JWST observations unlock secrets of the mysterious dark region in Milky Way

Despite harbouring 56,000 stars, 'The Brick', with its mass equivalent to 60 million suns, displays far fewer stars than expected
The image shows an artists imagination of the Milky Way galaxy. — Freepik
The image shows an artist's imagination of the Milky Way galaxy. — Freepik

In the heart of the Milky Way galaxy lies an enigmatic dark cloud known as "The Brick." This dense, shadowy entity, replete with cold gas, has long confounded scientists due to its unexpectedly low rate of star formation, despite its ideal conditions for birthing stars. Recent observations from the James Webb Space Telescope (JWST) have shed new light on this cosmic anomaly.

Despite harbouring 56,000 stars, The Brick, with its mass equivalent to 60 million suns, displays far fewer stars than anticipated for a molecular cloud of its magnitude. Multiple factors could contribute to its apparent inactivity, including its youth, turbulence, or potent magnetic fields stifling star-forming processes.

Using JWST, researchers investigated the emission of carbon monoxide within the cloud and made a peculiar discovery — it predominantly exists in an icy state at the cloud's core, a revelation that significantly impacts future observations.

Astronomer Adam Ginsburg from the University of Florida emphasised, "Our findings undeniably highlight the prevalence of ice within The Brick, demanding its consideration in all future observations. JWST has opened novel avenues to study solid-phase molecules, complementing our prior focus on gaseous forms, thereby offering a comprehensive perspective on molecular distribution and transport."

However, the substantial ice presence doesn't elucidate the sluggish pace of star formation, contrary to expectations. Stars typically arise from cold gas, which condenses into denser regions and eventually collapses to form stars. While copious ice might imply lower temperatures within the cloud, the team made an intriguing discovery — the central gas of The Brick is warmer compared to analogous regions, presenting a crucial puzzle piece in understanding this molecular cloud.

These initial revelations, made possible by JWST, provide unprecedented insight into a longstanding astronomical enigma. The study, published in The Astrophysical Journal, marks the outset of extensive research into The Brick, promising further discoveries regarding its chemical composition and evolutionary trajectory.

"We aim to unravel the ratios of CO, water, CO2, and complex molecules, exploring the temporal evolution of chemistry within these clouds using spectroscopy," Ginsburg remarked, underscoring the ongoing quest to decode the mysteries encapsulated within The Brick.