1821, at Nieder-Kunersdorf, near Löbau, in the kingdom of Saxony.

His parents were people in poor circumstances, and so he received but

a scanty education, which in after years he lost no opportunity of

improving. When about twenty years of age he went to Copenhagen, where

he worked for about three years as a lithographer, and where his

lively manners and his taste for music and art acquired for him many

friends, some of whom he never lost sight of. After leaving Copenhagen

he went for some time to Christiania, and his roving spirit then

brought him to Italy, where he settled at Venice and exercised his art

for many years. Having become interested in astronomy he purchased a

4-inch refractor by Steinheil, with which he began exploring the

heavens. It was a great encouragement to him to persevere in this

occupation (for which he had obtained leave to use the balcony of a

an enthusiastic observer until his last illness. He was the first to

around Merope in the Pleiades, the announcement of which,

though confirmed by various observers with small instruments, was

received with much hesitation, as the object was less readily seen

with a larger aperture and higher power.

In March 1860 Tempel went to Marseilles, where he obtained employment

at the Observatory,

which was then under the direction of Valz. He

and also turned his attention to the minor planets, of which he in the

years 1861 to 1868 discovered five. He remained attached to the

Observatory till towards the end of 1861, when he settled in the Rue

Pythagore, Marseilles, and resumed his work as a lithographer. But

Tempel continued to show himself an indefatigable observer, and as he

had only his 4-inch refractor he was naturally induced to remain

faithful to the field of work in which he had first been successful

– that of comet-seeking. Among the eight comets which he found

while at Marseilles, [1] the first one of

1866 attracted great attention from its connection with the November

meteors, while the second one of 1867 was found to belong to the

interesting class of periodic comets of short period. It was observed

again in 1873 and 1879, but in 1885 was too distant and too faint to

Tempel, was in 1880 found to be periodic; it is known as Tempel’s

third periodic comet, and passed the perihelion in May 1886, when it

was too unfavourably situated to be observed.

In January 1871 Tempel was as a German expelled from France by the

Provisional Government. He went to Milan, where Professor Schiaparelli

was glad to accept his services as an assistant at the Brera

Observatory. There he continued observing comets, and discovered three

new ones, [2] among which his second

short period – only a little over five years. It was observed

again in 1878, but was unfavourably placed with regard to the earth

both in 1883 and 1889. Tempel’s observations made at Milan, chiefly of

comets, were published in the Milan ephemeris for 1872 and in

Observatory; in the latter there is a fine lithographed plate of the

Pleiades with the Merope nebula, which he later improved by the

addition of many minute stars, after which he republished it in the

L. O.].

Towards the end of 1874 Tempel left Milan to accept the post of

Assistant in charge of the

Arcetri Observatory,

which is connected

with the Reale Instituto di studi superiori of Florence. Having

now for the first time the use of larger instruments, he thenceforth

devoted himself to observations of a more systematic character, and

I., which was detected both by him and by Winnecke within a few

minutes), while he found four which had been detected somewhat earlier

by other observers, [3] and one cometary

again.

The Observatory at Arcetri had been erected in the years

1869–1872 from the designs of Donati, but when this energetic

astronomer died in September, 1873, the buildings, though externally

finished, were not complete, and the mounting of the largest

instrument – a refractor by Amici, of 11 inches aperture –

was far from finished, so that there was neither clockwork nor

graduations on the circles. The building seems also to have been badly

constructed, as the walls of the meridian-room had to be stengthened

in 1875 to prevent them from giving away. Nobody appears to have taken

the slightest interest in the observatory after Donati’s death, and

for fourteen years Tempel had to struggle on, subsisting on a scanty

salary, and endeavouring to do good work with a half-finished

instrument. The years which Tempel had spent in comet-seeking had

caused him to take a great interest in nebulae, and, notwithstanding

all the obstacles with which he had to contend at Arcetri, he resolved

to apply himself to observations of these objects. He had at his

disposal two instruments with object-glasses by Amici, both of which

were optically suitable for observing nebulae. One was a refractor of

9.4 inches aperture and 10.5 feet focal length, roughly mounted on a

portable stand, but it does not appear to have been much used, as a

slight wind was sufficient to set it in motion on the sloping terrace,

which was the only place where it could be used. The other refractor

has 11 inches aperture and 17.5 feet focal length, and is equatorially

mounted under the central dome; but mounting and dome have been so

badly designed that objects in altitudes less than 20° cannot be

observed. Undaunted by these difficulties, Tempel collected a

considerable number of observations of nebulae. Many of his results

have appeared in a series of notes in the Astronomische

Nachrichten (vols. 90–113), from which it may be seen that a

great number of objects not observed elsewhere since Sir W. Herschel’s

time have been examined and their places corrected, and many new

nebulae found and micrometrically observed. But, above all, Tempel

devoted his attention to the making of accurate drawings of the more

interesting nebulae, a pursuit for which his artistic skill and

experience made him particularly fitted; while he had also the

advantage of a very pure sky and an instrument of sufficient aperture

and excellent defining power. A photographic reproduction of a drawing

of the nebula of Orion will be found in a short memoir on

nebulae printed in 1885 in the Abhandlungen der K. Böhmischen

Gesellschaft der Wissenschaften (revieved in the

the same memoir, comprising 186 nebulae, or groups of nebulae. It

would appear that steps were taken some years ago to have these

drawings published, as Tempel in 1886 sent the writer of these lines a

lithographed plate, which he described as a failure, adding: “It

belongs to my Roman work on nebulae (22 plates), which unfortunately

will probably never be published, as we hitherto have not found an

artist capable of copying my nebulae.” It is very much to be

hoped that this work may be published, together with Tempel’s numerous

notes and measures (with an annular micrometer) of neighbouring stars

and companion nebulae. In the beginning of 1887, when he found himself

unable to observe, Tempel began to arrange and put in order his

scattered notes and sketches, many of which has as yet only been

jotted down on various maps, and intended to enter them all in a copy

of Herschel’s General Catalogue, interleaved with two white

leaves betwen each two pages, but we are not aware whether he

succeeded in completing this task. We trust, however, that his Italian

confrères will not allow his work to be buried in oblivion, but

that they will interest themselves in having it published in the same

systematic and complete manner in which the obsevations of Dembowski

were given to the world some years ago.

Tempel’s mind, which always has been somewhat inclined to melancholy,

had in Italy found peace by embracing the Roman Catholic faith. About

the end of 1886 he was attacked by a liver complaint, and some months

16, 1889, when

death relieved him from his sufferings. His mind remained clear to the

last. He was buried near the tomb of Donati, his predecessor in charge

of the Arcetri Observatory.

In addition to various prizes from the Vienna Academy for his

discoveries of comets, Tempel, in 1879, received the prize which every

six years is awarded by the Accademia dei Lincei for some astronomical

10,

1881.

Footnotes

(Click on a footnote number to return to the

main text or here to get to the top.)

[1] 

[2] 

[3] 

[4] 

A drawing of the Orion nebula, in 1861, drawn and lithographed by

J.L.E.D.

Leos Ondra

([email protected])

Hartmut Frommert

([email protected])

Christine Kronberg

([email protected])

Last Modification: 10 Feb 1998, 21:30 MET