Tycho and Kepler (51 page)

A month
later Kepler’s youngest child, Anna Maria, was born. Now he had two grown children by Barbara and four younger ones by Susanna, although two of those would not live to adulthood. There had been five others who had died in infancy or early childhood. There had been Friedrich, the shining boy who had died in Prague, and Kepler’s beloved stepdaughter Regina, who had died as a young married woman.

In the days just after Anna Maria’s birth, when Kepler could not leave his wife’s side long enough to oversee the printing of his next series of ephemerides, he told his printer to work instead on a book that he had begun as an essay when he was a student in Tübingen. During the Prague years he had expanded the essay into a short story, much to the delight of his friends, for he laced it with
puns and allusions that they could appreciate. This was, in fact, the piece that he had feared might jeopardize his mother’s case in the witch trial, and with the trial long past he felt vindicated in publishing it, with some notes pointing out how it might have been used out of context.
Somnium
⁴
(The Dream) consists of a twenty-eight-page story and fifty pages of notes and diagrams and is widely
regarded as the first work of science fiction. The hero and narrator, in the course of his travels, visits Uraniborg, where he finds Tycho and many assistants all speaking languages he does not understand until he learns sufficient Danish. Most of the story takes place on the Moon and is about the way the heavens and Earth appear to inhabitants there.

The notes concerned much more than the
possible misuse of the story in the witch trial. It was here that Kepler showed that he understood the concept of gravity better than he is often given credit for. He described clearly the point between Earth and Moon where their separate gravitational attractions exactly cancel out.

The printing of
Somnium
proceeded sporadically between printing
runs
for the ephemerides. It was not finished
when Kepler set out from Sagan in October to try, once again, to recover some of his back salary. This time it seemed there was hope. After being put off again and again, Kepler had been promised that if he appeared in Linz on November 11, he would be paid some interest on investments there. He also planned to attend a meeting taking place near that time in Regensburg at which the future of his
patron Wallenstein, now fallen from grace, hung in the balance.

Kepler was exhausted when he rode out of Sagan on October 8. He had pushed the printer and himself unmercifully. He had needed to ship ahead of him, for the autumn book fair in Leipzig, a large stock of books: fifty-seven copies of ephemerides, sixteen copies of the
Tables
, and seventy-three other books. It had also taken time
and effort to gather together all the documentation he had collected through the years about everything that was owed him.

After Leipzig, Kepler rode to Regensburg and arrived there on November 2 after a cold autumn journey on a nearly worthless old horse that he sold in the city for a few florins. He felt ill but, determined not to neglect anything he had set out to do, shrugged off his illness
as no more than a nuisance. For a man his age, it was more than that. He grew worse, his fever soared, and he lapsed into delirium
⁵
. A doctor came and bled him, which did not help.

At last a Protestant pastor was summoned. Kepler drifted in and out of consciousness for several days and in his few lucid moments tried to explain to the pastor that he had done his utmost to reconcile Catholics
and Protestants. The pastor admonished the dying Kepler that this was like expecting to bring together Satan and Christ. Kepler, as usual, was not dissuaded from his own beliefs. When asked on what basis he hoped for salvation, he answered, “Solely on the merit
⁶
of our Savior Jesus Christ, in whom is found all refuge, solace, and salvation.” Those words were the very essence of Protestantism,
and no pastor could take exception to them.

On November 15, 1630, Kepler died. Though his grave has been
lost
, he was not buried in obscurity. Some of the most powerful and illustrious men of the empire were in Regensburg for the meeting Kepler had planned to attend, and many of them walked in the funeral procession for the imperial mathematician they had so celebrated but also so poorly supported.
That evening there was a meteor shower. As it was reported at the time, fiery balls fell from heaven.

Kepler’s gravestone in the Protestant cemetery bore an epitaph that he had written himself:

I measured
⁷
the heavens, Now the earth’s shadows I measure, Skybound, my mind. Earthbound, my body rests.

Tycho Brahe in the portrait from his book
Astronomiae Instauratae Mechanica
, 1598, printed shortly before he went to Prague.

Johannes Kepler in a portrait painted in 1610 when he was at the height of his career as Imperial Mathematician in Prague.

Knutstorps Borg, Tycho Brahe’s birthplace and ancestral manor house, as it appears today.

Knutstorps Borg, in a seventeenth-century drawing by Gerhard von Burman.

King Frederick II of Denmark, Tycho’s patron, who granted him the fiefdom of Hven and whose support enabled him to build Uraniborg, in a portrait by an unknown artist.

Tycho’s elevation drawing for Uraniborg.

Tycho’s plan of the gardens of Uraniborg, with the mansion at the center.

The great globe, begun in Augsburg in 1570 and completed at Uraniborg a decade later. It became the centerpiece of Uraniborg’s library.

The great mural quadrant, one of Tycho’s most splendid instruments, built into the structure of Uraniborg in 1582. Tycho considered this portrait of himself an excellent likeness. The two men shown in the foreground were not part of the mural; they were part of this particular drawing of the mural.