An astronomer utilizing the Green Bank Telescope (GBT) has developed an extensive map of carbon monoxide (CO) and dark molecular gas in star-forming complexes, particularly in Cygnus X.
These images illustrate the location of CO-dark molecular gas within Cygnus X. Image credit: NSF/AUI/NSF’s NRAO/P.Vosteen.
For decades, scientists have recognized that most new stars are birthed in frigid clouds of molecular hydrogen gas.
A significant portion of this molecular hydrogen remains elusive to most telescopes as it fails to emit easily detectable light.
Astronomers have typically sought these clouds by examining carbon monoxide (CO), a molecule that serves as a glowing signal for star-forming regions.
However, it has been uncovered that CO houses a considerable amount of “non-glowing” gas conducive to star formation.
This concealed material, referred to as CO-dark molecular gas, has represented one of astronomy’s most significant blind spots.
In a fresh study, NRAO astronomer Kimberly Emig and her team mapped this hidden gas across extensive sections of the sky, using radio spectral lines from atomic recombination known as carbon radio recombination lines (CRRLs).
Their map encompasses Cygnus X, a star-forming region located approximately 5,000 light-years away in the constellation Cygnus.
“It’s akin to suddenly switching on a light in a room and discovering various structures that were previously unseen,” Dr. Emig remarked.
The newly constructed map unveils a sprawling network of arcs, ridges, and webs of dark gas permeating Cygnus X.
These formations indicate where star-forming materials accumulate and evolve before becoming noticeable as molecular clouds in CO.
The authors demonstrated that these faint carbon signals, observed at very low radio frequencies, serve as an extraordinarily powerful instrument for uncovering hidden gas that directly correlates ordinary matter with the birth of new stars.
They found that this dark gas is not static; instead, it flows, shifts, and moves at rates much faster than previously recognized. These dynamics influence the stellar formation rate.
Moreover, they discovered that the intensity of these carbon lines is directly connected to the intense starlight bathing the area, emphasizing the significant role radiation plays in galactic recycling.
“By illuminating the invisible, we can trace how the raw ingredients in our galaxy transform from simple atoms into complex molecular structures that will ultimately become stars, planets, and potentially life,” Dr. Emig stated.
“This marks merely the beginning of comprehending an otherwise unseen force.”
Find the results published in the October 17th edition of the Astrophysical Journal.
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Kimberly L. Emig et al. 2025. The cold dark gas of Cygnus X: the first large-scale mapping of low-frequency carbon recombination lines. APJ 992, 216; doi: 10.3847/1538-4357/adfa17
Source: www.sci.news
