Chandra Release - May 22, 2007

Visual Description: Andromeda Galaxy

 This image of the Andromeda galaxy appears as a large, bright spiral shaped galaxy in the left-center of the image, settled in a starry sky as shown in optical light.  In the lower right corner of the image, there is an inset showing an X-ray and optical image of the galaxy’s core region. X-rays from NASA's Chandra X-ray Observatory are colored in blue and combined with the optical image in whites and greys.  The blue X-rays are heavily speckled through the core of the galaxy, interspersed in a very slight spiral pattern. Astronomers believe that Andromeda, also known as M31, and the Milky Way will merge in a few billion years.  In the composite close-up image, hot, X-ray bright gas is seen to envelop the central region of Andromeda. Blue point sources are also prominent, mostly from pairs of stars that are interacting with each other.