GEO control room

Achieving difficult things


Meet Gareth Williams, one of many behind the Meteosat Third Generation mission

GEO control room
GEO control room

As we gear up for the end-of-the-year launch of the first of the Meteosat Third Generation satellites, we’re shining a spotlight on the important people who are making this mission happen.

Last Updated

05 December 2022

Published on

05 December 2022

Gareth Williams credits his career in the space sector to a telegramme.

The year was 1990. Williams had just graduated with a Master’s degree in Astronautics and Space Engineering from Cranfield, a university just north of London and was living in Edinburgh. Looking for work opportunities at the European Space Research and Technology Centre (ESTEC) in the Netherlands, he wrote to ESTEC hoping to obtain a list of companies they used as contractors. For good measure, he included his CV.

“Instead of a letter in response, I received a telegramme. It was really bizarre to have someone from the Post Office knock on my door early on a Saturday morning and say, ‘Here, you’ve got a message,’” said Williams.

The message was a fortuitous one: Would he be interested in coming for an interview for the ESA Young Graduate Trainee programme? If so, he should call this phone number immediately. When he did, he was told there would be a ticket waiting for him at Edinburgh airport the next morning for a flight to the Netherlands.

Gareth Williams
Gareth Williams, Head of the Flight Operations Division

“It happened to be that ESTEC didn’t have enough candidates for their trainee programme. Not only was I invited for interview, I ended up being selected for one of the positions and worked at ESTEC for a year and a half. I’ve worked for different companies and space agencies ever since,” he said.

Now, Williams is putting his more than 30 years’ experience to good use preparing for the December launch of the first Meteosat Third Generation satellite, MTG-I1. As Head of the Flight Operations Division, he is responsible for ensuring the satellite, once safely in orbit, gathers the scientific data uniquely available from satellites for subsequent use by weather forecasters and climate agencies in order to improve short- and long-range weather forecasts.

To do this, he oversees several teams that are experts in a variety of areas: operating the satellite and its payload instruments, writing and testing detailed and complex procedures, ensuring the satellite stays in its optimal position by executing manoeuvres, managing the complex systems to maintain contact between the satellite and the ground. In addition, he oversees the controllers who maintain watch over the satellites and ground systems 24 hours a day, every day of the year.

“The key thing with MTG is that this a completely different design of spacecraft from its predecessors, so we have to learn how to continue our successful run operating previous generations of Meteosat with this revolutionary new satellite,” Williams said.

“It’s a bit like getting a new car. The first generation of Meteosat satellites were like an early-model Volkswagen Golf – basic but they did the job. When we transitioned to the Meteosat Second Generation (MSG) series, it was like upgrading to a Volkswagen Passat: bigger and more capable than its predecessors, and with more gizmos and gadgets, although, fundamentally, both still work the same way.

“MTG, though, is like upgrading to a Tesla. It works in a completely different way from what came before and brings greatly expanded capabilities, as well as a few new constraints. Our job is to be ready for this new kind of satellite.” 

Part of this preparation has required engineers to understand how to maintain the satellite in its proper orbit as it travels through the Earth’s uneven gravitational field. MTG controls its position and orientation using thrusters, unlike MSG, which was stabilised using the gyroscope effect, by spinning at 100 revolutions per minute. Although the absence of spin makes controlling the satellite’s temperature – essential for the satellite’s sensitive electronics – more complicated, it provides greater freedom in designing the payload instruments. MTG is also more autonomous than MSG, with an improved ability to perform its mission without intervention from controllers, and to detect and react to anomalies.

On the day of the launch, Williams anticipates feeling mixed emotions.

“I’ll feel relief that it is safely in orbit, together with the realisation that the next few months are going to be a lot of hard work across EUMETSAT. But the whole point of being here is to achieve difficult things,” he said.

“People here at EUMETSAT genuinely care about what we do because we recognise its importance. Doing our job properly results in more accurate weather forecasts that benefit peoples’ lives in many ways: knowing when to pack a raincoat, predicting winter snows so roads can be salted, helping farmers plan their harvest, aiding civil infrastructure planning, and even saving lives by the early detection of severe storms.

“We also play an important role in the global fight against climate change by gathering information about the environment – anything from temperature data from Antarctic ice floes to the path of an ocean mammal as it moves around the world.

“If we don’t change things, and we don’t realise how much things are already changing, our grandchildren and great-grandchildren are going to have a very different life to the one we’d wish for them to have.”


Sarah Puschmann