All hail the Ariane 5 rocket, which doubled the Webb telescope’s lifetime

The Ariane 5 rocket has the James Webb Space Telescope on it.

There were two great pieces of news about the telescope this weekend. It was reported that after a two week deployment process, the telescope completed its work. The next steps in science operations are not new.

The other piece of news, which was less well-covered but still important, emerged during a news conference on Saturday. Mike Menzel, NASA's Mission Systems Engineer, said that the agency had finished its analysis of how much fuel remained on the telescope. Menzel said that there is enough propellant on board for 20 years of life.

The performance of the European Ariane 5 rocket that launched Webb on a precise trajectory on Christmas Day is the reason why this is twice the conservative pre-launch estimate.

The telescope was fueled with a mixture of hydrazine fuel and dinitrogen tetroxide oxidizer. The fuel was needed for the journey to a stable point in space, about 1.5 million km from Earth, where the scientist will conduct science observations. The remainder will be used to maintain the space station's position around the stable Lagrange point.

Every kilogram of fuel saved on the journey to the Lagrange point could be used to extend its life. NASA had already contemplated a costly and risky robotic refueling mission because ten years seemed like a fairly short operational period for such an expensive and capable space telescope. Now that should not be necessary, as Webb has at least two decades of life left.

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The performance of the Ariane 5 rocket is a big part of this. Europe would use its reliable Ariane 5 rocket to lift the telescope into space in exchange for time for European scientists to use the telescope.

Ariane 5 program manager Rudiger Albat talked about how European rocket scientists approached the launch. Engineers and technicians involved in the production of the rocket know which components are going on which Ariane 5 vehicle. An engineer might say, "I'll take a second look at the piece to make sure it's the best it can be."

The Ariane 5 program selected the best components for the project. The main engine used in the program was especially precise during testing. Albat said that it was one of the best Vulcain engines they had ever built. It has a precise performance. It would have been a crime to not do it.

The Ariane 5 was launched two weeks ago and the attitude was the same as for other components.

Albat admitted that the days leading up to the launch were nerve-racking. Albat said that the European space community could take pride in the fact that the space shuttle was able to unfurl its wings. He said that he feels totally relaxed. A lot of scientists who have been watching the development of Webb for two decades can say the same thing.