New Catalog of 1,573 Molecular Clouds with Accurate Distances Compiled from MWISP Survey
A team of researchers has determined accurate distances to 1,573 molecular clouds in the Milky Way, with 90 percent of these measurements made for the first time. The study used three independent methods matching CO emission maps from the MWISP survey against 3D dust extinction maps derived from Gaia, Pan-STARRS 1, and 2MASS data, covering clouds between roughly 150 and 3,000 parsecs away. The publicly available catalog provides a foundational resource for studying star formation conditions and Galactic spiral structure across diverse environments.
Researchers have produced a catalog of 1,573 molecular clouds with robustly determined distances, drawn from a parent sample of 103,517 clouds identified via the DBSCAN clustering algorithm in the MWISP Phase I CO survey, which spans Galactic longitudes of 9.75 to 229.75 degrees within ±5.25 degrees of the Galactic plane. Three independent distance-estimation methods were applied, each cross-matching velocity-integrated 12CO intensity maps with three-dimensional dust extinction maps constructed from Gaia, Pan-STARRS 1, and 2MASS photometry. The resulting distances range from approximately 150 to 3,000 parsecs, with typical statistical uncertainties of about 20 percent and systematic uncertainties of about 10 percent. In addition to distances, the study derives physical properties including cloud masses and sizes, enabling tests of molecular cloud scaling relations. The catalog has been accepted for publication in The Astrophysical Journal Supplement Series and is publicly available, offering a broad empirical basis for investigating how cloud conditions shape star formation across the Galaxy.
What's missing
The study covers only the MWISP Phase I footprint and delivers robust distances for roughly 1.5 percent of the full 103,517-cloud sample.
What different sources said
- arXiv astro-phCenter
A study of the Physical Properties and Star Formation Activity of a Large Sample of Molecular Clouds: I Distances
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