Researchers from the Instituto de Astrofísica de Canarias (IAC) and the University of Padua (Italy) have found that the Milky Way was built very quickly. Research is based on the age of the ancient stars or clusters of the galaxy. It seems that all these clusters were formed almost at the same time, between 500 and 1,000 million years. With this data, they have concluded that the Milky Way was constituted in the same season. 1,000 million years represents 5% of the age of the Milky Way, a very short season. There are also theories that affirm that the Milky Way was built much more slowly, and consider that our galaxy took between 4,000 and 5,000 million years to acquire its present aspect. In the last 50 years, researchers have moved from one theory to another. On occasions, discoveries were made that fostered rapid training and in others, slow training was chosen. The discovery of the astrophysicists of the Canaries and Padua has reopened a debate.