# FAST telescope neutral hydrogen survey

> Live situation record from CLSTR: https://clstr.news/situations/fast-telescope-neutral-hydrogen-survey
> Updated: 2026-09-13T12:00:08.000Z. Sources: 5. Developments: 2.

China’s Five-hundred-meter Aperture Spherical Telescope (FAST) has completed a major astronomical survey, producing the world’s largest atlas of neutral hydrogen sources. The FAST All-Sky H I Survey (FASHI) identified 156,411 sources, covering approximately 19,500 square degrees of the sky.

This dataset represents a significant advancement over previous records, including the US Arecibo Telescope’s ALFALFA survey. The findings, published in Science China Physics, Mechanics & Astronomy, allow for the detection of galaxies that are smaller, fainter, and more distant than previously recorded. 

Researchers from the National Astronomical Observatories of the Chinese Academy of Sciences indicate that the data will assist in studying cosmic structures, dark matter distribution, and galaxy evolution. The survey is expected to serve as a global reference and bridge research gaps for future projects such as the Square Kilometre Array.

## Timeline

### 2026-09-13: FAST telescope detects over 156,000 neutral hydrogen sources

China’s FAST telescope has detected 156,411 neutral hydrogen sources, creating a massive new cosmic catalogue that surpasses previous US surveys in scale and detail.

2 sources. https://clstr.news/cluster/fast-telescope-detects-over-156000-neutral-hydrogen-sources

### 2026-09-09: FAST telescope compiles world's largest atlas of neutral hydrogen

China's FAST telescope has created the world's largest atlas of neutral hydrogen sources, detecting over 156,000 sources to help scientists study galaxy formation and cosmic evolution.

3 sources. https://clstr.news/cluster/fast-telescope-compiles-worlds-largest-atlas-of-neutral-hydrogen

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Cite as: FAST telescope neutral hydrogen survey. CLSTR, https://clstr.news/situations/fast-telescope-neutral-hydrogen-survey