Rome, Zanetti for Joannes Paulus Gellius, 1607, 4to, Contemporary limp vellum, manuscript title on spine, printed title in red and black and with large woodcut of an armillary sphere, woodcut diagrams and illustrations in text, woodcut tail-pieces and decorative initials, contemporary ink marginalia throughout and notes to endpapers, occasional discolouration to text but overall a very attractive copy.
Clavius (1538-1612), a member of the Jesuit order, was one of the most respected astronomers in Europe. He was the main architect of the Gregorian calendar (which we use today), and his astronomical textbooks were widely used for over fifty years. His commentary on the “Sphaera” of Sacrobosco, demonstrates his adherence to the geocentric model of the universe.
An Extraordinary Copy with six pages of contemporary notes to the endpapers by the Jesuit Astronomer Orazio Grazzi, mostly relating to the Supernova of 1604, known as ‘Kepler’s Supernova’; discussions with the Austrian Jesuit Roman astronomer Christoph Grienberger about his observations of the same Supernova; and the writer’s correspondence with Clavius. Numerous annotations throughout the text. References to other Astronomers such as Archimedes; Albumasar, one the most renowned astronomers of the middle-ages and others.
It is fairly certain that the author of the notes was the Jesuit Astronomer Orazio Grazzi of the Collegio Romano, who also had a long running dispute with Galileo.
The Supernova 1604 has long been referred to as “Kepler’s Supernova,” after astronomer Johannes Kepler, who was one of the first to observe it. “Brighter than all other stars and planets at its peak, it was observed by the German astronomer, who thought he was looking at a new star. What Kepler saw was actually an exploding star. This supernova posed a challenge to seventeenth-century astronomers, who found themselves observing something that contradicted all conventional wisdom about the cosmos.
The 1604 supernova was the last one recorded in the Milky Way to date.
SN 1604, also known as Kepler’s Supernova, Kepler’s Nova or Kepler’s Star, was a Type la Supernova that occurred in the Milky Way, in the constellation Ophiuchus. Appearing in 1604, it is the most recent supernova in our galaxy to have been unquestionably observed by the naked eye, occurring no farther than 6 kiloparsecs (20,000 light-years) from Earth. Prior to the adoption of the current naming system for supernovae, it was named for Johannes Kepler, the German astronomer who described it in De Stella Nova.
Visible to the naked eye, Kepler’s Star was brighter at its peak than any other star in the night sky, with an apparent magnitude of −2.5. It was visible during the day for over three weeks. Records of its sighting exist in European, Chinese, Korean and Arabic sources.
Johannes Kepler’s original drawing from De Stella Nova (1606) depicting the location of the stella nova, marked with an N (8 grid squares down, 4 over from the left).
It was the second supernova to be observed in a generation (after SN 1572 seen by Tycho Brahe in Cassiopeia). No further supernovae have since been observed with certainty in the Milky Way, though many others outside our galaxy have been seen since S Andromedae in 1885. SN 1987A in the Large Magellanic Cloud was visible to the naked eye.
Evidence exists for two Milky Way supernovae whose signals would have reached Earth c. 1680 and 1870 – Cassiopeia A, and G1.9+0.3 respectively. There is no historical record of either having been detected in those years probably as absorption by interstellar dust made them fainter.
The remnant of Kepler’s supernova is considered to be one of the prototypical objects of its kind and is still an object of much study in astronomy.
Astronomers of the time (including Kepler) were concerned with observing the conjunction of Mars and Jupiter, which they saw in terms of an auspicious conjunction, linked in their minds to the Star of Bethlehem. However, cloudy weather prevented Kepler from making any celestial observations. Nevertheless, his fellow astronomers Wilhelm Fabry, Michael Maestlin and Helisaeus Roeslin were able to make observations on 9 October, but did not record the supernova. The first recorded observation in Europe was by Lodovico delle Colombe in northern Italy on 9 October 1604. Kepler was only able to begin his observations on 17 October while working at the imperial court in Prague for Emperor Rudolf II. The supernova was subsequently named after him, even though he was not its first observer, as his observations tracked the object for an entire year. These observations were described in his book De Stella nova in pede Serpentarii (“On the new star in Ophiuchus’s foot”, Prague 1606).
In Kepler’s De Stella Nova (1606), he criticised Roeslin concerning this supernova. Kepler argued that in his astrological prognostications, Roeslin had picked out just the two comets, the Great Comet of 1556 and 1580. Roeslin responded in 1609 that this was indeed what he had done. When Kepler replied later that year, he simply observed that by including a broader range of data Roeslin could have made a better argument.