A rare 17th-century brass astrolabe, often described by historians as a “medieval supercomputer,” is set to go under the hammer at Sotheby’s in London, with an estimated value of nearly £94 million.

From Royal Collections to Global Spotlight

The intricately crafted astronomical instrument was once part of the royal collection of Jaipur’s Maharaja Sawai Man Singh II and later passed on to Maharani Gayatri Devi, one of India’s most iconic royal figures. It has since remained in private ownership until its upcoming auction.

Experts note that historical records link its craftsmanship to Lahore-era artisans, adding a South Asian dimension to its provenance.

Ancient Science Meets Modern Recognition

Astrolabes—flat, layered metal instruments—were used for centuries to:

• Track time and celestial movements
• Map stars and planetary positions
• Determine direction toward Makkah
• Calculate distances, heights, and even astrological predictions

Dr Federica Gigante of the Oxford Centre for the History of Science described such instruments as “three-dimensional worlds compressed into two-dimensional form,” comparing them to early multi-functional computing devices.

A Technological Marvel of Its Time

According to historians, astrolabes were first developed in ancient Greece in the 2nd century BCE and later refined across the Islamic world from the 8th century onward, with major production centres in Iraq, Iran, North Africa, and Andalusia (modern Spain).

By the medieval period, they had become essential scientific tools for astronomers, navigators, and scholars across civilisations.

Craftsmanship Under Spotlight

Sotheby’s Islamic and Indian Art specialist Benedict Carter described the piece as “possibly the largest and most important astrolabe of its kind ever offered at auction.”

Close examination of its engraved rings and inscriptions highlights extraordinary craftsmanship, reflecting the advanced scientific knowledge of its era.

A Bridge Between Eras

The upcoming auction underscores how ancient scientific instruments are increasingly being re-evaluated not just as artefacts, but as early expressions of computational thinking and applied astronomy.

If the estimate holds, the piece could become one of the most expensive scientific artefacts ever sold.