April 30, 2024

Astronomers Find the Biggest Structure in the Milky Way: Filament of Hydrogen 3,900 Light-Years Long

About 370,000 years later, hydrogen had formed, the structure block of stars, which fuse hydrogen and helium in their interiors to create all the heavier elements. While hydrogen stays the most prevalent aspect in the Universe, it can be hard to detect specific clouds of hydrogen gas in the interstellar medium (ISM).
The isotopes include atomic hydrogen (H), composed of one proton, one electron, and no neutrons, and molecular hydrogen (H2) is made up of 2 hydrogen atoms held together by a covalent bond. The procedure of how atomic hydrogen transitions to molecular hydrogen is still mostly unidentified, which made this extraordinarily long filament a specifically interesting find. On closer inspection, the team saw that the gas assembles at numerous points along the filament, which led them to conclude that the hydrogen gas accumulates into big clouds at those locations.

The research is based upon data obtained by the HI/OH/Recombination line survey of the Milky Way (THOR), an observation program that depends on the Karl G. Jansky Very Large Array (VLA) in New Mexico. Using the VLAs centimeter-wave radio dishes, this task research studies molecular cloud development, the conversion of atomic to molecular hydrogen, the galaxys electromagnetic field, and other concerns associated with the ISM and star development.
The supreme purpose is to determine how the two most-common hydrogen isotopes assemble to produce thick clouds that increase to brand-new stars. The isotopes consist of atomic hydrogen (H), composed of one proton, one electron, and no neutrons, and molecular hydrogen (H2) is made up of two hydrogen atoms held together by a covalent bond. Just the latter condenses into fairly compact clouds that will develop frosty areas where brand-new stars eventually emerge.
The Galactic Centre of the Milky Way is suggested on the right of the image, shining brilliantly listed below the dark zone. The box to the left of the middle marks the place of the “Maggie” filament. It reveals the distribution of atomic hydrogen.
The procedure of how atomic hydrogen shifts to molecular hydrogen is still mainly unidentified, that made this extremely long filament an especially exciting discover. Whereas the largest recognized clouds of molecular gas usually measure around 800 light-years in length, Maggie determines 3,900 light-years long and 130 light-years broad. As Syed discussed in a recent MPIA press release:
The filament extends about 1600 light-years listed below the Milky Way airplane. The observations also permitted us to figure out the velocity of the hydrogen gas.
The teams analysis showed that matter in the filament had a mean velocity of 54 km/s -1, which they figured out primarily by determining it versus the rotation of the Milky Way disk. This indicated that radiation at a wavelength of 21 cm (aka. the “hydrogen line”) was noticeable versus the cosmic background, making the structure discernible. “The observations likewise permitted us to identify the speed of the hydrogen gas,” stated Henrik Beuther, the head of THOR and a co-author on the research study. “This allowed us to reveal that the speeds along the filament barely vary.”
This false-color image shows the distribution of atomic hydrogen determined at a wavelength of 21 cm. The red dashed line traces the “Maggie” filament. Credit: J. Syed/MPIA
From this, the researchers concluded that Maggie is a coherent structure. These findings validated observations made a year prior to by Juan D. Soler, an astrophysicist with the University of Vienna and co-author on the paper. When he observed the filament, he called it after the longest river in his native Colombia: the Río Magdalena (Anglicized: Margaret, or “Maggie”). While Maggie was recognizable in Solers earlier examination of the THOR data, only the current study shows beyond a doubt that it is a coherent structure.
Based on formerly released information, the group likewise estimated that Maggie consists of 8% molecular hydrogen by a mass portion. On closer examination, the team observed that the gas assembles at various points along the filament, which led them to conclude that the hydrogen gas accumulates into large clouds at those locations. They further speculate that atomic gas will gradually condense into a molecular type in those environments.
” However, numerous concerns remain unanswered,” Syed included. “Additional information, which we hope will give us more ideas about the portion of molecular gas, are currently waiting to be analyzed.” Several space-based and ground-based observatories will end up being operational quickly, telescopes that will be geared up to study these filaments in the future. These consist of the James Webb Space Telescope (JWST) and radio surveys like the Square Kilometer Array (SKA), which will enable us to view the really earliest duration of deep space (” Cosmic Dawn”) and the first stars in our Universe.
Originally released on Universe Today.
For more on this research, see Massive Filament Structure– 3900 Light-Years Long– Discovered in the Milky Way.
Recommendation: “The “Maggie” filament: Physical properties of a giant atomic cloud” by J. Syed, J. D. Soler, H. Beuther, Y. Wang, S. Suri, J. D. Henshaw, M. Riener, S. Bialy, S. Rezaei Kh., J. M. Stil, P. F. Goldsmith, M. R. Rugel, S. C. O. Glover, R. S. Klessen, J. Kerp, J. S. Urquhart, J. Ott, N. Roy, N. Schneider, R. J. Smith, S. N. Longmore and H. Linz, 20 December 2021, Astronomy & & Astrophysics.DOI: 10.1051/ 0004-6361/2021 41265.

Artists conception of the Milky Way galaxy. Credit: Pablo Carlos Budassi
Roughly 13.8 billion years back, our Universe was born in an enormous explosion that generated the very first subatomic particles and the laws of physics as we understand them. About 370,000 years later on, hydrogen had actually formed, the building block of stars, which fuse hydrogen and helium in their interiors to develop all the heavier aspects. While hydrogen stays the most pervasive aspect in deep space, it can be tough to identify individual clouds of hydrogen gas in the interstellar medium (ISM).
This makes it difficult to look into the early stages of star development, which would offer clues about the evolution of galaxies and the cosmos. An international group led by astronomers from the Max Planck Institute of Astronomy (MPIA) just recently noticed a huge filament of atomic hydrogen gas in our galaxy. This structure, called “Maggie,” is situated about 55,000 light-years away (on the other side of the Milky Way) and is among the longest structures ever observed in our galaxy.
The research study that describes their findings, which just recently appeared in the journal Astronomy & & Astrophysics, was led by Jonas Syed, a Ph.D. student at the MPIA. He was signed up with by researchers from the University of Vienna, the Harvard-Smithsonian Center for Astrophysics (CfA), the Max Planck Institute for Radio Astronomy (MPIFR), the University of Calgary, the Universität Heidelberg, the Centre for Astrophysics and Planetary Science, the Argelander-Institute for Astronomy, the Indian Institute of Science, and NASAs Jet Propulsion Laboratory (JPL).