PRAGUE, Czech Republic » Some contend it was a crime of passion committed by a jealous king. Others insist it was murder inspired by professional rivalry between two celebrated astronomers. Or maybe it was a death by natural causes — a burst bladder, perhaps?

Seeking to solve a 400-year-old mystery, a team of Czech and Danish scientists last week exhumed the body of the 16th-century Danish astronomer Tycho Brahe, whose celestial observations laid the groundwork for modern astronomy and who died in Prague in 1601, age 54.

Revered in both the Czech Republic and in his native Denmark, Brahe catalogued more than 1,000 new stars and his astronomical observations helped clear the way for later breakthroughs by his assistant, the German astronomer Johannes Kepler.

But it is the questions surrounding Brahe’s death that have stumped historians for centuries.

Leading the quest for the truth is Jens Vellev, a self-styled Danish Indiana Jones and archaeologist at Aarhus University in Denmark whose team will analyze hair samples from Brahe’s once long and droopy mustache and will also take a CT scan of his bones, nose and teeth.

Brahe, who sported a distinctive gold and silver prosthetic nose — having lost the bridge of his real nose in a duel — was long thought to have died after his bladder burst. Legend has it that 11 days before his death he attended the banquet of a nobleman and was too polite to leave the table to go to the toilet.

Medical experts have scoffed at that theory, noting that bladder ruptures are highly unusual and that Brahe probably died from kidney failure. But even today, when Czechs excuse themselves from the table to go to the bathroom, they have been known to say, "Pardon me, I don’t want to end up like Tycho Brahe."

Suspicion of treachery has also fallen on Kepler, whom some have accused of murdering his mentor in order to pilfer his astronomic ideas. Kepler later used Brahe’s measurements to come up with the laws of planetary motion.

Others contend that Brahe was killed by his cousin, Eric Brahe, on the orders of the Danish king, Christian IV, enraged over rumors that Tycho Brahe, a father of eight, was having an affair with the king’s mother. Eric Brahe is alleged to have slipped some mercury into Tycho’s glass, causing him to die in delirious pain.

Vellev said it took him nearly 10 years to convince the local authorities and the priest at Prague’s Our Lady Before Tyn Church to allow him to exhume Brahe’s body, which was returned to the church’s crypt on Friday after a rousing funeral Mass.

He said he appealed to their sense of history and justice, even as he insisted that he did not buy the murder theories surrounding Brahe’s death.

In his view, he said, it was more than likely that Brahe, an alchemist, may have taken a fatal overdose of mercury while self-medicating for a painful kidney ailment. Alternatively, he may have accidentally ingested mercury during the course of one of his experiments.

A cantankerous and sometimes misanthropic genius, Brahe was born Tyge Ottesen Brahe in 1546 in Scania, at the time part of Denmark. He studied astronomy at the University of Copenhagen and in Germany and worked at the court of Holy Roman Emperor Rudolph II when Prague was an imperial city.

In 1572, he detected a new star in the constellation Cassiopeia, a startling discovery at a time when the heavens were thought to be unchanging.

Vellev sought to play down the chances that a murder would be solved. Exhuming Brahe’s remains, he said, was as invaluable for what it would show about his life as his death. For example, scientists will study his teeth to determine his diet. DNA testing could also help determine whether rumors of a royal affair are well-founded and whether he could be the father of a Danish king.

The results of the exhumation will be revealed by next spring.

"We may never get an answer and solve the mystery for certain," Vellev said. "But I am more interested in learning more about the life of Tycho Brahe than about his death."

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