Why are the spiral arms bright with newborn, massive stars?
Answer
They are active stellar nurseries where material piles up due to density waves.
The spiral arms are bright because they are the active stellar nurseries where density waves passing through the disk cause gas and dust material to pile up, leading to the recent formation of massive, bright stars.
Related Questions
What are the primary gaseous components of the Interstellar Medium in spiral galaxies?Up to what diameter do cosmic dust particles typically range in size?Which types of refractory materials constitute the composition of cosmic dust?In which part of a spiral galaxy is the gas and dust overwhelmingly concentrated?What characterizes the stellar population and material reserves in the central bulge of a spiral galaxy?What term is used to describe the effect where dust absorbs and scatters light from stars located behind it?At which primary spectrum does dust reradiate the energy it absorbs from visible light?Why are the spiral arms bright with newborn, massive stars?What specific materials do massive stars enrich the ISM with when they die in supernova explosions?What role do dust lanes play when observed using visible light telescopes?