Michael Maestlin and the New Star of 1572

Copernicus's De revolutionibus (1543) was not in 1572 one of these factors of criticism, Copernican heliocentrism being almost universally interpreted as a geometrical, counterfactual hypothesis to ‘save the phenomena’ of planetary motion by means of geometrical calculation. See Westman Robert S. , “The Melanchthon circle, Rheticus and the Wittenberg interpretation of the Copernican theory”, Isis, lxvi (1975), 165–93.

The earliest trustworthy date for the appearance of the nova seems to have been 5 November, when Francesco Maurolyco reported his observation of the star in an unpublished report written the following day. See Hellman C. Doris , “Maurolyco's ‘lost’ essay on the new star of 1572”, Isis , li (1960), 322–36. References to an earlier date of appearance in October (e.g. in E. Camerarius, Observatio et descriptio novi sideris, quod forma primae magnitudinis apparuit, principio Octobris Anno Christi 1572. ac per integrum fere Annum conspicuum fuit, vsque in September Anni praesentis 1573. adhuc in magnitudine tertia splendet (Frankfurt an der Oder, 1573)) seem to have no warrant.

This idea was clearly expressed by Tycho Brahe in his treatise on the nova. See De nova stella (1573), in Tycho Brahe, Opera omnia, ed. by Dreyer J. L. E. (Copenhagen, 1913–29), i, 19: The star was a prodigy “nunc demum advesperascenti mundo exhibitum”. In what follows, we refer to this edition as TBOO followed by the number of the volume; line numbers are given after the page numbers.

See Barnes Robin B. , Prophecy and gnosis: Apocalypticism in the wake of the Lutheran Reformation (Stanford, CA, 1988); Granada Miguel A. , “Cálculos cronológicos, novedades cosmológicas y expectativas escatológicas en la Europa del siglo XVI”, Rinascimento, 2nd ser., xxxvii (1997), 1997–435.

Most famous and widely diffused was the poem by Theodore Beza, Calvin's successor in Geneva. Beza's poem was reproduced by Tycho in his Astronomiae instauratae progymnasmata (published posthumously in 1602), TBOO, ii, 326. Long poems were written and published in French by Guy Le Fèvre de la Boderie (Cantique sur la nouvelle estoille (Paris, 1574)) and in Latin by the German Nicodemus Frischlin (Consideratio nouae stellae (Tübingen, 1573)). Frischlin's booklet included Maestlin's Demonstratio astronomica, which is the subject of the present article.

For an incomplete census of tracts written on the nova see Hellman C. Doris , “The gradual abandonment of the Aristotelian universe: A preliminary note on some sidelights”, in Mélanges Alexandre Koyré: L'aventure de la science , i (Paris, 1964), 283–93; eadem, “The new star of 1572: Its place in the history of astronomy”, in Actes du IXe Congrès d'Histoire des Sciences: Barcelona-Madrid 1–7 Septembre 1959 (Barcelona and Paris, 1960), ii, 482–7; and Granada , “Cálculos cronológicos” (ref. 4). A very valuable study on the publications concerning the nova has been published recently by Michael Weichenhan, “Ergo perit coelum…”: Die Supernova des Jahres 1572 und die Überwindung der aristotelischen Kosmologie (Stuttgart, 2004). Strangely enough, the author pays little attention to Maestlin and offers no analysis of his important treatise on the nova.

Frischlin's poem, addressed to Prince Friedrich von Württenberg, extended over pp. 1–26 and was the chief content of the edition. It followed the dedicatory letter by the same Frischlin (pp. A2r—v), dated Christmas 1572. Nicodemus Frischlin (1547–90) was professor of poetry and history at Tübingen from 1567 to 1582 and occasionally taught astronomy, during the absence of Philippus Apianus (1531–89), the appointed professor, in 1569–70 and 1571–72. See Methuen Charlotte , Kepler's Tübingen: Stimulus to a theological mathematics (Aldershot, 1998), 118–29, and Weichenhan , op. cit. (ref. 6), 532–8.

TBOO, iii, 58–62 (Maestlin's treatise), 62–67 (critical commentary).

See Zwischen Copernicus und Kepler –- M. Michael Maestlinus Mathematicus Goeppingensis 1550–1631: Vorträge auf dem Symposium, veranstaltet in Tübingen vom 11. bis 13. Oktober 2000 , ed. by Betsch G. Hamel J. , Acta historica astronomiae, xvii (Frankfurt, 2002), 9. See also Jarrell Richard A. , “The life and scientific work of the Tübingen astronomer Michael Maestlin 1550–1631”, Ph.D. thesis, University of Toronto, 1972, 19f., 23.

