What killed early astronomy star?

PRAGUE - Astronomer Tycho Brahe uncovered some of the mysteries of the universe in the 16th century - and now modern-day scientists are delving into the mystery of his sudden death.

Yesterday, an international team of scientists opened his tomb in the Church of Our Lady Before Tyn near Prague's Old Town Square, where Brahe has been buried since 1601. After eight hours of work, they lifted from the tomb a tin box like a child's coffin in which Brahe's remains were placed after a previous exhumation, in 1901.

Brahe's extraordinarily accurate stellar and planetary observations, which helped lay the foundations of modern astronomy, are well-documented. But the circumstances surrounding his death at age 54 are murky.

It has been long thought that he died of a bladder infection. Legend said it was the result of his reluctance to breach court etiquette during a reception by leaving to use a toilet. Kidney disease was another suspect.

But tests conducted in 1996 on samples of his mustache and hair obtained in the 1901 exhumation showed unusually high levels of mercury. That led to a theory of mercury poisoning - even, possibly, murder.

One theory had it that his assistant, famed German astronomer Johannes Kepler, was among those to blame.

Born in 1546 at his family's ancestral castle, Brahe, a Dane, was in Prague in 1601 at the invitation of the Holy Roman Emperor Rudolph II, having had a disagreement with the Danish king.

Brahe's remains were in the yardlong box as expected.

Unexpectedly, however, the remains of Brahe's wife, supposedly buried by his side three years later, were not found.

Archaeologist Petr Veleminsky said the bodies of two other people were discovered in the crypt - one of a women no older than 20, the other of a child.

Jens Vellev, a Danish professor of medieval archaeology, who is leading an international team of scientists, said he decided nine years ago to seek permission to reopen the tomb because there had been no proper archaeological report on the 1901 exhumation. Vellev also hoped to gather better samples of mustache and hair - and, for the first time, samples of bone - so they could be analyzed using contemporary technology.

Scientists are interested in Brahe's skull as well. A part of the astronomer's nose was sliced off in a 1566 duel with a fellow nobleman as a student in the German city of Rostock, and the missing piece was replaced by a metal plate."It's been a fantastic day for us," Vellev said. "We've been waiting so long. All of us are happy."