Ellen Phiddian
Cosmos science journalist
Despite living just before the invention of the telescope, the Danish astronomer Tycho Brahe made huge contributions to European astronomy.
He was also, like many scientists of his era, a very keen and secretive alchemist. His castle, called Uraniborg, was fitted with observatories in its towers and an alchemy laboratory in the basement. The building was demolished shortly after his death in 1601.
But a few clues about Brahe’s activities remain.
Danish scientists found traces of the materials Brahe worked with on glass and ceramic shards on the now-Swedish island of Ven, where Uraniborg once stood.
The shards were uncovered in a 1988–90 excavation, and it’s believed they belonged to the castle’s laboratory.
The researchers have published their findings in Heritage Science.
They used a technique called laser ablation inductively coupled mass spectrometry to analyse the shards. This process involves blasting a sample with lasers, generating particles that are sent through a device called a mass spectrometer which identifies compounds from their mass.
Study co-author Professor Kaare Lund Rasmussen, a researcher at the University of Southern Denmark, says this technique generated “very effective and stunning results.”
“Most intriguing are the elements found in higher concentrations than expected – indicating enrichment and providing insight into the substances used in Tycho Brahe’s alchemical laboratory,” says Rasmussen.
Rasmussen and colleagues have previously published several studies on the bones of Brahe, including data on what he and his wife ate, and evidence that he probably wasn’t murdered by mercury poisoning, despite conspiracy theories springing up almost immediately after his death.
In the new study, the researchers found enriched traces of the elements nickel, copper, zinc, tin, antimony, tungsten, gold, mercury, and lead on 4 of the shards. One glass shard didn’t have any alchemical traces.
Some of these elements, like gold and mercury, are mainstays of an alchemist’s laboratory. The researchers compared their findings with the scant writings about Brahe’s alchemical work. They suggest that some of these elements (copper, antimony, gold and mercury) could be connected to a medicine Brahe made called elixir Tychonis.
“It may seem strange that Tycho Brahe was involved in both astronomy and alchemy, but when one understands his worldview, it makes sense,” says study co-author Poul Grinder-Hansen, curator at the National Museum of Denmark.
“He believed that there were obvious connections between the heavenly bodies, earthly substances and the body’s organs. Thus, the Sun, gold and the heart were connected. The same applied to the Moon, silver and the brain; Jupiter, tin and the liver; Venus, copper and the kidneys; Saturn, lead and the spleen; Mars, iron and the gallbladder; and Mercury, mercury and the lungs.”
Brahe was known to be interested in the medical applications of alchemy, writing that most alchemists who pursued the making of gold ended up wasting time, labour and money.
Other elements present on the pottery are more puzzling.
“Tungsten is very mysterious. Tungsten had not even been described at that time, so what should we infer from its presence on a shard from Tycho Brahe’s alchemy workshop?” says Rasmussen.
It’s possible it made its way in there without Brahe noticing it. But Rasmussen says there is also a chance that Brahe had heard of the work done by German scientist Georgius Agricola, who had identified tungsten as “wolfram” in tin ores during the early 16th Century.
“But this is not something we know or can say based on the analyses I have done. It is merely a possible theoretical explanation for why we find tungsten in the samples,” says Rasmussen.
Rasmussen is keen to see if he can glean more about Brahe’s activities through looking at other artefacts in the lab.
“Next I would like to analyse a new and larger set of shards, maybe 20 or 25, in order to catch more elements which might be present,” he tells Cosmos.