De stella nova, TBOO , i, 19. 29–36: “Quapropter etsi de hoc nouo & nunc primum nato sidere, aliqua in medium adferre constituerim: Tamen de eius generatione, & quibus rationibus extiterit, me nihil affirmare posse, ingenue fateor: Sed solum ea, quae ad Mathematicam considerationem spectant excutiam. Dicam enim de eius, quo ad fixas & Zodiaci longitudinem, latitudinemque positu: De ipsius a Terra, centro Universi, remotione: Nec non de eiusdem magnitudine, lumine & colore.” Significantly, Tycho makes explicit his conviction that the distance of the new star with respect to the centre of the world is the same as its distance to the Earth, given his geocentric and geostatic conviction. Contrarily, Maestlin speaks only of the distance of the new star with respect to the centre of the world, omitting his opinion (presented with some detail and argument in the treatise) that it is the Sun that occupies the central place in the universe; that is, his adoption of Copernican cosmology as a true description of the world structure. According to his programme, Tycho presents in three successive chapters “The position of this new star in heaven with respect to the fixed [stars] and its longitude and latitude with respect to the Zodiac” (20–24), “Its position with respect to the diameter of the world and its distance to the Earth, the centre of the universe” (24–28), and “Its magnitude, light and colour” (28–30). This last question was also treated by Maestlin in several instances in the course of his treatise; see the reprint in Tycho's Progymnasmata, TBOO, iii, 58. 23–30; 59. 14–15; 60. 29–32 (and below, Appendix, Text 1, where we reproduce Maestlin's treatise with an indication of the pages in the original edition and in the Progymnasmata).

De stella nova, TBOO , i, 19. 37–40, after the text quoted in ref. 10: “quibus etiam de hujus stellae effectibus, ab Astrologia petitas coniecturas subiungam”; and ibid., 30–34 (“Astrological judgement on the effects of this recently born star”). His programme in the Progymnasmata adopted an identical concession. After an extended exposition of purely observational and geometrical character, the Conclusion (TBOO, iii, 304–19) suddenly gave way to a brief and purely ‘conjectural’ digression on the generation of the star and its exceptional significance in the final period of the existence of the world.

“Quid uero Noua haec Stella portendat, aliis disputandum relinquemus: Nobis enim tantum illa, quae Astronomus Veritatis amans, de ea pronunciaret, conscribere placuit”, Progymnasmata, TBOO , iii, 62. 18–20. As we shall see below, in the printed version Maestlin added important passages in which he expressed his opinion on the supernatural (“ab hyperphysica causa”) origin of the nova.

“Because he rejects astrological [considerations], which is prudently done in my judgement, he releases me, who am likewise willingly abstaining from this, from the usual excuse” (“Cumque is Astrologicam ipsemet detrectet (quod & prudenter factum iudico) me alias istiusmodi libenter supersedentem, solita excusatione liberat”, TBOO, iii, 67. 16–18).

Frischlin N. , Consideratio nouae stellae (ref. 5), 6, verse 25–7, verse 6: “Aduentum reducis denotat illa Dei. / Quando senescenti nunc imminet vltima mundo / finis, & extremae tempora lucis eunt. / Tempora lucis eunt: Summo qua Christus Olympo / damnatum veniet vindice mente reos. / Infidosque homines Stygium detrudet ad orcum: / Illic vt poenas, quas meruere, luant. / Aeternaque pios requie ditabit Olympi: / Et faciet granis horrea plena suis. / Nam si vera tibi verbis fateamur oportet: / Auguror extremum non procul esse diem. / Quando sui reditus ipse olim talia Christus / signa dedit, mundi fata suprema canens.” The nova announces then that the coming of the Son of Man (foretold by Christ himself in the Gospel; Frischlin mentions Mathew 24 and Luke 21) before the last day is already at hand. Beyond this clearly eschatological significance, common astrological predictions such as the menaces the nova portends to septentrional peoples and states (Frischlin, Consideratio nouae stellae, 6, verses 13–24) according to its northern latitude are of minor importance. On the interpretation of the nova by Frischlin, see Weichenhan, op. cit. (ref. 6), 532–8.

See below our edition of the manuscript version in Appendix, Text 1, 2v. We treat this question more fully below.

“Luna … terris proxima, quando secundum Copernicum abest 521/4 semidiametris terrae, pariat parallaxin 63 minutorum, sed altissima, quando eius distantia 68 1/3 semidiametrorum terrae, commutet apparentem motum a uero 48 minutis. Vt uidere licet in tabulis Prutenicis et Copernici. Quod si Luna tantam procreat parallaxin, multo maiorem efficeret Astrum hoc nouum, si in Elementari regione esset, vtpote centro terrae vicinius: Vt Purbachius asserit“, Maestlin, Demonstratio astronomica, in TBOO, iii, 59 and below, Appendix, Text 1; here and in successive quotations, italics indicate an addition in the printed edition with respect to the first manuscript version. Cf. also ref. 77.

