Red-giant branch the star when it reaches the horizontal branch, so the properties of red-clump stars can be used to determine the mass difference before and after the helium flash. Mass lost from red giants also determines the mass and properties of the white dwarfs that form subsequently. Estimates of total mass loss for stars that reach the tip of the red-giant branch are around . Most of this is lost within the final million years before the helium flash. Mass lost by more-massive stars that leave the red-giant branch before the helium flash is more difficult to measure directly. The current
Red Spider Nebula complex way. The central white dwarf, the remaining compact core of the original star, produces a powerful and hot (≈10,000 K) wind blowing with a speed of 300 kilometers per second, which has generated waves 100 billion kilometres high. The waves are generated by supersonic shocks formed when the local gas is compressed and heated in front of the rapidly expanding lobes. Atoms caught in the shocks radiate a visible light. These winds are what give this nebula its unique 'spider' shape and also contribute to the expansion of the nebula. The star at the center of the Red Spider