Rare earths for spatial measurements

Researchers from CEA-INAC developed a small cryorefrigerator, replacing liquid helium by a more efficient rare-earths based material.
Measuring instruments embarked on board satellites are usually cooled with liquid helium to ensure accurate operation. The problem is that this consumable runs out as fast as its ability to store energy at low temperatures, which shortens the operation duration of spatial cooling systems.

So researchers from ECA-INAC developed a small cryorefrigerator, replacing liquid helium by a more efficient rare-earths based material. As a result: the tank reaches a minimal temperature of 3.8 K (a world record) for a cooling power of 15 mW at 4.5 K, starting from a pre-cooling temperature of 20 K.

This technological breakthrough could help equip the future missions of the European Space Agency (ESA) as early as 2028 with the Athena Project, whose aim is the observation of distant cosmic X-rays.

Les Défis du CEA, Oct. 2014