For an exposition on Tycho's explanation of the new star in his De stella nova, see Dreyer J. L. E. , Tycho Brahe: A picture of scientific life and work in the sixteenth century (Edinburgh, 1890), 38–56; Thoren Victor E. , The Lord of Uraniborg: A biography of Tycho Brahe (Cambridge, 1990), chap. 4; Granada , “Cálculos cronológicos” (ref. 4), 391–5; and Weichenhan , “Ergo perit coelum…” (ref. 6), 591–9.

“… patet noui huius luminis apparitionem non a naturali causa dependere…. Quid ergo prohibet quin dicamus, totum hoc hyperphysicum…[?]”, TBOO, iii, 60 (for the question mark see below ref. 28). For a similar account in Tycho, see De stella nova, TBOO, i, 15–19, esp. 19. 19–24.

“Ex dictis patet noui huius luminis apparitionem … nec Cometam, sed potius, stellam nouam dicendam esse: Nisi Cometas non tantum in elementari regione, sed etiam in orbe stellato … generari posse, adeoque coelum generationis & corruptionis, contra Aristotelem omnesque Physicos & Astronomos, non expers esse, dicere velimus”, TBOO, iii, 60. Tycho Similarly , De stella nova, TBOO, i, 27. 38–42.

In his treatise, Maestlin (and the same applies to Tycho in the De stella nova) accepts without hesitation the existence of the heavenly spheres. In his richly annotated copy of Copernicus's De revolutionibus (now in Schaffhausen Stadtbibliothek), Maestlin wrote in the left margin of Osiander's Praefatiuncula ad Lectorem: “In coelo orbes revera esse testatur perfectissima regularitas vel ordinatissima anomalia motus corporis perfectissimi, item calculi ex illis orbibus admiranda concordia, quae certe numquam tanta praecisione corresponderit nisi orbibus coelum moveretur” (“That there are indeed celestial spheres is attested by the very perfect regularity or by the very orderly anomaly of the motion of the most perfect body; likewise by the most admirable agreement of the calculations from these spheres, which would surely never match with so much precision unless the heavens are moved by spheres”); see Gingerich O. , An annotated census of Copernicus' De revolutionibus (Nuremberg, 1543 and Basel, 1566) (Leiden, Boston and Cologne, 2002), 218 and 222 (translation by Gingerich modified). As stated by Gingerich, Maestlin bought his copy in 1570 and although the annotations are undated, it can reasonably be assumed that he began to annotate it immediately afterwards (ibid., 220). Thus, we can suppose that the above quoted annotation, along with the other annotation that we quote below, preceded the writing of the treatise on the nova.

“Quibus tamen obseruationibus omnibus idem in octaua sphaera locus, nec vnico scrupulo toto hoc tempore, quo obseruari coepit, vel differens vel mutatus, depraehensus est” ( TBOO , iii, 59); “Quod idem scintillans lumen eius, a quo plerique Planetae immunes sunt, attestatur” (ibid., 60). For the same argument in Tycho, see De stella nova, TBOO, i, 27–28.

De stella nova, TBOO , i, 27. 19–37: “But that this is not in the orb of Saturn, nor that of Jupiter, nor that of Mars, nor those of the other planets, is clear from this, that in the space of the six months that have now passed it has not by its own motion advanced by one minute from that place in which we first saw it, which ought to have occurred if it were in a planetary orb. For it would be moved by the motion peculiar to that orb, contrary to the course of the primum mobile…. Whence if this star were in an orb of the seven planets, it would necessarily be led around with that orb, to which it was affixed, contrary to the diurnal rotation. And this motion would be noticed in such a great span of time even in the case of the slowest advance, that of the orb of Saturn, even without every instrument looking. Wherefore this star has its place neither in the elemental region below the Moon, nor in the orbs of the seven planets, but in the eighth sphere among the rest of the fixed stars. Q E D” (“Quod autem nec in orbe Saturno, nec Iovis, Martisve, aut aliorum Planetarum existat, hinc patet, quod elapso iam sex mensium spacio, nullo minuto ab eo loco, in quo primum eam conspeximus, motu proprio progressa est, quod fieri oportebat si in aliquo Planetarum orbe esset. Moveretur enim motu ipsius orbis peculiari, contra primi mobilis rationem…. Unde si haec stella in aliquo orbium septem errantium siderum constitueretur, necesario cum ipso orbe, cui affixa esset, contra diurnam revolutionem circumduceretur. Atque hic motus etiam in lentissimo Saturni orbis progressu tanto temporis intervallo, etiam absque omni instrumento intuenti animadverteretur. Quapropter haec stella nova nec in Elementari infra Lunam, nec in orbibus septem errantium siderum, sed in octava sphaera inter reliquas fixas locum habet, quod erat demonstrandum”). See Granada Miguel A. , “Did Tycho eliminate the celestial spheres before 1586?”, Journal for the history of astronomy, xxxvii (2006), 125–45, pp. 132f.

