Galaxies are customarily found to be in constant motion. Their motion is in the form of a twirling disc. It has recently been discovered that a disc galaxy is found to have stopped making stars. It was found that stars evolved from the disc shaped galaxies much less than from spiral shaped galaxies like our Milky Way.
Evolution of disc-shaped galaxies
The dead galaxies are found to have evolved from spiral galaxies into the disc shaped galaxies that are seen now-a-days. Elliptical galaxies have old stars and do not make new ones while the spiral galaxies have blue stars which are comparatively quite young. The dead disc galaxies changed their motion and also changed their structure from spiral to disc shape.
The structure of the dead galaxies is smaller than the elliptical galaxies into which they will soon evolve. Scientists have used the technique of gravitational lens to look deeper into the center of a dead galaxy. The European Southern observatory has found that this dead galaxy is rotating with a velocity twice more than the speed of Milky Way.
Speculations over this galaxy being dead
The reason of why this galaxy has stopped making stars is still unknown. The speculations are that probably the massive black hole at the center of this galaxy has caused its mass to reduce or probably the cold gas has compressed and heated up, not allowing it to cool down to form stars.
A scientist named, Toft, believe that the galaxy has probably merged with the minor galaxies to turn into an elliptical galaxy. The star orbits would become random and the galaxy would change its shape. As he said, “If these galaxies grow through merging with minor companions, and these minor companions come in large numbers and from all sorts of different angles onto the galaxy, this would eventually randomize the orbits of stars in the galaxies. You could also imagine major mergers. This would definitely also destroy the ordered motion of the stars.”
Scientists and astronomers are working on latest technology to find ways to discover more unknown and strange phenomenon in the universe.