Specialists studying these stars often refer to them as super AGB stars, since they have many properties in common with AGB such as thermal pulsing.Others describe them as low-mass supergiants since they start to burn elements heavier than helium and can explode as supernovae.Asymptotic-giant-branch (AGB) and post-AGB stars are highly evolved lower-mass red giants with luminosities that can be comparable to more massive red supergiants, but because of their low mass, being in a different stage of development (helium shell burning), and their lives ending in a different way (planetary nebula and white dwarf rather than supernova), astrophysicists prefer to keep them separate.The dividing line becomes blurred at around 7–10 ) where stars start to undergo limited fusion of elements heavier than helium.Supergiant spectra are frequently annotated to indicate spectral peculiarities, for example B2 Iae or F5 Ipec.Supergiants can also be defined as a specific phase in the evolutionary history of certain stars.Smash workplace dining offers quality food storage and transport products to help you eat quality, home prepared meals, and in a little more style than traditional food storage or take-away containers.
Supergiants are also evolved stars with higher levels of heavy elements than main-sequence stars.
Although it was not known at the time, these were the most luminous stars.
Supergiants occur in every spectral class from young blue class O supergiants to highly evolved red class M supergiants.
Supergiant stars occupy the top region of the Hertzsprung–Russell diagram with absolute visual magnitudes between about −3 and −8.
The temperature range of supergiant stars spans from about 3,450 K to over 20,000 K.
Stars with initial masses above 8-10 quickly and smoothly initiate helium core fusion after they have exhausted their hydrogen, and continue fusing heavier elements after helium exhaustion until they develop an iron core, at which point the core collapses to produce a Type 2 supernova.