2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/8959We present results of Fabry-Perot and long-slit spectroscopy of the peculiar galaxy Arp 10. The ionized gas velocity field shows evidence for significant radial motions in both outer and inner galactic rings. Long-slit spectroscopy reveals gradients of age and metallicity of stellar population in agreement with the propagating nature of star formation in the galaxy. We present strong evidence that a small ``knot'' at 5 arcsec from the center of Arp 10 is its dwarf elliptic satellite, the most probable ``intruder'' responsible for triggering the expanding rings in Arp 10.6 pages, 5 figures, poster contribution on American Astronomical Society Meeting 205, #26.05Astrophysicstext