A team of astronomers has received hints that a long-time assumption related to evolution of galaxies is not correct, according to a recent article dubbed "The Epoch of Disk Settling: z ~ 1 to Now" published in the Astrophysical Journal.

The observations determine the stars' motions as well as those of the gas inside the distant galaxies. It is being said that spectroscopic observations of galaxies alone do not hint the opposite as assumed till date. But, supercomputer simulations, which helped to interpret the observations, have also been signifying the same.

The observations were made with the 10-meter telescopes atop the W. M. Keck Observatory on Hawaii. These were then combined with the Hubble Space Telescope's captured images and simulations.

It was believed that distant galaxies are no different from the ones nearby. Since, the rates of formation of stars in the Universe indicated that disk galaxies had finished developing some 8 billion years ago. But, the new study says that the motions of stars and gas have continued to settle down over these 8 billion years.

"Disk galaxies are well ordered: there is a defined plane and most stars revolve in one direction around its center. Very few stars or clouds of gas have non-circular motions", said a postdoctoral fellow at NASA's Goddard Space Flight Center Dr. Susan A. Kassin.