Science. 1987 Mar 13;235(4794):1367-70. doi: 10.1126/science.235.4794.1367.
Combined optical and radio images of galaxies can provide new insights into the sizes, masses, and possible evolution of these objects. Deep optical and neutral hydrogen images of Markarian 348, a type 2 Seyfert galaxy, show that it is a gigantic spiral (perhaps the largest known non-cluster galaxy). Measurements of the neutral hydrogen velocity field and spiral structure, and detection of an optical "tidal plume," all provide evidence that it has been subject to tidal disruption. The measured velocities yield a mass-to-light ratio for this object (within a radius of 130 kiloparsecs from its nucleus) that is similar to the ratio found for the inner regions of most galaxies of similar type. This is one of the few cases where detailed velocity measurements have demonstrated that a galaxy with an active nucleus has been subject to extensive tidal perturbation.
星系的光学和射电图像结合可以为这些物体的大小、质量和可能的演化提供新的见解。对马克里安 348（一种 2 型塞弗特星系）的深光学和中性氢图像的研究表明，它是一个巨大的螺旋星系（也许是已知的最大非星团星系）。中性氢速度场和螺旋结构的测量，以及光学“潮汐羽流”的探测，都提供了它曾受到潮汐破坏的证据。测量得到的速度给出了该物体的质量-光度比（在离其核心 130 千秒差距的范围内），与大多数类似类型星系的内区的比值相似。这是少数几个详细的速度测量表明具有活跃核心的星系已经受到广泛的潮汐扰动的情况之一。
