When it reaches 1.38 times the mass of our Sun, gravity wins and the material can no longer stop from falling inwards so the star tries to starts to collapse.
Inapofika mara 1.38 ya uzito wa Jua letu, nguvu ya uvutano inashinda na nyenzo haiwezi tena kuacha kuanguka ndani kwa hivyo nyota inajaribu kuanza kuanguka.