The Ariane-5 rocket of Europe prepared for the 100th flight

The European rocket Ariane 5 is expected to make its 100th flight Tuesday.

It will orbit two large satellites from its operational base in Kourou, French Guiana.

Originally designed to launch a European space shuttle, the rocket has been adapted to form the heaviest telecommunications satellite, a market that has dominated for many years.

But the emergence of cheaper US rockets means that Ariane 5 will soon have to give way to a more competitive successor.

To be described as predictable, Ariane 6 – this vehicle is expected to debut in mid-2020.

A late order from Ariane 5 however ensures that the former workaholic will continue to fly for a while.

Two of its remaining missions include sending the BepiColombo survey from Europe to Mercury next month and setting up the $ 10 billion James Webb Space Telescope, following on from Hubble, in 2021.

"Ariane 5 was a great success and it's not over yet, we still have four or five years left with this product," said Alain Charmeau, who heads the rocket manufacturer ArianeGroup.

"And even with the 100th flight, we continue to improve the product, and we continue to gain a few extra pounds in terms of the payload we can offer our customers," he said. told BBC News.

Tuesday's telecom "passengers" tip the scales to more than 10 tons. Ariane will place them on a path that will take them to some 36,000 km above the Earth.

From this perspective, the Horizons 3e satellite will be able to provide connectivity services throughout the Asia-Pacific region, and the Azerspace-2 / Intelsat 38 platform will be able to do the same in Africa, Europe and Asia. Central.

The departure of Kourou is scheduled at 18:53 local time (21:53 GMT; 22:53 Paris time).

What is the record for Ariane-5?

Ariane 5 had a false career start after escaping 37 seconds after leaving the Kourou launch pad during its first flight in June 1996. This failure is due to an error in the Kourou launch software. control.

There was another absolute failure in 2003, but since then the reliability and accuracy of the rocket have been noticed.

For a long time, it would launch at least half of the major telecommunication satellites over the course of a year.

Among the more than 200 payloads launched over the last 22 years are the comet Rosetta mission, space telescopes, meteorological satellites, Galileo satellite navigation platforms, as well as the many telecommunications satellites.

Where does the competition come from?

California-based SpaceX has eroded Europe's dominant position, which can manufacture and sell its Falcon vehicles on the commercial market at a price that significantly hurts Ariane.

And SpaceX promises to further reduce costs because it regularly flies reusable rockets.

Jeff Bezos, the boss of online retail giant Amazon, is considering a similar approach with a new vehicle that he calls New Glenn.

At the same time, spaceships in general become smaller. Many are now the size of a shoebox.

A large number of start-ups are developing smaller rockets to try to adapt to this change of scale.

What future for Ariane?

Ariane's answer is the introduction of a simpler launcher to build and use, which maximizes the use of new generation manufacturing techniques, such as 3D printing .

This Ariane 6 rocket is on track for development, with all its engines being tested.

It will always be a single-flight disposable rocket; it will not be reusable. But the European Space Agency, which oversaw the design process, hopes the 40-50% reduction in unit cost will keep Ariane in a competitive position.

The rocket market is complex. It is distorted by geopolitical considerations. There are national security missions, for example, that will probably only be launched on a domestic rocket.

ArianeGroup is looking for stronger assurances from European governments that they will use Ariane 6 for all their institutional payloads.

This would help close the Ariane 6 case, said Mr. Charmeau.

"It's good to have a lot of people supporting Ariane 6, but there's a nuance between" support "and commitment, it's not the same thing.

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