“Animaduertimus autem, quod nullius, ne tardissimi Planetarum motum sequatur, sed simplicissimo diurno, sicut et stellae fixae … eundem subinde positum ad illas retinens circumferatur: quod nullo modo fieret, si orbi alicuius Planetae affixa esset, nam vt videre licet 5. lib. Coper. commutationis motu expers non esset. Vnde manifestum est, stellam hanc longe super omnes planetas eleuatam, adeoque inter fixas stellas in firmamento repositam esse”, TBOO, iii, 59–60. For Copernicus's reference to the ‘motus commutationis’ in the superior planets, see De revolutionibus, V, chaps. 1 and 3, fol. 133v–134, 141r—v (cf. the English translation, N. Copernicus, On the revolutions, transl. and commentary by Rosen E. (Baltimore and London, 1992), 227f., 240f.; Rosen accurately translates ‘motus commutationis’ as ‘parallactic motion’). It is worth mentioning that in his copy of De revolutionibus, Maestlin underlines in these chapters the sentences mentioning the motion of the Earth: “Nam motum commutationis nihil aliud esse dicimus, nisi eum in quo motus terrae aequalis illorum motum excedit, ut in Saturno, Ioue, Marte: Uel exceditur, ut in Venere & Mercurio” (fol. 134); “Haec & similia nobis occasionem praestiterunt de mobilitate terrae … cogitandi” (fol. 140v). Maestlin has written in the margin of fol. 141 (chap. 3): “Aliud argumentum quod terrae mobilitatem confirmat.” For Maestlin's annotations on this chapter, see Westman Robert S. , “Michael Mästlin's adoption of the Copernican theory”, Studia Copernicana, xiv (1975), 53–63, p. 61.

“Verum vero consonat et ex vero non nisi verum sequitur”, Gingerich, An annotated census of Copernicus' De revolutionibus (ref. 20), 222 (his translation).

“Cum autem immensa sit altitudo orbis stellati, quae quousque se extendat non constat, ad quam etiam inter Solem et terram distantia incomparabilis est, ut testatur Copernicus (Astronomorum post Ptolemaeum Princeps) libro 1 cap: 6. et lib: 3 cap: 15” (see Appendix, Text 1, 1v). The printed version reads: “Quoniam immensa est altitudo orbis stelliferi, quae quousque se extendat, non constat, ad quam, quae inter solem et terram est distantia concerni nequit (vt testatur Copernicus, Astronomorum post Ptolomaeum princeps, qui omnium orbium planetarum certas distantias a centro mundi demonstrans, in orbe stellato subsistit)”. The expression “Astronomorum post Ptolomaeum Princeps” is present in Maestlin's annotation to Copernicus's Preface to the Pope (fol iiij), together with his adherence to Copernican cosmology: “Nisi ergo usitatas hypotheses reformatas videam … approbabo ego hypotheses et opinionem Copernici, post Ptolemaeum omnium Astronomorum principis”; see Gingerich , An annotated census of Copernicus' De revolutionibus (ref. 20), 223. In the above mentioned chapters Maestlin underlined in his copy of the De revolutionibus the passages alluded to: “Nihil enim aliud habet illa demonstratio, quam indefinitam caeli ad terram magnitudinem. At quousque se extendat haec immensitas minime constat” (I, 6, fol. 4v); “si fuerit, ut diximus, inter Solem & terram distantia, quae ad immensitatem stellarum fixarum sphaerae non possit aestimari” (III, 15, fol. 84v). See also below ref. 80.

See Progymnasmata, TBOO , iii, 63. 6–9: “Sic etiam commutationis motus immunitas, non satis probat eam [stellam] ultra Planetarum terminos remotam fuisse, nisi cum Copernico statuere velimus, Terram annuatim convolvi, quod adhuc longe maiore probatione indiget”; 63. 35–39: “Verum quod Affixarum Stellarum Orbem, Copernici imitatione, adeo vastis interstitiis ultra Saturni Sphaeram removet, ut spacium illud, quod est a Sole ad nos, eius respectu insensibile evadat; non antea ita se habere persuadebit, quam Solem in centro Universi revera quiescentem, Terramque circa hunc anniversarie convolvi, evicerit” (our italics). On the irrationality and lack of harmony of the Copernican void and distribution of heavenly bodies, see ibid., the following lines.

Maestlin's Copernicanism in 1572 was suggested by Robert S. Westman in his article “Michael Mästlin's adoption of the Copernican theory” (ref. 23), 61, mostly through evaluation of Maestlin's annotations to Copernicus's book. Surprisingly, he did not profit sufficiently from evidence provided by the treatise on the nova.

