The gas in a region of a fragmenting molecular cloud forms an irregular blob about 100 times the size of our solar system and rises in temperature to about 100 K.
The central temperature rises well above 10,000 K, and a photosphere forms.
The central temperature climbs to about 1000 K, and the condensing gas cloud begins to form into a roughly spherical shape.
The central temperature rises to about 10,000,000 K, and nuclear fusion begins.
The central temperature levels off at about 15,000,000 K, and the nuclear fusion rate stabilizes.