Meteosat-7: The ‘Grandaddy’ Of Weather Satellites

Daily space

Some of the spacecraft at the National Space Centre are easier to spot than others. The Soyuz spacecraft, smack in the middle of our main entrance, is unmissable. But you may not have spotted our shiny Meteosat spacecraft, suspended above the Orbiting Earth gallery. Meteosat is one of the most precious artefacts in our collection, but it can be easily overlooked.

It lacks the glamour of a rocket or spaceship, but chances are that Meteosat has had more of a direct impact on your daily life than any other artefact in the Space Centre.

That’s because Meteosat is a weather satellite. If you checked the weather forecast this morning before planning your day, you relied on the images and climate data that the Meteosat satellites capture every 15 minutes, 24 hours a day. They beam back pictures of clouds, fog and upcoming storms, they monitor events like volcano eruptions (remember the airline havoc caused by the Icelandic volcano back in 2010?), and they track global changes in ocean temperatures to measure climate change.

We take them for granted, but it’s these cameras in space that give us the confidence to plan for the weekend weather and more importantly, warn us when major storms or other natural events are on their way.

How Meteosat works

Our Meteosat is the real deal. Back in 1997, it was the back-up, or flight spare, for Meteosat-7 in case the original satellite malfunctioned or even blew up on launch. Once Meteosat-7 was safely in orbit, its twin became available for display and it arrived at the National Space Centre. But only after we promised never to launch it ourselves! Our Meteosat has the right hardware and cameras to actually work in space. We’d just need a bit of fuel and a rocket!

But in all seriousness, it’s wonderful to be able to get up close and personal with a real-life satellite and imagine the stunning view its twin must have from space.

The real Meteosat-7 hangs out at 36,000 kilometres above the Earth, along with many other weather and TV satellites. It speeds along at a whopping 11,000 kilometres per hour, allowing it to orbit in sync with the turning Earth. This means that it always sees the same part of Earth and the antennas back on Earth always know where to find the satellite. But to see weather patterns across the whole planet, we need multiple Meteosat satellites spread out around the Earth. Currently there are three Meteosat satellites (8, 9, 10) monitoring the weather above Europe, Africa, and the Indian Ocean.

Each Meteosat satellite is a drum-shaped cylinder covered in shiny blue solar panels to power its electronics inside. It has an oval hole in its side where the optical and infrared camera points through, and a small rocket engine underneath to move the satellite in case of debris. A large antenna at the top sends all the images and data back to weather stations in Europe.

The Meteosat satellites each spin like a top at a rapid 100 revolutions per minute for extra stability. Just like a spinning top, a spinning satellite can naturally keep its orientation constant. Stop spinning and, like a top, it wobbles.

Well-deserved retirement

Today Meteosat-7 is known as the ‘grandaddy’ of weather satellites. Meteosat-7 launched in September 1997 and was only expected to last five years. Instead it exceeded all expectations and operated for a full twenty years, orbiting above the Indian Ocean.

A few months ago, in April 2017, Meteosat-7 was officially retired and moved to a ‘graveyard orbit’ above the working satellites, so that it wouldn’t create a collision risk in the future. Meteosat-8 has replaced Meteosat-7 and there are already plans for a next generation of Meteosat satellites to carry on the vital work.

So the next time you’re checking the weather forecast, spare a thought for the hard-working spacecraft like Meteosat-7 flying thousands of kilometres above our heads. They make quite the impact on our daily lives.