[ETHEREAL MUSIC] Within galaxies, the bright clouds are the places where gas and dust collapse to form stars. In infrared light, NASA's James Webb Space Telescope sees into these nebulae with unprecedented detail. Some galaxies have regions with furious levels of star formation. 

Astronomers call them starburst galaxies. The starburst activity is perhaps too fast, as it will relatively quickly deplete the available gas and dust. Webb observations help explain why and how so many galaxies undergo these short, vibrant periods of star formation. 

Messier 82, known as the Cigar Galaxy, doesn't look like a starburst galaxy, until the light of hot hydrogen reveals a huge outflow of gas and dust, called the galactic wind. Webb's infrared view sees the full extent of the galactic wind and pierces through to its source, a region of intense starburst activity in the galaxy's core. 

We can explore M82's structure using a 3D visualization. The cigar is actually a disk of stars seen mostly edge-on. Within the disk, Webb detects faint stellar spiral arms, confirming that M82 is a spiral galaxy. 

A central ring of intense star formation contains hundreds of massive star clusters. The combined power of supernova explosions within these star clusters creates the galactic wind. What can trigger such a spectacular outburst? 

The cause appears to be a recent gravitational encounter between M82 and the more massive spiral galaxy, M81. Many other galaxy interactions and collisions produce vibrant star formation. These gravitational encounters are a known trigger for starburst activity. Webb observations provide precise characteristics of this short-lived but common phase in the development of galaxies. 

They also provide insight into the distant universe, where Webb has uncovered a collection of starburst galaxies that existed in the first billion years. Although images of these important starburst galaxies are small and fuzzy, their properties can be inferred from high-resolution observations of nearby starburst galaxies. Webb's keen eye is providing novel insights into local starburst galaxies, as well as discovering and interpreting these dazzling environments in distant galaxies. 

[ETHEREAL MUSIC]