The Orion Nebula and Sirius

Galileo’s Sidereus Nuncius (Venice, 1610), was the first to attempt a naturalistic rendering of the Orion constellation. In the following illustrations, taken from Worth’s two editions of Sidereus Nuncius we see two completely different methods of rendering it. The first is taken from an English 1683 copy of Pierre Gassendi’s edition of Sidereus Nuncius and shows the stars against a black background.

 

Galileo Galilei, Sidereus Nuncius (London, 1683), plate.

 

The second is from Worth’s three volume Florentine edition of Galileo’s works and portrays the same information in a totally different way.

 

Galileo Galilei, Opera (Florence, 1718) vol 2, p. 20.

It was, however, Nicolas-Claude Fabri de Peiresc, 1580-1637, to whom credit is given for discovering the nebula, a misty expanse in the sword of Orion, on 28 November 1610. Another reference to it was made eight years later by the Jesuit astronomer Johannes Baptist Cysat, 1587-1657, who placed it in the last star of Orion’s belt – rather than as a small cloud around the second star. The first representation of the nebula itself was in Huygen’s 1659 Systema Saturnium – a reproduction of which may be found in Worth’s 1724 of Huygen’s works:

 

Christiaan Huygens, Opera varia (Lyon, 1724), vol 2, p. 524.

Here we see that Huygens (who genuinely believed that he was the discoverer of the nebula) places seven stars within it. Harrison (1984) suggests that the few sightings of Great Nebula M42 prior to Huygens may perhaps be due to it lacking sufficient brightness to be clearly visible.

Sirius

 

Stanisław Lubieniecki, Theatrum cometicum (Amsterdam, 1668), detail of Canis Maior constellation.

In this detail from an illustration in Worth’s copy of Stanisław Lubieniecki, Theatrum cometicum (Amsterdam, 1668), we see his depiction of the constellation Canis Major of which Sirius was perhaps the best known star. Sirius had attracted relatively little attention but Worth had the major work on the subject: John Bainbridge’s posthumous Canicularia was published by John Greaves at Oxford in 1648.

John Bainbridge, Canicularia (Oxford, 1648), title page.

Bainbridge, 1582-1643, had been appointed Savilian Professor of Astronomy at Oxford in 1620. In the same year he published an edition of Ptolemy’s Planetary Hypotheses but it is clear from his lecture notes that he was not a follower of the Ptolemaic cosmology. His work on the Dog Star, published by his successor as Savilian professor, John Greaves, 1602-1652, was principally concerned with the application of ancient observations of the stars in the field of chronology – an area of interest to Worth, judging by his purchase of Arthur Bedford’s Scripture Chronology demonstrated by astronomical calculations (London, 1730) and William Whiston’s Astronomical principles of religion (London, 1717). It likewise fitted in well with William Whiston’s Astronomical lectures read in the public schools at Cambridge (Cambridge, 1715) and his other works on university teaching of astronomy such as David Gregory’s Astronomiae, physiciae & geometricae elementa (Oxford, 1702) is unclear. Beyond Bainbridge’s predominantly chronological treatment, Sirius does not appear to aroused much interest in the early modern astronomical community – apart from the odd description of its possible size. This facet of the seventeenth century debate is echoed in the following paper, read by Francis Robartes, ?1650-1718, to the Dublin Philosophical Society in 1693 which uses the example of Sirius to discuss the vexed question of the distance of the fixed stars:

‘Now since in all likelihood the fixed stars are suns (perhaps of a different magnitude) we may as a reasonable medium presume they are generally about the bigness of our sun. Let us then (for example) suppose the Dog Star to be so. The distance from us to the sun being about 100 times the sun’s diameter (as is demonstrable from the sun’s apparent diameter being 32 minutes), it is evident that the angle under which the Dog Star is seen in Mr Hugen’s telescope, must be near the same with the angle of its parallax to the sun’s distance, or semidiameter of the earth’s annual course; so that the parallax to the whole diameter can be but double such a quantity as even to Mr Hugens’s nice observation is altogether insensible. The distance therefore of the fixed stars seems hardly within the reach of any of our methods to determine, but from what has been laid down, we may draw some conclusions that will much illustrate the prodigious vastness of it.’*

Selected Reading

*Quotations marked with an asterisk may be found in Hoppen, K. T. (ed.) (2008) Papers of the Dublin Philosophical Society 1683- 1709 (Dublin: Irish Manuscript Commission), 2 vols. Apt, A. J . (2004). ‘Bainbridge, John (1582-1643), astronomer and physician’, ODNB. Harrison, T. G. (1984). ‘The Orion Nebula: Where in History is it?’, Royal Astronomical Society Quarterly Journal 25, no. 1, 65-79.