The pioneering astronomer Johannes Kepler may have had his eyes on the heavens, but chemical analysis of his manuscripts suggests he was “willing to get his hands dirty” and may have dabbled in alchemy.

A team led by biotechnologist Gleb Zilberstein and chemist Pier Giorgio Righetti has found very significant amounts of metals associated with the practice including gold, silver, mercury and lead on the pages of Kepler’s manuscript about the moon, catalogued as “Hipparchus” after the classical astronomer.

Kepler, who died in 1630, drew on Copernicus’s work to find laws of planetary motion that paved the way for Isaac Newton’s theory of gravity. While he is known as a mathematician and astronomer, the historical record does not reveal whether he also studied alchemy – the ancient quest to transform base metals into gold or silver, cure disease and extend life.

But a paper published in the chemistry journal Talanta describes how researchers used acetate films to discover metals that suggest Kepler “might have started practising alchemy”.

The authors speculate that Kepler could have learned the “pseudo-chemical science” from his colleague Tycho Brahe, the great Danish astronomer, in Prague. Brahe had invited Kepler to join him at the court of Rudolf II in Castle Benatky near Prague in 1600. When Brahe died in 1601, Kepler succeeded him as mathematician to Rudolf II.

Alchemy, they point out, was still popular in the 16th and 17th centuries. Elizabeth I’s scientific adviser John Dee was an alchemist, and Brahe built an alchemical laboratory on the island of Hven, with 16 furnaces and equipment for the purification of metals. When Brahe’s body was exhumed in 2010, analysis of hair samples found they contained quantities of gold “up to 100 times higher than in a normal person today”.

“It is highly likely that Brahe transmitted his passion to Kepler, who might have started practicing the art of alchemy,” the paper continues, adding that it was likely “he was willing to get his hands dirty, as judged from the high levels of ‘classical metals’ used in this field on all pages of his manuscript Hipparchus” and that “he not only had his fingertips contaminated by these metals, but also the sleeves of his garments”.

Zilberstein – who has previously found traces of kidney disease on the manuscript of Mikhail Bulgakov’s The Master and Margarita, and analysed a letter of George Orwell’s to suggest that he may have caught the tuberculosis that killed him while in a Spanish hospital – told the Guardian that examining texts and manuscripts with analytical chemistry can reveal “information about what a person was eating, what this person was ill with, what medicines he used, what atmosphere he lived in”.

“It is very important to revisit the legacy of such people to find more about our history … These manuscripts are filled with amazing drawings and traces from the person who created them. If Kepler was an alchemist, then many processes that led to the formation of European culture, philosophy, science and industry can be understood.”

Unlike Brahe, there are no mortal remains of Kepler to test. The astronomer was buried in a local cemetery in Regensburg after dying suddenly of a fever aged 53. The cemetery was pillaged the following year during the thirty years’ war, and his grave swept away. Just his epitaph, which he composed for himself, remains: “I used to measure the heavens, / now I shall measure the shadows of the earth. / Although my soul was from heaven, / the shadow of my body lies here.”