Meet NGC 3324 and IC2599 The Gabriela Mistral Nebula - VisibleDark

Zoom into Star-Forming Region NGC 3324 in the Carina Nebula - NASA Science

Use the result of Problem 6.3 for NGC 1399's central surface brightness, and assume that all this light comes from the core of radius rc=2^'' or 650 pc, to find the core luminosity density. Show that the luminosity density at the center of the Virgo cluster is 2500 times greater than average for the Universe as a whole (see Equation 1.25), but the core of NGC 1399 is 10^7 times denser yet. Stars are packed far more tightly into galaxies than galaxies are packed into clusters. | Numerade

The core radius rc of NGC 1399 is ∼5^'' or 400 pc. Use Equation 3.46 to combine the measured dispersion σr from Figure 6.12 with the result of Problem 6.3, to show that the mass-to-light ratio in the central parts is ℳ / LV ∼7. This is only slightly larger than that in the Milky Way's globular clusters (Section 3.1), suggesting that the core of this galaxy contains little dark matter. | Numerade

NGC 3314

Hubble Images a Classic Spiral  - NASA Science