Cosmic Hawk Nebula Revealed in New VLT Infrared Image

An infrared image of the RCW 36 nebula, obtained with the Very Large Telescope, provides new details about a region of active star formation in the constellation Vela. The nebula’s structure and stellar content are of interest to astronomers studying how stars and substellar objects form.

The HAWK-I instrument, used for this observation, operates in infrared wavelengths and uses adaptive optics to enhance image clarity. This technology allows astronomers to detect faint objects, such as brown dwarfs, within the nebula’s dense clouds.

RCW 36 is situated within the Vela Molecular Ridge, one of the closest massive star-forming complexes to the Solar System. The nebula is classified as an emission nebula and H II region, and it contains a young open cluster with two massive late-O or early-B type stars and hundreds of lower-mass stars.

The structure of RCW 36 features dark clouds and filaments that create a hawk-like shape, with a blue region below representing a stellar nursery where new stars are forming. The nebula also displays a bipolar or hourglass morphology and is embedded within a specific clump of the Vela Molecular Ridge.

What the numbers show

• RCW 36 is located approximately 2,300 light-years from Earth
• A recent study revised its distance to about 3,110 light-years (954 ± 40 parsecs
• The star-to-brown-dwarf ratio in the cluster is estimated at 2–5

Research using HAWK-I and archival data has provided updated measurements of RCW 36’s distance and stellar population. The initial mass function of the cluster has been characterized down to about 0.03 solar masses, allowing for detailed study of both stars and brown dwarfs.

Brown dwarfs in RCW 36 are of particular interest because they form in a similar way to stars but do not have enough mass for hydrogen fusion. The HAWK-I instrument’s sensitivity in the infrared makes it possible to identify these faint objects within the nebula.

A recent study also identified possible primordial mass segregation in RCW 36, indicating differences in the distribution of stellar masses within and beyond a radius of 0.2 parsecs. This finding provides further insight into the early stages of cluster development.

Overall, the new image and associated research contribute to a better understanding of the processes occurring in one of the nearest regions of massive star formation to the Solar System. The data collected from RCW 36 continues to inform studies of stellar and substellar evolution in young clusters.

* This article is based on publicly available information at the time of writing.