“Rationem non video, nisi quod forsitan ab hyperphysica causa exortus eorum dependeant. Quid ergo prohibet quin dicamus, totum hoc hyperphysicum, stellamque hanc nouam a summo creatore his nouissimis temporibus creatam esse, atque vti miraculose coepit, ita miraculose desituram, cuius vtriusque causa omnem humanum captum effugiat [?]”, printed edition, TBOO, iii, 60. We add the question mark, omitted in both printed editions.

See Granada , “Cálculos cronológicos” (ref. 4), 385–7.

“Sed haec piis nova esse non convenit, cum Salvator noster iam olim, ista nostris his seculis eventura praedixerit, quando ait: Erunt signa in Sol & Luna & stellis, commovebuntur virtutes coelorum, obscurabitur Sol, & Stellae de coelo cadent &c. Quibus non tantum nos exuscitare vult, ut veterno excusso curemus, ne gloriosus ultimi adventus sui dies nos incautos & oscilantes opprimat…. Hoc Salvatoris nostri vaticinium, iam certe plus quam satis completum esse nemo sanus & pius dubitare potest”, Maestlin M. , Consideratio & observatio Cometae aetherei astronomica, qui anno MDLXXX. … apparuit (Heidelberg, 1581), sig. B1 r—v.

“Dubium nemini esse debet, adesse ineluctabile fatum…. Ad te igitur, bone Iesu, toto pectore confugimus, illumina & rege corda nostra…. Et veni cito abrupturus mundum, desideramus rumpi horum malorum catenam … desideramus te in aeternum videre, & aeterno gaudio sanguine tuo parto tecum frui. Amen”, ibid., sig. F2 r—v. In the same vein, Maestlin proclaimed in his treatise against the reform of the calendar by Pope Gregory XIII (1582) his firm belief in the near end of the world. See Maestlin M. , Ausführlicher Bericht von dem allgemeynen Kalender … (Heidelberg, 1584), 16 v: “So ists doch gewiss, dass wir von der Welt End nicht fern sind”. Cf. also J. Hamel, “Die Rolle Michael Mästlins in der Polemik um die Kalenderreform von Papst Gregor XIII”, in Zwischen Copernicus und Kepler (ref. 9), 33–63, pp. 48f.

Methuen Charlotte , “‘This comet or new star’: Theology and the interpretation of the nova of 1572”, Perspectives on science, v (1997), 499–515.

Ibid., 501f.

Ibid., 502, note 6.

Ibid., 502.

To this purpose, we have integrated the archive sources examined by Methuen (Württenbergisches Hauptstaatsarchiv in Stuttgart, dossier A274 Bü 21) with a thorough examination of the records concerning Wilhelm IV in the State Archive in Marburg (Hessisches Staatsarchiv Marburg). The copy in Stuttgart seems to be Maestlin's manuscript.

See below Appendix, Text 2.

This letter to Wilhelm IV by August, Prince Elector of Saxony, is not preserved in the State Archive in Marburg. Most probably a copy is present in the Sächsisches Hauptstaatsarchiv in Dresden.

Wilhelm IV to August of Saxony (3 December 1572) in the State Archive, Marburg (Bestand 4f Kursachsen 51). This is a note (‘Zettel’) in the letter, dated 3 December, but sent the following day after the observation of the star.

“Wiewol wir E. L. [Euer Liebden] gestern morgen [3 December] geschrieben, das wir keinen Cometen oder Meteoron vermercktt hetten, wie wir dan auch ein zeitlang vonn wegen obliegender gescheffte kein sondere achtung vffs gestirn gegeben, So haben wir doch vff E. L. schreiben gestern abentt da es recht ezwas hell wahr den himmel angesehen, vnnd einen grossen hellenn stern bei der Constellation Cassiopeye vngefehr in der grosse des morgen sterns gesehen welches gewißlich kein naturliches stern ist” (“Although we informed Your Grace yesterday morning [3 December] that we had observed no comet or meteor, as we had of late given no particular attention to the sky due to our present obligations, nevertheless we observed the heavens yesterday evening, following Your writing, because it was truly clear, and saw a great bright star in the constellation of Cassiopeia, approximately as great as the morning star, which certainly cannot be a natural star”), Wilhelm IV to August of Saxony (4 December 1572), in the State Archive, Marburg (Bestand 4f Kursachsen 51). It is a new note (also entitled ‘Zettel’), dated 4 December and reporting the observation from the preceding night. We intend to publish these reports in a future study.

These letters, which we intend to publish in the near future, will modify and complete the account given by Tycho in Progymnasmata, TBOO , iii, 113–32.

“So haben wir daruber bei den Astronomis vnnserer hohenschul zu Tuvingen bericht einnemmen lassen, die vnns dißer tagen denselben ex fundamentis astronomicis gethon, wie E: L: Vsser beigethonen copiis freundtlich vnnd bruederlich zuvernemmen haben.” See below, Appendix, Text 2.

Methuen , “‘This comet or new star’…” (ref. 32), 501.

