Almost 55 percent of the star formation arises from minor mergers between galaxies, according to an astronomer who analyzed data collected as part of the Sloan Digital Sky Survey (SDSS). A Hubble image of the spiral galaxy NGC 7714, which has been dramatically distorted in shape by a close interaction with another nearby galaxy. Minor, but frequent, disturbances such as this cause a burst of star formation, accounting for around half of all new stars...
