Astronomers have unveiled the largest photomosaic of the Andromeda galaxy, assembled from over 600 snapshots taken by NASA/ESA’s Hubble Space Telescope. The colorful portrait captures the glow of 200 million stars and reveals new clues to the evolutionary history of this neighboring galaxy. Spanning 2.5 billion pixels, the mosaic is spread across a vast region of space.
The Andromeda galaxy, also known as Messier 31, has been studied for over a century by astronomers like Edwin Hubble, who first established its distance from our Milky Way galaxy in the early 20th century. Since then, observations have revealed that the galaxy’s evolutionary history differs significantly from our own Milky Way.
The new Hubble survey provides detailed information about the age, heavy-element abundance, and stellar masses inside Andromeda. This will allow astronomers to distinguish between competing scenarios of the galaxy’s merger history and disk evolution.
Researchers believe that a compact satellite galaxy, Messier 32, may have played a role in shaping Andromeda’s recent star-formation activities. Computer simulations suggest that close encounters with other galaxies can lead to a decrease in interstellar gas, causing star formation to subside.
Hubble’s findings will support future observations by the James Webb Space Telescope and provide new insights into the structure and evolution of our universe. The telescope’s sharp imaging capabilities have allowed astronomers to detect stars brighter than our Sun, providing a wealth of information about this vast galaxy.
Source: https://www.esa.int/Science_Exploration/Space_Science/Hubble_traces_hidden_history_of_the_Andromeda_Galaxy