HISTORY OF ASTRONOMY IN

PRAGUE

KEVIN SMITH OCTOBER 2012

THE ASTRONOMICAL CLOCK

Image taken 17th October 2012 at 12.57 local time

Present day time is shown as 12 noon (golden hand)This must be UT since the clock directly above showed 1pm

Sun is shown in Libra, about to pass into ScorpioNo moon indicated – in reality moon waxing at about 5%Sidereal time indicates just before 2, calculated Local Sidereal Time is 13:44

THE ASTRONOMICAL CLOCK 2

Moving statues were added in the 17th century. They represent vanity, greed, death frivolous entertainment.

THE ASTRONOMICAL CLOCK 3

The Apostles were added after repair in 1865-1866, these appear as the hour is struck

THE CLOCK AND CLOCK TOWER

The calendar below was added in 1870.

The clock has been repaired many times throughout it’s history.In May 1945 it was fired upon by German artillery during the Prague uprising.

Restored to working order in 1948 after ‘considerable effort’.

TOURISTS PHOTOGRAPHING TOURISTS…THE HERALD ANNOUNCES THE END OF HOURLY PROCESSION

LIFT ASCENDING INSIDE THE CLOCK TOWER

CHURCH OF OUR LADY IN FRONT OF TÝN, SEEN FROM CLOCK TOWER

ACROSS THE SQUARE TO THE TOMB STONE OF TYCHO BRAHE ...

ACROSS THE SQUARE TO THE TOMB STONE OF TYCHO BRAHE ...

ACROSS THE SQUARE TO THE TOMB STONE OF TYCHO BRAHE ...

Interestingly there is no symbolical reference to his interest in astronomy

Wikipedia advises that the modern tomb stone lies in the Church of Our Lady in front of Týn, this dates from 1901.What it does not say is that the original stands next to it.

Nasal prosthesis depicted is realistically sculpted.

TYCHO BRAHE’S TOMB STONE

1563 conjunction of Jupiter & Saturn was observed by Tycho – dismayed at incaccuracy of existing tables:•13th century Alphonsine tables were out by a month•modern Prutenic tables (based on Copernican model) were out by 2 daysHe had the means and motivation to improve on this.

TYCHO BRAHE

Granted lordship of island of Hven (now in Sweden), Constructed the observatory of Uraniborg from the Greek word Urania, muse of astronomy and goddess of the heavens.

Lavishly equipped with scientific instruments of an accuracy never seen before.A two-man operated sextant which could measure angles to within 1 minute (1/60th of a degree). 1577 Successfully proved that comets were not METEROLOGICAL (in the

atmosphere using parallax, moreover proved comet was moving between planets – Aristotelian spheres did not exist!

‘Inside every astronomer there lurks a cosmologist’ Michael Hoskin Cambridge Illustrated History of Astronomy.

The Tychonic System proposed the Sun and Moon go around the earth, while all the other planets go around the sun.

Having seen the statue using on-line guides to Prague I was determined to find it but wary that it was so far away from the tourist areas.

STATUE OF TYCHO BRAHE & JOHANNES KEPLER

In the event, the tram from our hotel went straight to it (No.22)

Tycho quit his island in 1597 as the new king of Denmark Christian IV cut his funding.

Tycho is invited to Prague by the Holy Roman Emperor Rudolph II and given the castle of Benatky. Kepler responds to invitation.

‘At last, then, on 4 February 1600, Tycho de Brahe and Johannes Keplerus, co-founders of a new universe , met face to face...’ Arthur Koestler The Sleepwalkers

TYCHO BRAHE & JOHANNES KEPLER

Shortly after meeting de Brahe in Prague Kepler wrote:‘Tycho possess the best observations and thus so to speak the material for the building of the new edifice...he only lacks the architect who would put all this to use according to his own design...he is obstructed in his progress by the multitude of the phenomena and the fact that the truth is deeply hidden in them’

A bold statement of intent !

Their association in Prague lasted just 18 months over which time they fell out regularly, Kepler requesting better pay and conditions, irritated by the insults of Jepp, Brahe’s sinister dwarf and his place at table.

