This high definition panoramic view of the spiral Andromeda (M31) galaxy, extending from the central hub to the outer fringes of the disk, is being described by NASA as the “sharpest large composite image” of our galactic neighbor ever captured.
The image, with a resolution of 1.5 billion pixels, taking up about 4.3 GB of disk space, is also being touted as the largest photo ever taken.
The YouTube video, uploaded by “daveachuk” on Jan. 6, 2015, provides an animated version of the image that affords an opportunity to appreciate the gigantic scale of the galactic structure captured in a single panoramic swoop.
The video has been viewed more than 5 million times since it was uploaded to YouTube.
With the image, the Hubble Space Telescope demonstrates its ability to resolve more than 100 million individual stars in a stretch of the Andromeda galaxy spanning 61,000-light years. The view shown in the photo, captured using Hubble’s Advanced Camera for Surveys in red and blue filters, is a 48,000-light-year-long chunk of the entire 61,000-light-year-long panorama. It shows the galaxy in its natural, visible-light color.
Astronomers have never been able to see so clearly individual stars distributed in multiple clusters over a large expanse of a spiral galaxy at once. This is the first time that astronomers are able to observe individual stars in the grand context of their galactic environment.
According to NASA, the feat is comparable to a photograph resolving individual grains of sand on a beach — an incredible accomplishment of photographic mapping for a subject about 2 million light years away.
The image is a composite constructed from 7,398 separate exposures taken from more than 411 points using Hubble’s Advanced Camera for Surveys and the Wide Field Camera 3. The cameras viewed the galaxy in several wavelengths, including near-ultraviolet, visible, and near-infrared.
The high definition panorama extends from left of the image, showing the star-studded inner hub of the galaxy with a distinct egg yolk-like bulge, across intermediate sections with myriads of star clusters and galactic dust, to the more sparsely populated outer sections of the disk on the right.
Bluish formations with ring-like structures to the right side of the image represent clusters of young stars contiguous with active regions where new stars are being born. These alternate with dark structures representing areas of galactic dust and gas.
Older and cooler red stars at various stages of their life cycles, which have helped astronomers and astrophysicists construct the life cycles of stars and the histories of galaxies spanning billions of years, show a more even distribution.
The HD panorama was completed under the Panchromatic Hubble Andromeda Treasury (PHAT) program. Andromeda was a convenient subject for photographic mapping, being the nearest galaxy to our Milky Way at a distance of only 2.5 million light-years, compared with other galaxies billions of light-years away, that Hubble has photographed.
The remarkable achievement sets new standards for ongoing efforts at photographic mapping of the over 100 billion spiral galaxies in the visible universe.
Hubble Space Telescope is a joint project of NASA and the European Space Agency (ESA). It is being managed by the Goddard Space Flight Center in Greenbelt, Maryland.