A century ago, American astronomer Edwin Hubble was the first to prove that this so-called “spiral nebula” lies about 2.5 million light-years away from the Milky Way. To date, the NASA/ESA Hubble Space Telescope has achieved the most comprehensive survey of the Andromeda Galaxy. It took more than 10 years to collect the data. This colorful portrait which captures the glow of 200 million stars and was created from over 600 snapshots.
This is the largest photomosaic ever assembled from Hubble observations. A panoramic view of the neighboring Andromeda galaxy, 2.5 million light years away. Image credit: NASA/ESA/B. Williams, University of Washington.
The Andromeda Galaxy (Mesier 31) is located 2.5 million light-years away and is the closest large galaxy neighbor to the Milky Way.
Hubble's sharp imaging power can resolve more than 200 million stars in the galaxy and detect only those stars brighter than the Sun. They look like grains of sand on a beach. But that's just the tip of the iceberg.
Andromeda's total population is estimated to be 1 trillion stars, with many less massive stars falling below Hubble's sensitivity limit.
“Imaging the Andromeda Galaxy was a difficult task because it is a much larger target than the galaxies that Hubble regularly observes, often billions of light years away,” Washington said. said university astronomer Zhuo Chen and colleagues.
“The complete mosaic was performed under two Hubble observing programs. In total, it required more than 1,000 Hubble orbits spanning more than 10 years.”
“This panorama… Panchromatic Hubble Andromeda Treasury (PHAT) Program About ten years ago. ”
The Andromeda Galaxy is tilted 77 degrees to Earth's perspective and is seen almost head-on. Areas of interest include (a) a photobombing of bright blue clusters of stars embedded within the galaxy, background galaxies visible in the distance, and some bright foreground stars that are actually within the Milky Way; Masu. (b) NGC 206 is Andromeda's most prominent nebula. (c) A young population of newborn blue stars. (d) Satellite galaxy M32. This could be the remnant nucleus of a galaxy that once collided with Andromeda. (e) A dark dust band across countless stars. Image credit: NASA/ESA/B. Williams, University of Washington.
“Images were acquired at near-ultraviolet, visible, and near-infrared wavelengths. Hubble's advanced survey camera (ACS) and wide field camera 3 (WFC3) To photograph the northern half of Andromeda. ”
“The follow-up of this program is Panchromatic Hubble Andromeda Tropical Treasury (PHAST), added images of about 100 million stars in the southern half of Andromeda. ”
“This region is structurally unique and more sensitive to the history of galactic mergers than the northern disk mapped by the PHAT survey.”
“The combined program collectively covers Andromeda's entire disc, which is tilted 77 degrees to Earth's field of view and viewed almost head-on.”
“The galaxy is so large that the mosaic is assembled from about 600 separate fields of view.”
of result described in the paper. astrophysical journal.
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Zhuo Chen others. 2025. Fast. Panchromatic Hubble Andromeda Southern Treasury. I. Ultraviolet and optical photometry of over 90 million stars in M31. APJ 979, 35;doi: 10.3847/1538-4357/ad7e2b
Source: www.sci.news
