Discover the Breathtaking New Glimpse of the Andromeda Galaxy Captured by Hubble!

The Hubble Space Telescope, which orbits Earth, has unveiled the most extensive astronomical examination of Andromeda, the nearest galaxy to our Milky Way. This remarkable image was compiled from 600 individual fields of view, consists of over 2.5 billion pixels, and required more than ten years to compose.

Unveiled last week during a conference of the American Astronomical Society and subsequently published in The Astrophysical Journal, this new “photomosaic” also provides insight into the evolutionary background of our neighboring galaxy.

“One of Hubble’s enduring accomplishments is how it revealed the marvels of the cosmos to the public,” Kenneth Sembach, an astronomer at the Space Telescope Science Institute, mentioned to National Geographic’s Daniel Stone in 2020. His observation remains relevant now, nearly half a decade later.

At a distance of 2.5 million light-years, the Andromeda Galaxy—officially designated Messier 31—is the furthest object observable by the unaided eye. It manifests as a blurred cigar shape in the sky on clear, dark nights.

The photographic mosaic resulted from the collaboration of two Hubble initiatives that extended over a decade and involved more than 1,000 orbits around Earth. The Panchromatic Hubble Andromeda Treasury concentrated on the northern section of the galaxy, while its counterpart, the Panchromatic Hubble Andromeda Southern Treasury, documented the southern half. The final composition shows the galaxy tilted at a 77-degree angle compared to our perspective from Earth.

“Thanks to Hubble, we can explore remarkable detail regarding the events occurring on a grand scale across the entire disk of the [Andromeda] galaxy. No other large galaxy allows us to achieve such depth,” remarks Benjamin Williams, an astronomer at the University of Washington and principal investigator of the project, in a statement.

In fact, this imagery may provide insights into Andromeda’s past, potentially involving historical mergers with galaxies and nearby galactic interactions.

“Andromeda resembles a train wreck. It seems to have undergone an event that led to a substantial formation of stars and then a halt,” comments Daniel Weisz, an astronomer at the University of California, Berkeley, in a statement from NASA. “This was likely caused by a collision with another galaxy in the vicinity.”

“This intricate examination of the resolved stars will assist us in piecing together the galaxy’s previous merger and interaction timeline,” adds Williams.

Yet, Hubble has its constraints—the space telescope is only capable of identifying stars that shine brighter than our sun. In the Andromeda image, it highlighted more than 200 million stars; however, that still represents a fraction of the one trillion stars that astronomers estimate comprise the galaxy’s stellar inhabitants.

Nevertheless, our understanding of Andromeda has significantly evolved. Approximately a century ago, American astronomer Edwin Hubble identified our neighboring spiral galaxy. Prior to this discovery, scientists believed the entire universe was encompassed within the Milky Way, according to NASA. However, upon realizing Andromeda was an independent galaxy, astronomers acknowledged the universe’s vastness was far greater than they had assumed.

2.5 Billion Pixel Image of Galaxy Shot by Hubble

Much like the recent Andromeda revelations, Edwin Hubble’s finding was officially proclaimed during a meeting of the American Astronomical Society in January 1925. Nonetheless, the astronomer had previously leaked…the details to the New York Times in November of the preceding year, as reported by Space.com’s Keith Cooper, hence the scientific community—as well as the broader world—was already abuzz with enthusiasm.

“A century is not that distant,” Jeff Rich, an astrophysicist at the Carnegie Science Observatories, remarked during the recent American Astronomical Society gathering, according to Space.com. “This truly illustrates how significantly things have transformed and how discoveries can emerge rapidly.”

Similarly, this photomosaic of Andromeda probably signals not a conclusion, but the beginning of another century of astronomical revelations. With NASA’s James Webb Space Telescope and the forthcoming Nancy Grace Roman Space Telescope, upcoming observations may disclose even more about our astonishing cosmic companion.