Scientists have found a huge ultraviolet arc in the constellation Ursa Major. It extends thirty degrees – from the middle of the handle of the Dipper Bucket. This was written by a group of astronomers in their work, a preprint of which was published in

The study involved astronomers from France, the Netherlands and the United States under the leadership of Andrea Bracco from the Croatian Rugger Boskovich Institute. They studied an unusually direct and subtle ionized structure in the constellation Ursa Major, the first of which became known back in 2001.

It turned out that this structure in the images obtained by the GALEX telescope (Galaxy Evolution Explorer) is visible both in the far ultraviolet with a wavelength of 130-180 nanometers and in the near – 170-280 nanometers.


The thread consists of a large number of small arches that lie near the Ursa Major cavity, which is known as the region with the lowest density of neutral hydrogen according to the line of sight. Astronomers love this area because it is attractive for intergalactic research.

Scientists believe that the Ursa Major’s arc was formed as a result of a supernova explosion several hundred parsecs from the solar system. The arc consists of gas heated to a temperature of almost 10 thousand degrees Celsius.