ESA Researchers Discover Several Galaxies Through Infrared Telescope

Researchers from University of Sussex have discovered that three or four galaxies are responsible for the glow of heated dust reaching our planet, opposing the commonly assumed thought that the dusty glow is only coming from one galaxy.

According to the study published in the Monthly Notices of the Royal Astronomical Society, this discovery may help the researchers further understand the relationship of galaxies that are close together. Their findings also added billions of galaxies that are not yet known.

Due to the far-infrared observations of the European Space Agency's Herschel Space Observatory the images that were produced are in low resolution, making objects detected by the Hershel to be blurred over an area about 26 times as large as the Milky Way Galaxy. This abundance of galaxies are making it difficult for researchers to pinpoint the one responsible for the dust glow.

To overcome this difficulty, researchers reevaluated the numbers of dusty galaxies that exist using new statistical methods. These new methods were also used in order to determine the best possible way to split up the light detected by Herschel in accordance to the positions of previously known nearby galaxies.

Using the new statistical method, the researchers then theorized that one galaxy is responsible for the glowing dust if it is located in the exact center of the dust glow, while more than one galaxy is responsible for the dust glow if there are no galaxy found in the middle and if the glow is not perfectly round.

The researchers used this method in 360 objects detected at 250 micron by Herschel within the COSMOS field. Upon crunching all the data, researcher found out that 95 percent of the sampled objects were made out of at least two dust-bright galaxies hiding within the low-resolution images from Herschel.

"Even after being revealed as multiple galaxies, each galaxy is still very bright, and forming a lot of new stars. The fact that there are several bright galaxies so close to each other on the sky may mean that they're interacting with each other, which might help explain how they got so bright in the first place," said Dr Jillian Scudder, lead author and Postdoctoral Research Fellow in Astrophysics, in a statement.