Lambda Velorum apparent magnitudes +2.14 to +2.30. λ Velorum is an evolved star that has exhausted the hydrogen in its core region. It has about seven times the mass of the Sun. It is likely to be on or approaching the asymptotic giant branch (AGB), although its properties do not exclude it being a slightly more massive star on the red giant branch (RGB). As an AGB star it has an inert core of carbon and oxygen and is alternately fusing helium and hydrogen in two shells outside the core. The star's outer envelope has expanded to form a deep, convective, hydrogen
Red-giant branch core becomes degenerate. The core still supports its own weight thermodynamically with the help of energy from the hydrogen shell, but is no longer in thermal equilibrium. It shrinks and heats causing the hydrogen shell to become thinner and the stellar envelope to inflate. This combination decreases luminosity as the star cools towards the foot of the RGB. Before the core becomes degenerate, the outer hydrogen envelope becomes opaque which causes the star to stop cooling, increases the rate of fusion in the shell, and the star has entered the RGB. In these stars, the subgiant phase occurs within a