Chuck Bednar for redOrbit.com – Your Universe Online
A massive, high-definition panorama taken by the Hubble Space Telescope is being called the largest picture ever taken, and it shows Andromeda in unprecedented detail, depicting over 100 million individual stars and traversing a 48,000 light-year-long stretch of the galaxy.
The panorama is a gargantuan 1.5 billion-pixel image that requires more than 4 GB worth of disk space and is comprised of 411 individual Hubble images. In addition, it is the sharpest large-scale composite of Andromeda image ever captured, according to NASA, with 100 million-plus stars depicted in the image.
To put that into perspective, the European Space Agency said that the image is so big that it would take more than 600 high-definition TV screens in order to display the whole thing. According to the ESA, the panorama is the largest Hubble image ever released, and it has also established a new benchmark for the precision studies of large spiral galaxies.
Andromeda, also known as M31, is the closest galaxy to our own Milky Way. It is more than two million light years away, but the US space agency said that Hubble is powerful enough to resolve individual stars in a 61,000-light-year-long stretch of its pancake-shaped disk. NASA compares it to photographing a beach and being able to pinpoint individual grains of sand.
“Never before have astronomers been able to see individual stars inside an external spiral galaxy over such a large contiguous area,” NASA said. The image, which was presented earlier this month at the 225th Meeting of the Astronomical Society in Seattle, Washington, is “the first data to reveal populations of stars in context to their home galaxy,” the agency added.
The Hubble telescope traced densely packed stars that extended from the galaxy’s innermost region. Moving out from the center, the panorama sweeps across rows of stars and dust to the sparse outer disk. Large group of young blue stars indicate regions of star formation and star clusters, and the dark silhouettes indicate complex dust structures. Underlying the entire galaxy is a distribution of cooler red stars that trace the evolution of the galaxy over a period of several billion years, the researchers said.
The panorama was the product of the Panchromatic Hubble Andromeda Treasury (PHAT) program, and images were obtained by viewing Andromeda in near-ultraviolet, visible, and near-infrared wavelengths.
The individual exposures were captured using the Advanced Camera for Surveys in red and blue filters and the Wide Field Camera 3 aboard Hubble.
Hubble has been quite successful this month. Earlier this month, the space telescope revisited the site of one of its most iconic images, the three giant columns of cold gas known as the “Pillars of Creation,” to commemorate its 25th anniversary. The new images were said to be sharper and wider than the original ones, which went on to be featured in movies and TV shows and on t-shirts, pillows and even postage stamps.
Here’s lookin’ at you, Hubble. We’re looking forward to more jaw-dropping images from you in the near future.