Observations and drawings of nebulae

manuscript, lithographs and drawings, Arcetri 1875-1880

plate VIII. Neb. Gen. Cat. 138 [NGC253]

plate XIX Neb. Gen. Cat. 2372, 2377 e 2378 [Leo triplet: M65, M66 e NGC3628]

litographs, 230 x 300 mm

INAF-Arcetri Astrophysical Observatory, Historical Archives, Tempel fond

The two lithographs were realized from drawings made by Wilhelm Tempel using the Amici I equatorial telescope of the Arcetri Observatory. They are part of a collection of 22 plates with which Tempel won in 1880 the H.M. Umberto I Prize for Astronomy of the Royal Academy of the Lincei. The publication of this work was planned but never executed because of the difficulties met in reproducing the fine nuances of the drawings. Only the introductory text was published in 1885 in an expanded form under the title Über Nebelflecken. The objects represented in the drawings shown here are galaxies, large systems of stars
which appear to us as a faint nebulosity due to their distance. The first spectroscopic observations of nebulae, made by William Huggins, showed that some of them had spectra similar to the stellar ones; thus, they are made of stars and are called galaxies, to distinguish them from true nebulae (see Fi. 11).

Bibl.: TEMPEL 1885, HUGGINS 1864, CHIMIRRI ET AL. 2009.