Brahe was frustrated by the failure of several key assistants from Hven to show up, by court officials failing to meet financial pledges of Rudolph II, poor progress in building a new Urnaiborg at Benatky and by Kepler’s poor social skills.

Brahe died in 1601 of complications arising from failure to excuse himself at the right time from an illustrious meal. Kepler succeeded him as Imperial Mathematicus to Rudolph II.

TYCHO BRAHE & JOHANNES KEPLER

As Kepler worked on, progress did not come easily. Early on adjusted for the movement of the earth by using measurements of Mars at opposition, when Mars appears the same as it would from the Sun.

Knowing that a discrepancy of 8 arc minutes had to be from nature and not an observational discrepancy, he stuck with Tycho’s data.

Allan Chapman marks this as the point at which answers were sought through addressing nature direct rather than pursuing prior notions of philosophy (principally Greek in origin) . Arthur Koestler goes further:“This new departure determined the climate of European thought in the last three centuries, it set modern Europe apart from all other civilisations in the past and present, and enabled it to transform it’s natural and social environment as completely as if a new species had arisen on this planet.”Lacking the knowledge of the physical laws at work and their geometrical manifestation, Kepler would perform the same calculation over and over, lamenting to the reader of 70 repetitions. He worked on the theory of an egg-shaped orbit for a whole year of his life before starting again from scratch. Eventually the numbers tumbled into place with elliptical orbits.

WHAT KEPLER ACHIEVED IN PRAGUE

Kepler’s astrological predictions proved startlingly accurate on at least two occasions.He took his responsibilities very seriously, not to exploit his emperor's ‘human credulity’Kepler’s obsession with a cosmos built around the Pythagorean solids and the musical harmonies was not quite as extravagant as it seems to us... It was in keeping with the traditions of Neoplatonism, with the revival of Pythagorianism, with the teaching of Paracelsians, Rosicrucians, astrologers, alchemists, cabbalists and hermetists who were still conspicuously in evidence in the early seventeenth century. Arthur Koestler

THE ULTIMATE PARADOX: FOUNDATION OF SCIENCE BORN OF MYSTICISM

The astrologers home under the walls of Prague Castle. The lady who lived here was tortured to death by the Gestapo for predicting a short end to the Nazi occupation of Czechoslovakia.

THE ULTIMATE PARADOX: FOUNDATION OF SCIENCE BORN OF MYSTICISM

The Alchemists home, under the walls of Prague Castle.Note his bed is in his laboratory.

Kepler stayed in Prague from 1601 to 1612, by far the most fruitful period of his life.Kepler published his seminal work ‘Astronomia Nova’ from Prague in 1609, announcing his first two laws of planetary motion.He also published ‘Optics’ in 1604, founding another new science.Combining his discoveries with the Pythagorean idea of the harmonies of the spheres, Kepler’s masterpiece, Harmonice Mundi, or Harmonies of the World was published in 1619.The first to appreciate the significance of Kepler’s work were all British – Edmund Bruce, Thomas Harriot, Rev John Donne, Jeremiah Horrocks and Newton.

KEPLER AT WORK ON THE NEW DATA

Harmonice Mundi: "…to bare the ultimate secret of the universe in an all embracing synthesis of geometry, music, astrology, astronomy and epistemology (nature of knowledge). It was the first attempt of this kind since Plato and it is the last to our day. After Kepler, fragmentation of experience sets in again, science is divorced from religion, religion from art, substance from form, matter from mind.“ Arthur Koestler, The Sleepwalkers.

A last word from Allan Chapman on cosmology and the science of the mind : “It is often religion’s scientific critics who most often behave like fundamentalists today...when scientists who study these challenging and thought provoking subjects refuse as a point of creedal allegiance to consider, even hypothetically, any form of non-physical explanation in the understanding of nature, then they cease to display that intellectual openness which all scientists generally accept as the hallmark of their profession..“ Allan Chapman, Gods in The Sky 2001

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