The Andromeda galaxy, located 2.5 million light-years away, is the Milky Way’s nearest large galactic neighbor. A recent survey using the NASA/ESA Hubble Space Telescope has created a colorful portrait of the galaxy, capturing the glow of 200 million stars. The data collection took over 10 years and consisted of more than 600 snapshots.
The Hubble Space Telescope resolved 200 million stars in the galaxy, detecting only those brighter than our Sun. However, with an estimated one trillion stars in total, many less massive stars fell below Hubble’s sensitivity limit.
University of Washington astronomer Zhuo Chen and colleagues conducted a comprehensive survey to photograph the Andromeda galaxy. The effort required over 1,000 Hubble orbits spanning more than a decade.
The Panchromatic Hubble Andromeda Treasury (PHAT) program started about a decade ago, followed by the Panchromatic Hubble Andromeda Southern Treasury (PHAST), which added images of approximately 100 million stars in the southern half of the galaxy. The combined surveys cover the entire disk of Andromeda, assembled from over 600 fields of view.
The results, published in the Astrophysical Journal, provide new insights into the galaxy’s merger history and structural uniqueness.
Source: https://www.sci.news/astronomy/hubbles-photomosaic-andromeda-galaxy-13592.html