mars in the schiaparelli-lowell’s correspondencesait.oat.ts.astro.it/msais/6/pdf/12.pdfmanara:...

Mem. S.A.It. Suppl. Vol. 6, 12c© SAIt 2005

Memorie della

Supplementi

Mars in the Schiaparelli-Lowell’s correspondence

A. Manara1

Istituto Nazionale di Astrofisica – Osservatorio Astronomico di Brera, Via Brera, 28 I-20121Milano, Italy e-mail: manara@brera.mi.astro.it

Abstract. In this article the correspondence between the famous italian astronomerGiovanni Schiaparelli and Percival Lowell, founder of the Flagstaff Observatory in Arizonais briefly presented.

Key words. Mars; Schiaparelli

1. Introduction

Giovanni Schiaparelli (1835-1910) andPercival Lowell (1855-1916) studied in detailthe planet Mars, therefore the correspondencefocuses on this topic. Thirtyfive unpublishedletters (34 in French, one in English) writtenfrom 1896 until Schiaparelli’s death arepresented. The original letters from Lowelland some drafts by Schiaparelli are preservedin the archives of the Brera AstronomicalObservatory; Flagstaff Observatory has kindlyprovided us with some of the original lettersby Schiaparelli.

2. Subjects of the correspondence

The correspondence, nearly entirely on Mars afew cases except on Mercury and Venus, showsa remarkable friendship and the thrust of therelationship is that of a respectful successor tohis very much admired guru. The epistolary ex-change on Mars begins in 1896. In a series ofletters in the spring of 1903, Lowell tells hismentor about discoveries that agree with priordeterminations by Schiaparelli; he replies that

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some of the changes on Mars appear as repet-itive pattern, and goes on to say that “...unelongue maladie m’a rendu tellement faible...”and “...vers 1892 mon oeil commenca a sedeformer peu a peu, et mes observations a cettedate ne sont plus comparables aux observationsanterieures...en 1899 j’ai du cesser non seule-ment les observations de Mars, mais toute ob-servation astronomique...Maintenant mon oeilgauche, qui jadis a ete si parfait, est presquecompletement aveugle”. For Lowell is alwayspleasant to observe again what Schiaparelli hadalready seen; the structures on Mars’ surfaceare affectionately called “Votre Thot et LacusMoeris...” Lowell is very sad for the eyes ofthe colleague, eyes that “...ont tant vus pour lascience dans leurs jours heureux”. Schiaparellideclares repeatedly his esteem for the studiesof Lowell on Mars; for instance he thinks thathis Memoria “The cartouches of the canals ofMars” is a new method to consider the Marsphenomena. Lowell defined “cartouche of acanal of Mars” its percentage of visibility ina certain date (the percentage of visibility wasdetermined from numerous drawings availableat that time for all the periods of the year).For Lowell it is always important to inform

Manara: Mars & Schiaparelli 13

Fig. 1. Syrtis Major Region by Lampland’s photograph and Lowell’s drawing.

quickly Schiaparelli on the “news” of his ob-servations: “...vous m’ecriviez une fois qu’al’avenir il vous fallait observer per les yeux des

autres. En souvenir de cette triste declarationje vous envoie les primeurs de mes observa-tions de cette opposition de 1905”. In the let-

14 Manara: Mars & Schiaparelli

Fig. 2. Postcard of Flagstaff after a snow storm.

Manara: Mars & Schiaparelli 15

Fig. 3. Moon and Mars spectrograms taken by V.M. Slipher.

ter of August, 14th, 1905, Lowell sends five ta-bles that report the results of observations offive regions of the Mars’ surface, obtained vi-sually from himself and photographically fromLampland (Fig.1 shows one of these tables).

In June of 1906, Lowell tells his men-tor: “Je viens de mettre main a la conclusiond’un nouvel livre sur la planete Mars et jevoudrai demontrer mon estime en le dedianta vous a qui on doit les magnifiques primeursde ces recherches”. Schiaparelli agreed to ac-cept the tribute. Interestingly the letter ofSchiaparelli of March, 1907, about Mars’observations performed by Babylonians con-cludes: “...Cette planete (Mars) est vraimentprecieuse. Elle a sortie les premiers essaisde Babyloniens, avec son moyen Kepler adecouvert ses deux premiers lois: maintenantelle va devoiler le mystere de la vie sur unautre monde. C’est le Mars terrestre, c’est adire la guerre, qu’il faut abolir.” In Fig.2 we cansee the postcard sent from Lowell to the ital-ian astronomer in the spring of 1907 showingFlagstaff’s Observatory after a snow storm. Onmarch, 1909, Lowell replies to Schiaparelli,

who suggested to show his photograph platesto Antoniadi before the issue:“Cher MaitreMartien et honore Collegue,...malgre ce quevous m’ecrivez de vos pauvres yeux, vous pou-vez encore beaucoup voir que M. Antoniadi outout autre qui n’a pas bien etudie la planete.”“... Faites cet honneur, je vous prie, a laScience”. In the same letter is enclosed aspectrum (Fig.3), as a present for Schiaparellibirthday (14 March), taken by V. M. Slipher,showing the “a” band stronger in the Martianthan in the Lunar spectrum, thus testifyingto water-vapor in the Martian atmosphere.Schiaparelli ’s last letter of 23th April, 1910,treats several subjects. First, he emphasizesthat, a part from certainty given by mathe-matical and experimental proof, progress inknowledge may come also from possibility andprobability, like “...l’oeuvre de Copernic, ellememe, n’etait pas elle fondee d’abord sur desimples probabilites? La certitude n’est arriveeque 150 ans plus tard”. Afterwards the dis-quisition comes back on Mars; Schiaparelliwaits for Lowell’s photographies and there-fore hopes to solve shortly the problems

16 Manara: Mars & Schiaparelli

connected to the Mars’s structures. At lastSchiaparelli promises to send to Lowell hislast issue, the VIII Volume of Mars’ Memorie:“Hic cestus, artemque repone” and closes:“Malgre cela m’interesserai toujours vive-ment aux grand progres que l’Astronomie faitchaque jour, et dont quelques unes marquerontune belle epoque dans l’histoire de cette sci-ence”. Lowell’s final letter of June, 14th, 1910,only three weeks before Schiaparelli’s death,continued to discuss the canals but concludes“...From my heart, your devoted, Percival

Lowell”; probably this letter was never readfrom the receiver because he suffered throm-bosis on June, 22th. Schiaparelli died on July,4th, 1910.

Acknowledgements. I am grateful to A. Wolter forsome helpful comments

References

Nuncius, 2004, Annali di Storia della Scienza,Olschki ed., Firenze, Anno XIX, fasc. 1.