Next Contents Previous

D. WILD's Triple Galaxy

This system was found by my assistant Mr. P. WILD (31) with the 18-inch Schmidt telescope on Palomar Mountain and was subsequently investigated with the 48-inch Schmidt and the 100-inch and 200-inch reflectors. A photograph of these remarkable three nebulae which bear no NGC or IC designation is shown on Plate V.

Plate
 V

Plate V. Photograph of WILD's triple system obtained with the 200-inch telescope on Eastman 103a-0. Scale = 1' arc.

The two southern preceding objects are the most remarkably similar spirals with a very symmetrically located intergalactic filament and equally symmetrical second spiral arms or countertides. The third most northern component is a barred spiral which is connected with the central spiral by a luminous intergalactic bridge describing a loop on its way from one nebula to the other. The apparent magnitudes given in the following were determined by WILD from films obtained with the 18-inch Schmidt telescope by the "Schraffiermethode". Dr. HUMASON again was kind enough to analyse the spectra of the three galaxies. The data obtained so far are as follows.

First Spiral. R.A. 11h 44m 02s and Decl. -3° 34' 54"; apparent photographic magnitude mp = +14.5. Symbolic apparent velocity of recession Vs = 5108 km./sec.

Second Spiral. R.A. 11h 44m 12s and Decl. -3°34'12"; mp = +14.1; Vs = 4973 km./sec. and 5180 km./sec. as determined for two different gaseous emission patches.

Barred Spiral. R.A. 11h 44m 16s and Decl. -3° 32' 42"; mp = +15.0; Vs = 5224 km./sec.

Generally it may be stated that all three galaxies show emission lines with lambda3727 the strongest and considerably weaker Hbeta and Hdelta. Hgamma is visible only in the spectrum of the central brihtest nebula. The continuous spectra are strong in all cases and extending well into the violet. There is no trace of any absorption lines except in the faintest member, the barred spiral, in which the H and K absorption lines show up very weakly. The differences in the velocities of various emission patches within the same nebula indicate fairly violent internal motions. Using HUBBLE'S old scale based on the redshifts the distance of the group is about 9.6 megaparsecs and the whole formation in the plane normal to the line of sight is 50000 light years long. At the distance indicated the absolute photographic magnitudes of the three galaxies are -15.8, -15.4 and -15.0.

Next Contents Previous