The German report by Apianus is dated 26 December. It was published by Tycho in Progymnasmata, TBOO , iii, 158–61 in Latin translation. It was addressed, however, not to Wilhelm IV, as Tycho pretends (ibid., 157f.), but to Ludwig of Württemberg. Tycho also omitted a long section on the astrological effects of the nova at the end of Apianus's treatise.

Hessisches Staatsarchiv Marburg, Bestand 4f Kursachsen 51, letter by Ludwig of Württemberg, 29 December 1572. The text presents only very slight differences between the two versions.

See below, Appendix, Text 3: “Wir habenn E. L. schreibenn de dato Vrach dem 29 Decembris benebenn E. L. Astronomorum zu Thubingen beygefugtem bedencken des vngewonlichen Sterns halben, darfur wir E. L. freundlichen dangk sagen, entpfangen gelesenn”.

See below, Appendix, Text 3, fol. 1v. We reserve the analysis of both Apianus's theory and the Landgrave's criticism for future study.

“Wir befindenn gleichwoll, das E. L. Mathematici Tubingenses der obseruation mit großem vleiß vnnd Kunst nachgegangen, stimmen auch mit vnsern obseruationibus vff eyn geringes nahe vbereynn, wir befinden aber darnebenn auch das sie mangel ann Instrumenten habenn, vnnd das auß denn vrsachen, dieweill sie locum huius stellae verum nurt lineis visualibus ad stellas fixas deductis et non per instrumenta obseruirt. Es wird aber vieleicht E. L. Vniuersitet zu Thubingen so arm sein, das sie vleißige Instrumenta Mathematica nicht zeugen kan.” See below, Appendix, Text 3, fol. 1r.

See the letter to Tycho of 14 April 1586, with the contemptuous pronouncement against “astronomers under the roof, who are the majority” (“ein Mathematicus underm Dach, wie die meisten seind”), TBOO, vi, 49.

Cf. Progymnasmata, TBOO , iii, 63. 16–19. Cf. also the description by Maestlin in his treatise on the comet of 1577; see Maestlin M. , Obseruatio & demonstratio cometae aetherei, qui anno 1577. et 1578. constitutus in sphaera Veneris, apparuit (Tübingen, 1578), 21f. For a recent exposition of Maestlin's procedure see Schramm M. , “Zu den Beobachtungen von Mästlin”, in Zwischen Copernicus und Kepler (ref. 9), 64–71, pp. 68f.

Here it should be noted for the sake of precision that one of the two Copernican motives, the reference to the ‘motus commutationis’ of the superior planets according to De revolutionibus, V, 3, was in fact an addition in the printed edition, absent in the manuscript copy (see fol. 1v). The second motive, adducing the enormous empty space between the spheres of Saturn and the fixed stars, was already present in the manuscript copy (fol. 1v).

Suffice it here to quote only the letter to Duke Ludwig: “siehts vnns in vnserer einfaldt fur ein rechtt miraculum vnnd dero eines an, die vor dem jungsten tag sollen her gehen, dan dieweil zuuor gott der her die erste zukunfft seines sohns vnsers hern Christi durch einen stern hatt significiren vnd den weisen verkunden lassen, so hoffenn wir er werde durch dissen stern auch die letzte zukunfft des hern Christi verkundigen wollen”, Württenbergisches Hauptstaatsarchiv Stuttgart, A274 Bü 21. This letter is absent from Marburg.

This is the case in the addition (1r) relative to the changes of colour in the star: “mox in sanguineum, post in alium atque alium, demum circa finem Februarii in pristinum.”.

See fol. 1r: “Opinabantur aliqui oriturum inde Cometam, uerum accuratis postmodum habitis obseruationibus, edocti sumus, quod prodigiosa haec stella non modo non Meteoris, sed nec planetis, uerum octaui orbis seu firmamenti astris annumeranda sit”.

The digression covers TBOO, iii, 58. 31–59. 20.

“Alii singulis centennis vel quadringenis annis huiusmodi sydera redire, commenti sunt”, TBOO , iii, 59. 15–16. This interpretation sounds like that described (not fully seriously) by Wilhelm IV, as according to Fracastoro and Agrippa von Nettesheim, in his first letter to Caspar Peucer of 14 December 1572 (see Progymnasmata, TBOO, iii, 114. 19–28). This letter, however, is not present in the Archive in Stuttgart and does not seem to have been sent to Duke Ludwig by Wilhelm. The latter certainly sent the letter by Peucer of 1 January 1573 (in which Peucer rejected with scorn Fracastoro's and Agrippa's opinion) and his own letter to Peucer of 14 January 1573. See below ref. 99.

TBOO, iii, 60. 16–23, 27–38.

