James Webb peers into nearby dwarf galaxy, sheds light on planetary evolution

Before they are formed, planets are merely dust swirling throughout the cosmos. Over many millennia, these microscopic grains of sand, or soot-like dust, stick together to form pebbles—those pebbles then conglomerate to form rocky planetesimals, which eventually collide to form planetary cores.

The dust starting the entire process is typically made from elements such as silicon, magnesium, aluminum, and iron. However, supplies of these elements are relatively scarce in the SMC.

Planetary formation may have occurred during the 'cosmic noon'

Now, using new infrared images from James Webb, a team of scientists detected signs of this dust in a region of the SMC called NGC 346. Webb is able to detect thermal radiation emitted from warm dust, meaning the researchers were able to pinpoint dust that was orbiting close to young stars. This suggests that planets should be able to form in the region as the stars mature.

The scientists determined that the abundance of rock-forming elements in the SMC is similar to that of galaxies from roughly 11 to 12 billion years ago. This also led the authors to infer that planetary formation may have been possible during the early period of the universe known as the "cosmic noon", roughly 11 billion years ago.

The new findings are another example of Webb's impressive ability to peer into regions of space where stars and planets are in their very earliest evolutionary stage. For example, one of its very earliest images peered through the Carina Nebula's dust clouds at the stellar nurseries beneath.