21st century.

For now, James Free, associate administrator for development of NASA’s exploration systems, doesn’t even like to talk about these future missions, because everything depends on a success with Artemis 1. goes well, we will see the farthest flight from Earth ever carried out by a capsule intended to transport humans.

complicated path

Much can be said about the development of the program, except that it was little troubled. It’s a story that has been going back and forth since the crash of the space shuttle Columbia in 2003, which made the agency rethink the future of its exploration missions.

The rocket alone, the SLS, cost US$ 23.8 billion (originally estimated at US$ 10 billion) and was supposed to have its first flight in 2016. Now the fight is not to let it escape until 2023.

Orion, in turn, represents an important partnership between Americans and Europeans: the crew module was made in the USA, but the service module, which includes the propulsion system, is provided by the European company Airbus. Its development has cost, since 2006, US$ 20.4 billion. Thus, the total cost amounts to almost US$ 50 billion.

To complicate matters, the SLS is a strange mix of new rocket and old technologies. Designed this way by order of the US Congress, it incorporates technologies originally created in the 1970s for the space shuttle. The rocket’s first stage engines, by the way, are the same. Literally. They unscrewed it from the old NASA vehicles and plugged it into the new rocket.

The logic was to preserve jobs from the old program and reduce development costs. The first part worked, but the second clearly didn’t. And now the agency has a return-to-the-moon system that is perhaps too expensive to be sustainable.

It is estimated that each launch will cost US$ 4 billion and that the agency is unable to have a cadence of flights greater than one every two years.

NASA swears that the cost will come down and that it can operate the system more efficiently. Recent events do not seem to support this idea.

facing hurricanes

The original plan for this year was to launch the Artemis 1 mission in the first quarter of 2022. It slipped into the first half. And so the first launch attempt didn’t come until August 29th.

Problems with a temperature sensor on one of the first stage’s engines led to the countdown being interrupted, with 40 minutes left for takeoff.

A new attempt was made on September 3, but excessive leaks of liquid hydrogen during the rocket’s fueling, above tolerated limits, once again stopped the countdown from advancing three hours before the launch window opened.

Instead of returning the vehicle to the assembly building, NASA opted for an effort to carry out repairs on platform 39B itself at the Kennedy Space Center in Florida. A rocket fueling exercise conducted after repairs was successful. But then what stopped another flight attempt was Hurricane Ian, which forced the agency to take the rocket back to the assembly building on September 26.

The recall procedure triggered a new series of staging resumes, pushing a new launch effort to mid-November. The rocket arrived back at platform 39B on the 4th, aiming for a launch this Monday (14).

And then another hurricane, Nicole, crossed Florida. The agency pushed the launch date to this Wednesday (16), but did not have time to collect the vehicle, which was exposed to the hurricane’s wind. At dawn last Thursday (10), winds of up to 160 km/h hit the rocket.

It tells NASA that everything happened within the limits supported by the vehicle. There is some controversy over this, given the height of the rocket (98 meters). Fact is, there was some damage.

Some of the filling material between the emergency escape system and the Orion capsule on top of the rocket came off.

Even as it proceeded with the countdown, NASA was analyzing the risk that more of this material would deteriorate into debris that could hit the SLS body during flight.

There were also problems with one of the second stage telemetry connectors. The agency continued to try to restore its operation, but noting that, even if it was not possible, there was redundancy.

Moral of the story: nothing was considered an impediment to the release. The count started at 3:54 am on Monday, and the agency expects to carry it out, with takeoff at 3:04 am on Wednesday. After two hurricanes, at least the weather now brings good news: the probability of good weather for launch is 90%. With a two-hour window, just one technical problem to stop the flight once again.

The total duration of the mission, which involves taking the capsule into a distant retrograde orbit around the Moon, where it will stay for about a week before returning to Earth, depends on the day of departure. If it leaves this Wednesday, the forecast is for the return to take place on December 11, making a spaceflight of 26 days. Less than the 42 possible if the mission had taken place in August, but still longer than any of the Apollo missions in the past century.