The ALMA space telescope in the Chilean Andes suffered a cyberattack over the weekend that has downed its website and suspended its work, the observatory announced Wednesday.

ALMA, the world's most powerful telescope for observing molecular gas and dust, studies the building blocks of stars, planetary systems, galaxies and life itself, according to the European Southern Observatory (ESO), its co-operator.

The attack Saturday on ALMA's computer systems did not compromise its powerful antennas or any scientific data, it said on Twitter.

The cyberattack forced the suspension of astronomical observations, left the observatory with limited email services, and its website still offline four days later.

"The threat has been contained and our specialists are working hard to restore affected systems," said the ALMA tweet.

"Given the nature of the episode, it is not yet possible to estimate a date for a return to regular activities," it added.