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We present the results of our study of the peculiar motions for 41 galaxy clusters and groups in the regions of the Hercules and Leo superclusters (0.027 < z < 0.045). For this purpose, based on SDSS (Data Release 8) data, we compiled a sample of early-type galaxies in the investigated clusters and groups, constructed their fundamental planes (FPs), and determined independent distances and peculiar velocities. The Hubble law between the radial velocities galaxy clusters and the distances derived from the FPs holds for the rich Hercules supercluster as a whole. At the same time, however, significant peculiar motions along the line of sight with rms deviations of 736 ± 50 and 584 ± 50 km s−1 are observed within this supercluster and in its immediate neighborhood. In the poor Leo supercluster, the rms deviation is also large, 625 ± 70 km s−1. Its Hubble diagram exhibits the approach of galaxy clusters and groups along the line of sight relative to the most massive cluster A1185. In the immediate neighborhood of the Leo supercluster (virtually in its field), the rms deviation of the peculiar velocities is minimal, 287 ± 60 km s−1.

We investigated the properties of galaxy clusters in the region of the Hercules supercluster using observational data from the SDSS and 2MASS catalogs and the NED. We have selected 13 galaxy clusters with a total dynamical mass of 4.82 × 1015 M ⊙ in a 100 × 45 Mpc supercluster region in the plane of the sky (0.030 < z < 0.041). In addition, our sample includes eight clusters from the immediate neighborhoods of the superclusters and ten field clusters at the same z. The derived properties of the rich Hercules supercluster are shown in comparison with the data for the poor Leo supercluster. The main parameters of the virialized galaxy cluster regions in the near infrared (K s ) for the Hercules supercluster differ from those for the Leo supercluster: the number of galaxies and the total luminosity (to a limiting magnitude of −21 · 5) increase with cluster mass (L K,200 ∝ M 200 0.91±0.07 and N 200 ∝ M 200 0.94±0.07 ), but the dependences are steeper by 0.28 and 0.22. In the virialized cluster regions, the fraction of early-type galaxies selected by the bulge contribution, concentration index, and u t= r color is, on average, 66% (60% in Leo, 70% in the field) among the galaxies brighter than −23 · 3 and 54% (51% in Leo, 61% in the field) among the galaxies brighter than −22 · 3. The fraction of early-type galaxies in the superclusters does not change with galaxy cluster mass and luminosity. The composite luminosity function of the rich Hercules supercluster is described by a Schechter function and does not differ from the luminosity function of the poor Leo supercluster for the luminosity interval [−26 m , −21 · 5] but differs from the field luminosity function at the same z determined from ten galaxy clusters.

We analyze the properties of galaxy clusters in the region of the Leo supercluster using observational data from the SDSS and 2MASS catalogs. We have selected 14 galaxy clusters with a total dynamical mass of 1.77 × 1015 M ⊙ in the supercluster region 130 by 60 Mpc in the plane of the sky (z ≃ 0.037). The composite luminosity function of the supercluster is described by a Schechter function with parameters that, within the error limits, correspond to field galaxies and does not differ from the luminosity function of the richer Ursa Major (UMa) supercluster for the same luminosity range (the bright end). The luminosity functions of early-type and late-type galaxies in Leo at the faint end are characterized by a sharp decrease (α = −0.60±0.08) and a steep increase (α = −1.44± 0.10) in the number of galaxies, respectively. In the virialized cluster regions, the fraction of early-type galaxies selected by the u-r color, bulge contribution, and concentration index among the galaxies brighter than M * + 1 is, on average, 62%. This fraction is smaller than that in the UMa supercluster at a 2–3σ level. The near-infrared luminosities of galaxy clusters down to a fixed absolute magnitude correlate with their masses almost in the same way as for other samples of galaxy clusters (L 200,K ∝ M 200 0.63±0.11 )).

The data on the peculiar velocities of 1493 RFGC flat spiral galaxies processed using the POTENT method allowed the density distribution of matter, including dark matter, on 75-Mpc scales to be reconstructed. Well-known attractors (the Great Attractor, the Perseus—Pisces and Coma superclusters) and voids are separated from the distribution. In general, the density distribution is close to that of IRAS galaxies, suggesting that the luminous-to-dark matter density ratio is constant. The masses of the main attractors were estimated.

The apparatus of a correlation gamma function is used to analyze the spatial clustering of galaxies in the Local Supercluster. In particular, we analyzed a sample corrected for the peculiar velocities of the Local Supercluster galaxies by using our original technique for separating groups of galaxies. It turned out that the peculiar velocities did not significantly distort the gamma function even for relatively small sample sizes. The distribution of the galaxies obeys a power-law decrease in density with an index of 0.6–0.7. We found evidence for a luminosity dependence of the degree of galaxy clustering within the volume under study.

Kormendy’s relation (μe-logR e) is used to investigate the structure of the compact Ursa Major supercluster of galaxies (11h30m+55°, cz=18 000 km s−1); this relation allows the distances of early-type galaxies to be estimated. The relative distances of 13 clusters in the supercluster and their peculiar velocities are determined with a mean statistical accuracy of 6%. In general, the supercluster obeys the Hubble relation between radial velocity and distance. However, there is reason to suggest that the supercluster consists of two subsystems with mean radial velocities of 16 200 and 19 700 km s−1. For a velocity dispersion in the subsystems of ∼1100 km s−1, the fact that each of them is gravitationally bound is not ruled out.

Catalogs of bright galaxies in the central regions of 11 clusters in the Ursa Major supercluster are presented. Absolute and relative coordinates and total B and R magnitudes are given for each galaxy. Plates taken with the 2-m Tautenburg Observatory telescope and CCD images obtained with the 6-m and 1-m SAO telescopes are used. The luminosity functions (LFs) for galaxies in the cluster nuclei (3 Mpc×3 Mpc) and the composite LF for the supercluster are constructed. The composite LF is well fitted by a Schechter function with $$M_B^ * = - 20\mathop .\limits^m 91$$ , α=−1.02 and with $$M_R^ * = - 22\mathop .\limits^m 39$$ , α=−1.06. A comparison with the LFs of field galaxies and of various samples of clusters and superclusters shows that the Ursa Major supercluster have LF parameters characteristic of the field and, thus, differ from those of the Corona Borealis supercluster, which is apparently at a later stage of dynamical evolution.