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
Hydrogen sulfide near a gas and oil drilling operations, ordinary citizens can be exposed to hydrogen sulfide by being near waste water treatment facilities, landfills and farms with manure storage. Exposure occurs through breathing contaminated air or drinking contaminated water. A number of processes designed to remove hydrogen sulfide from drinking water. Hydrogen sulfide is commonly found in raw natural gas and biogas. It is typically removed by amine gas treating technologies. In such processes, the hydrogen sulfide is first converted to an ammonium salt, whereas the natural gas is unaffected. The bisulfide anion is subsequently regenerated by heating of the amine