Lenticular galaxy (designated S0) is recognized as being distinct in appearance from both the spirals and ellipticals, though this type shares some characteristics of each. The S0 galaxies have smooth light distributions, like the ellipticals. On the other hand, they are definitely flat systems that are more like spirals containing both a halo population of stars (S0 galaxies show nuclear bulges) as well as a disk population of stars.
Their rotational characteristics are like those of the faster rotating spirals and the surface brightness fades away toward the edge in the same manner as the spirals. As for other properties, these galaxies have intermediate sizes, masses, and luminosities; that is, no truly giant or truly dwarf S0 types are found .
Their rotational characteristics are like those of the faster rotating spirals and the surface brightness fades away toward the edge in the same manner as the spirals. As for other properties, these galaxies have intermediate sizes, masses, and luminosities; that is, no truly giant or truly dwarf S0 types are found .
In Hubble's interpretation, these galaxies are composed only of stars, with no interstellar gas, and consequently no star formation‐defining spiral arm regions. The S0 galaxy (and its barred counterpart, the SB0) were considered to be an “intermediate” or “transition” form of galaxy between the ellipticals and spirals
In the modern understanding of galaxies, this interpretation has been called into question, because it is now known that there exist apparently perfectly normal S0 galaxies that have significant fractions of their mass in the form of interstellar gas.
In the modern understanding of galaxies, this interpretation has been called into question, because it is now known that there exist apparently perfectly normal S0 galaxies that have significant fractions of their mass in the form of interstellar gas.