Astronomers uncover hidden ‘river of gas’ streaming toward Milky Way’s core

A team of international astronomers has unveiled a massive, previously unknown cloud of gas and dust streaming toward the heart of the Milky Way.

Dubbed the Midpoint cloud, this structure spans 200 light-years and provides a rare glimpse into how material moves through the galaxy and fuels star formation near its core.

With the help of the National Science Foundation’s Green Bank Telescope (GBT), Midpoint cloud (M4.7-0.8) has been identified as a Giant Molecular Cloud (GMC).

GMC is a massive and dense region where stars are formed. Mainly, these clouds are composed of molecular gas (such as hydrogen and helium) and dust. They are usually referred to as the birthplaces of stars within galaxies.

Natalie Butterfield, lead author of the National Radio Astronomy Observatory (NRAO) stated: “One of the big discoveries of the paper was the GMC itself. No one had any idea this cloud existed until we looked at this location in the sky and found the dense gas. Through measurements of the size, mass, and density, we confirmed this was a giant molecular cloud.”

It is estimated that the GMC lies within one of the Milky Way’s dust lanes that act as cosmic rivers channelling gas toward the galactic center.

Butterfield further explained: “These dust lanes are like hidden rivers of gas and dust that are carrying material into the centre of our galaxy.”

Discussing the midpoint cloud, she stated: “The Midpoint cloud is a place where material from the galaxy’s disk is transitioning into the more extreme environment of the galactic center and provides a unique opportunity to study the initial gas conditions before accumulating in the center of our galaxy.”

The study also analyzes molecules such as ammonia (NH₃) and cyanobutadiyne (HC₅N).

The study found:

• A new maser (microwave laser) is related to star-forming regions.
• There are also dense gas clumps, including one possibly forming a free-floating evaporating gas globule (frEGG).
• Turbulent gas motions highlight violent interactions as material flows inward.

The discovery highlights the remarkable phenomenon of how galaxies funnel material to their cores and how extreme conditions influence star formation.

Future studies can unveil more about the Milky Way’s evolution and the dynamic processes shaping its center.