Call it a snapshot, if you must, but it's still hard not to be impressed by the largest picture ever taken by the Hubble Space Telescope, a 1.5-billion-pixel view of the Andromeda Galaxy.

The highest-resolution photo ever captured of space has 1,000 times the resolution of a normal high-definition picture, and displaying the entire photo would require the equivalent of 750 HD television screens, researchers at the University of Washington who took the photo say.

Andromeda, just 2.5 million light years away from our own Milky Way Galaxy home -- a near neighbor in cosmic terms -- was chosen as the ideal candidate for the high-resolution image, and the resulting image is a new benchmark for precise study of a large spiral galaxy, astronomers say.

Even from millions of light years away, the strength of the Hubble telescope is enough to show individual stars within a 61,000-light-year-long swathe of the galaxy's pancake-shaped disk.

"Never before have astronomers been able to see individual stars inside an external spiral galaxy over such a large contiguous area," NASA says on its website.

"Most of the stars in the universe live inside such majestic star cities, and this is the first data that reveal populations of stars in context to their home galaxy."

The final image, which was presented earlier this month at the at the 225th Meeting of the Astronomical Society in Seattle, Washington, took 3 years to create as a composite of 7,398 separate images captured by Hubble from 411 points in space.

The level of detail in the image, which shows 100 million stars, is "like photographing a beach and resolving individual grains of sand," NASA said.

The photo can be downloaded from NASA's Hubble site, allowing individuals to zoom in and out on the image of a 61,000 light year-long panorama of Andromeda.

At the left edge of the panorama is the innermost hub, or bulge, of the galaxy, and moving to the right in the image reveals lanes of stars and dust that get progressively thinner in Andromeda's outer disk.

Dark silhouettes are evidence of complex dust structures, while an underlying even distribution of cool red stars traces the evolution of Andromeda over billions of years.

The image was created by instruments aboard Hubble viewing the galaxy in visible, near-ultraviolet and near-infrared wavelengths.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency and is managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland.