Astronomers Image Barnard's Galaxy

A new image, released by the European Southern Observatory (ESO), reveals the glow of the elusive galaxy NGC 6822, which is a companion of the Milky Way, and a member of the local galactic group. The formation is visible as a glow beneath the layer of stars that can be found in the immediate vicinity of our own galaxy. The 2.2-meter MPG/ESO telescope at the ESO La Silla Observatory, in northern Chile, was used for these observations, which provide one of the best available pictures of the formation.

NGC 6822 was first discovered by American astronomer Edward Emerson Barnard, in 1884. The scientist used a 125-millimeter aperture refractor to make out the dwarf galaxy, which is located some 1.6 million light-years away, in the direction of the constellation Sagittarius (the Archer). It does not have spirals or a glowing central region – such as the Milky Way, Andromeda and the Triangulum galaxies do –, but it doesn't come up short when displaying fireworks and highly active processes.

In the new photograph, which was snapped using the Wide Field Imager (WFI) instrument, reddish nebula regions are clearly visible within Barnard's Galaxy, hinting at areas of intense stellar formation. In these regions, young, blue stars heat up the gas around them, generating the hellish, red glow. The image also reveals, in its upper-left part, a peculiar, bubble-shaped nebula, a very rare class of cosmic structures. A clutch of massive, scorching stars adorns the galactic core, and the energy waves it generates slam at great speeds into the interstellar matter around it.

NGC 6822 does not contain more than ten million stars, experts say, which means that it falls under the dwarf-galaxy classification criterion. It is only one tenth the size of the Milky Way, which is estimated to contain about 400 billion stars altogether. Generally speaking, throughout the Universe, there are definitely more dwarf galaxies such as Barnard's than there are massive ones, like the Milky Way. The formation draws its peculiar shape from the fact that it has repeatedly collided with other galaxies, which made it lose a lot of stars.