The addition corresponds to fol. 1v in the manuscript version. It is difficult, then, to explain how Methuen, op. cit. (ref. 32), 511, can affirm both that “Maestlin notes that the question of whether the observed object is a comet or a star has not been settled” and that “he [Maestlin] accepts that comets are not below the Moon, so that the supralunar sphere admits change naturally”.

Progymnasmata, TBOO, iii, 60. 34–36, quoted above, ref. 28.

“Fortuito enim illud emicuisse nemo sanus dixerit.”.

See ref. 14 above for Frischlin and ref. 52 for Wilhelm. Frischlin had welcomed the new star as a prelude to Christ's second coming with the following words: “Salue stella recens, venturi nuncia CHRISTI”, Consideratio nouae stellae (ref. 7), 9.

Cf. Kusukawa S. , The transformation of natural philosophy: The case of Philip Melanchthon (Cambridge, 1995), chap. 4 (“The providence of God”); cf. Methuen, Kepler's Tübingen (ref. 7).

“Optatae multo pacis sed sanguine partae, Nuncius est rebus hicce Cometa nouis”, Maestlin , Obseruatio & demonstratio cometae aetherei (ref. 50). This is obviously an allusion to the redemption of mankind by the blood of Christ, who is about to come again to bring peace.

We transcribe the anonymous copy in the Württenbergisches Hauptstaatsarchiv in Stuttgart (A 274, Bü 21). Another anonymous copy without significant variants is located in the Hessisches Staatsarchiv in Marburg (Bestand 4a f Württenberg 124). The first manuscript version is given in normal writing; the sections which were added later in the printed version are written in italics; the passages in the manuscript which were excluded in the printed version are given in bold.

1573: Anno superiori 1572. prima Mensis Nouembris hebdomada, noua quaedam Stella in sedili Cassiopeae. It is worth noting that in this manuscript report Maestlin says that the nova appeared in October. It is one of the few texts in which this date of appearance is given. Other texts are Camerarius's Observatio et descriptio novi sideris (ref. 2) and the anonymous French political pamphlet, La nouvelle estoile apparue sur tous les climats du monde: Et de ses effects (Paris, 1590).

Maestlin adds in the printed version the changes in colour observed in the nova after December 1572.

1573, in the margin: Iudicia quorundam de noua stella.

1573, in the margin: Arist. lib. 1. cap. 3. de coelo. Ptole. lib. 7. cap. 1. Almagesti.

1573, in the margin: Locus stellae nouae respectu centri mundi.

The printed edition substitutes this passage for the long development (pp. 27–28; TBOO, iii, 58. 31–59. 22) included in italics in the preceding lines. In it, Maestlin expounds with greater detail on the diversity of opinions on the nova.

1573, in the margin: Obseruatio motus stellae nouae.

1573, in the margin: Stella noua non habet diuersitatem aspectus, nec praeter diurnum.

This addition refers to presumed observations made by other authors in the time elapsed after December. It is probably an allusion to Ciprianus Leovitius, who in his report from 7 January 1573, De stella siue cometa, uiso mense Nouembri ac Decembri Anni Domini 1572. item mense Januario anni Domini 1573 (available in Württemberg from January 1573 and reproduced by Tycho in the Progymnasmata, TBOO, iii, 218f.), speaks of a sizeable displacement (3°) of the nova towards the constellation Cepheus.

1573, in the margin: Li. 4. ca. 1. lib. 5 ca. 11.

1573: ab apparenti non differre.

1573, in the margin: Ptole. lib. 4. cap. 1 Almagesti. Cap. lib. 4. cap. 17. reuol. orbium coelestium.

The addition aims to make more accurate and pointed the polemic against the supporters of the sublunary nature of the nova. 1573, in the margin: Purba. in Theor. ca. de diuersitate aspectus. Here is meant Georg Peurbach's Theoricae novae planetarum. See Aiton E. J. , “Peurbach's Theoricae novae planetarum: A translation with commentary”, Osiris, 2nd ser., iii (1987), 5–44, p. 30. For the other references, see Reinhold E. , Tabulae Prutenicae coelestium motuum (Tübingen, 1562), 136f. and Copernicus, De revolutionibus, IV, chaps. 17 and 22, fol. 119v and 123 (p. 123 of Maestlin's copy includes an annotation recording Reinhold's values).

1573, in the margin: Stella noua est in orbe stellato, seu extremo caelo.

1573, in the margin: Cop. lib. 1. cap. 10 Arist. lib.1. de coelo.

