Giant star degenerate helium fusion begins explosively, but most of the energy goes into lifting the degeneracy and the core becomes convective. The energy generated by helium fusion reduces the pressure in the surrounding hydrogen-burning shell, which reduces its energy-generation rate. The overall luminosity of the star decreases, its outer envelope contracts again, and the star moves from the red-giant branch to the horizontal branch. When the core helium is exhausted, a star with up to about has a carbon–oxygen core that becomes degenerate and starts helium burning in a shell. As with the earlier collapse of the helium core, this starts
Red and white giant flying squirrel found in mountain areas, they nest in hollow trees. They move between the trees of their ecosystem by gliding by use of a patagium, typically over distances of 10–20 meters although glides of up to 400 meters longer have been observed when they happen to be traveling downhill. This species has a wide distribution and a presumed large population, it occurs in many protected areas, and the International Union for Conservation of Nature has rated it as being of "least concern". Red and white giant flying squirrel The red and white giant flying squirrel ("Petaurista alborufus") is a species of