Why in news?
Astronomers from the Aryabhatta Research Institute of Observational Sciences (ARIES), have recently mapped in detail the invisible layers of cosmic dust that form a veiling "dusty veil" over the Milky Way. 
 
What is the Dusting Veil?

• A Cosmic Curtain: The dusting veil is not a solid object but a collection of countless tiny dust grains, primarily composed of silicates, amorphous carbon, graphite, and polycyclic aromatic hydrocarbons (PAHs).
• Obscuring Our View: This veil of dust absorbs and scatters the light from distant stars and the bright center of the Milky Way, making them appear dimmer and redder. This phenomenon is known as interstellar extinction and reddening.
• The Great Rift: A prominent feature of this dusty veil is the Great Rift, a dark, seemingly empty band that appears to split the Milky Way in the night sky.

 Distribution and Structure

• Uneven and Wavy: Recent studies, have revealed that the dust is not uniformly distributed. It forms a thin, wavy layer that doesn't perfectly align with the central plane of the galaxy.
• Galactic Plane Concentration: The majority of this dust is concentrated within the galactic plane, the flat, disk-like region where most of the Milky Way's stars, gas, and dust reside.
• Variable Thickness: The thickness and density of the dust layer vary across the galaxy. It is generally denser towards the galactic center.  

Role in Star and Planet Formation

• Stellar Nurseries: Despite obscuring our view, these dust clouds are essential for the formation of new stars. Dense regions within these clouds, known as molecular clouds, are the birthplaces of stars.
• Shielding and Cooling: The dust shields the gas within these clouds from the harsh radiation of nearby stars, allowing it to cool down and collapse under its own gravity, the first step in star formation.
• Building Blocks of Planets: The dust grains themselves are the fundamental building blocks of planets. In the protoplanetary disks surrounding young stars, these grains stick together to form larger and larger bodies, eventually leading to the formation of planets, asteroids, and comets. 

The dusting veil of the Milky Way is a dynamic and vital component of our galaxy. While it hides much of the cosmos from our direct view, it is also the very material from which new stars and planetary systems are born.

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