Asymptotic giant branch forming helium (known as hydrogen burning), and a very large envelope of material of composition similar to main-sequence stars. When a star exhausts the supply of hydrogen by nuclear fusion processes in its core, the core contracts and its temperature increases, causing the outer layers of the star to expand and cool. The star becomes a red giant, following a track towards the upper-right hand corner of the HR diagram. Eventually, once the temperature in the core has reached approximately , helium burning (fusion of helium nuclei) begins. The onset of helium burning in the core halts the star's cooling
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