Europe tests a new engine design aimed at nothing

The European Space Agency:
home of dead-end projects
The European Space Agency (ESA) today announced that it has successfully completed a static fire test program of a new rocket engine, dubbed Greta, that uses alternative fuels in order to save the environment.
Greta uses hydrogen peroxide and ethanol as propellants, a more sustainable alternative with a lower carbon footprint compared to monomethyl hydrazine propellant used by most traditional rocket engines in this thrust range.
Greta was ignited multiple times from July to November 2025 and showed stable operations, including controlled shutdowns. During the test campaign the engine fired continuously for over 40 seconds at a time. Greta was tested on a new, low-cost and versatile mobile test stand with instruments measuring data such as pressure and temperature, which will be used to further optimise the engine.
The problem is that this engine is not being built for any specific rocket or spacecraft. As the press release notes vaguely, “This type of engine could be used on lunar landers or on kick stages, such as Astris that is being developed for Europe’s Ariane 6 rocket.”
In other words, this is a test program only, and could very well end up on the scrap heap once completed, because it belongs to no private company aimed at making profits.
NASA did these kinds of projects for decades, all for naught. The agency would make a splash with its press release, the propaganda press would extol blindly the wonders that have been achieved, and then the project would complete and get quietly shelved, stored somewhere in the government archives (possibly in the same place they put Indiana Jones’ Ark of the Covenant).
ArianeGroup is building this engine for ESA, so there is a small chance the company might decide to use it in a future rocket or spacecraft, but only if it makes sense financially. And there is no indication that this engine’s development is tied to financial concerns, in the slightest. For example, the program only calls for another round of static fire engine tests — using “parts for the flight-like motor design” — in 2027, more than a year hence. At that pace the engine will be obsolete before tests are completed.

The European Space Agency:
home of dead-end projects
The European Space Agency (ESA) today announced that it has successfully completed a static fire test program of a new rocket engine, dubbed Greta, that uses alternative fuels in order to save the environment.
Greta uses hydrogen peroxide and ethanol as propellants, a more sustainable alternative with a lower carbon footprint compared to monomethyl hydrazine propellant used by most traditional rocket engines in this thrust range.
Greta was ignited multiple times from July to November 2025 and showed stable operations, including controlled shutdowns. During the test campaign the engine fired continuously for over 40 seconds at a time. Greta was tested on a new, low-cost and versatile mobile test stand with instruments measuring data such as pressure and temperature, which will be used to further optimise the engine.
The problem is that this engine is not being built for any specific rocket or spacecraft. As the press release notes vaguely, “This type of engine could be used on lunar landers or on kick stages, such as Astris that is being developed for Europe’s Ariane 6 rocket.”
In other words, this is a test program only, and could very well end up on the scrap heap once completed, because it belongs to no private company aimed at making profits.
NASA did these kinds of projects for decades, all for naught. The agency would make a splash with its press release, the propaganda press would extol blindly the wonders that have been achieved, and then the project would complete and get quietly shelved, stored somewhere in the government archives (possibly in the same place they put Indiana Jones’ Ark of the Covenant).
ArianeGroup is building this engine for ESA, so there is a small chance the company might decide to use it in a future rocket or spacecraft, but only if it makes sense financially. And there is no indication that this engine’s development is tied to financial concerns, in the slightest. For example, the program only calls for another round of static fire engine tests — using “parts for the flight-like motor design” — in 2027, more than a year hence. At that pace the engine will be obsolete before tests are completed.