1573: Quoniam immensa est altitudo orbis stelliferi, quae quousque se extendat, non constat, ad quam, quae inter solem et terram est distantia concerni nequit (vt testatur Copernicus, Astronomorum post Ptolemaeum princeps, qui omnium orbium planetarum certas distantias a centro mundi demonstrans, in orbe stellato subsistit). In the margin added: Lib. 1. cap. 6. 10 & lib. 3. cap. 15. To the passages mentioned in the manuscript version (see above ref. 25) Maestlin now adds the tenth chapter of the first book. In his copy of the De revolutionibus he underlined, probably previously, the following lines: “tantam uero esse mundi magnitudinem, ut cum illa terrae a Sole distantia, ad quoslibet alios orbes errantium syderum magnitudinem habeat … satis evidentem, ad non errantium stellarum sphaeram collata, non quae appareat” (fol. 9), and “Quod autem nihil eorum apparet in fixis, immensam illarum arguit celsitudinem, quae faciat etiam annui motus orbem siue eius imaginem ab oculis euanescere” (fol. 10). On the annotations by Maestlin in his copy of De revolutionibus, see Westman , “Michael Mästlin's adoption of the Copernican theory” (ref. 23), 59–62, and Gingerich , An annotated census of Copernicus' De revolutionibus (ref. 20), 222–6.

Question mark omitted in both printed editions.

In the margin in both versions: Obseruatio Longitudinis et Latitudinis Stellae Nouae.

Sic. More correctly in the Marburg copy: Adscribenda sit.

1573 omits these two lines.

In the margin in both versions: Structura figurae demonstrationis.

Quinta Cassiopeia = δ Cass, Octava Cephei = ι Ceph, Duodecima Cassiopeia = β Cass, Vigessima Ursae Maioris = λ U Maj.

As indicated in the article, the geometrical demonstration presents many differences with respect to the printed version. The reference to Reinhold appears in the printed text in the margin: Reinholdus in tabulis direct. praecepto. 13. Here is meant E. Reinhold, Primus liber tabularum directionum (Tübingen, 1554), published after Reinhold's death in 1553.

Here is meant Theodosius, De Sphaericis libri tres, ed. by Voegelin J. (Vienna, 1529).

In the margin in the manuscript copy: Calculus.

The demonstration in the printed version introduces here the trigonometrical doctrine presented by Copernicus in De revolutionibus, I, 14 (“Spherical triangles”). In the margin, there is added: Coper. lib. 1. cap. 14. de angulorum magnitudine.

The sentence “Trianguli ergo BHA …” is mistakenly omitted in the Marburg copy.

Here is meant Regiomontanus J. , De triangulis omnimodis libri quinque (Nuremberg, 1533).

1573, in the margin: Locus stellae nouae respectu Zodiaci.

Manuscript, in the margin: Locus Stellae nouae 6° 35′ . Latitudo Borealis 54° 0′.

This reference to Copernicus has moved in the printed version to the margin: Cop. lib. 2. cap. 4 Positus stellae nouae respectu aequinoctialis.

Hessisches Staatsarchiv Marburg, Bestand 4 f Württenberg 124. In Stuttgart (Württenbergisches Hauptstaatsarchiv, Bestand A274 Bü 21) is preserved only a draft of this letter. As the content makes clear, it is the first communication on the nova between Württemberg and Cassel. The reports by mathematicians in Tübingen sent to Cassel are those by Philippus Apianus (ordinary professor of mathematics and astronomy at the University from 1570 until 1584) from 26 December and an anonymous report entitled Noua stella, whose author was Michael Maestlin. Both reports are preserved together with this letter in the State Archives in Marburg and Stuttgart.

Wilhelm IV had married Sabine of Württemberg (1549–87), daughter of Christoph of Württemberg and sister of Ludwig. Wilhelm was therefore brother-in-law (the specific meaning of the German ‘Schwager’) to Duke Ludwig of Württemberg.

Hauptstaatsarchiv Stuttgart (Bestand A 274 Bü 21). An almost identical copy exists in Marburg, Hessisches Statatsarchiv (Bestand 4 f Württenberg 124).

With this letter were included the Latin letter of 1 January 1573 written by Peucer to the Landgrave (reproduced by Tycho , TBOO , iii, 120–3) and Wilhelm's answer in German of 14 January 1573 (reproduced by Tycho in Latin translation, in TBOO, iii, 127–9). These letters are registered as annexed by the Landgrave and indeed are present in the dossier in Stuttgart. Wilhelm did not send the first letter by Peucer of 9 December; this letter was received later, from Ludwig von Hessen, Wilhelm's brother, who sent it to Duke Ludwig of Württemberg on 14 February.

Wilhelm expresses his willingness to start an open discussion of the nova in several places in Germany.

As argued above, Wilhelm alludes here to Maestlin's handwritten report.

Mathematica is absent in the copy in Marburg.

Cf. Apianus P. , Ein kurtzer bericht der Obseruation vnnd vrtels des Jünger erschinnen Cometen … dises XXXII. Jars (Ingolstadt, 1532). Concerning this ‘optical theory’ of comets and cometary tails, see Barker P. , “The optical theory of comets from Apian to Kepler”, Physis, xxx (1993), 1–25.

This refers to the comet that appeared in 1556.