Webb captures commotion from nebula's stellar jets

The James Webb Space Telescope has revealed previously hidden stars in the NGC 7129 stellar nursery, located 3,300 light-years away from Earth. The infrared light captured by the telescope penetrates the dense matter, which often obscures other types of light. This region is a vibrant mix of stars at various stages of their life cycles, offering scientists a chance to study how stars influence their surroundings.

The largest and most mature star in this cluster, LkH(alpha) 234, is the central star responsible for the prominent diffraction pattern in the image. With a mass approximately five to eight times that of our sun, this star has mostly completed its mass accumulation and is now contracting under gravity's pull, causing its temperature to rise. Eventually, it will begin fusing hydrogen like our sun.

One of the most striking features in the image is a large cavity to the left of the central star. This cavity, spanning about 3.5 light-years, is the result of outflows from the star's earlier life stage carving into the dense molecular cloud of hydrogen. The star's light and outflows heat the gas, causing it to glow. Much of the hydrogen gas is blown away, but a significant portion is compressed, creating conditions for the birth of new stars.

Embedded within this cavity are several pre-main-sequence stars, which are generating stellar winds. These winds interact with the surrounding gas, forming curved bow shocks that appear as compressed gas near the stars. The central star and the embedded stars create a hot environment that pushes against the colder, denser molecular gas, forming a boundary known as a photodissociation region.

In this region, hydrogen molecules break down into atoms, influencing the region's heating, cooling, and chemistry. This interaction helps gradually erode the molecular clouds over millions of years.

On the right side of the central star, a different yet chaotic scene unfolds. This region is populated by much younger protostars, which are in an earlier stage than pre-main-sequence stars. These protostars have not yet completed mass accumulation and are still surrounded by dense molecular clouds. As they gather more mass, they eject superheated outflows that interact with the surrounding dense material, creating shocks that give the region its textured appearance.

The red glow in this area is also due to the interaction between the protostars and their surroundings. Multiple outflows from different stars overlap from our point of view, contributing to the region's chaotic appearance.