Answer:
The sun was formed from the stars that have evolved after a definite period of time. The T-Tauri phase is the initial stage of the formation of the sun that was during its first few tens of millions of years. The mass of the sun at this stage was comparatively less than its present mass. The temperature also was relatively less and was not enough for nuclear fusion to take place and the sun was not so shiny at this time.
A huge amount of solar wind had released after the explosion of the star at its T-Tauri phase and after some millions of years, the sun took its present form, increasing its mass as well as the temperature.
