Webb Studies Cranium Nebula

Nebula PMR 1 is a cloud of gas and dust that bears an uncanny resemblance to a brain in a transparent skull, inspiring its nickname, the “Exposed Cranium” nebula. Webb captured its unusual features in both near- and mid-infrared light. The nebula was first revealed in infrared light by a predecessor to Webb, NASA’s now-retired Spitzer Space Telescope, more than a decade ago. Webb’s advanced instruments show detail that enhances the nebula’s brain-like appearance. This image, released on Feb. 25, 2026, is in near-infrared light.

The nebula appears to have distinct regions that capture different phases of its evolution — an outer shell of gas that was blown off first and consists mostly of hydrogen, and an inner cloud with more structure that contains a mix of different gases. Both Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) show a distinctive dark lane running vertically through the middle of the nebula that defines its brain-like look of left and right hemispheres. Webb’s resolution shows that this lane could be related to an outburst or outflow from the central star, which typically occurs as twin jets burst out in opposite directions. 

Read more about the Exposed Cranium nebula and see another view of it from Webb’s MIRI (Mid-Infrared Range Instrument).

Image credit: NASA, ESA, CSA, STScI; Image Processing: Joseph DePasquale (STScI)