Searching for Supernovae

A hunt for supernovae is a little different from normal variable star observing. Instead of observing a local star, when hunting for supernovae you're going to be exploring distant galaxies so a slightly different technique is used. When searching for supernovae, the galaxies in which you search need to be chosen according to their distance. A common mistake when hunting supernovae is to choose galaxies according to their brightness and thereby assume the brightest galaxies are the closest galaxies. While this can be correct in many cases, there are many near-by, less luminous galaxies as well as distant, bright galaxies.

Another concern for supernova hunters is that galaxies need to be chosen according to their type. Referring backing to Chapter 5 you'll recall that type I supernovae require a white dwarf with a companion star. Because white dwarfs are old stars you can deduce that type I supernovae appear only in the older star populations, for example within the central bulge of a spiral galaxy and of course within the old star populations of elliptical galaxies. However, type II supernovae are the result of massive, quickly evolving young stars and therefore appear only within galaxies where stellar formation is still underway, for example the younger spiral galaxies.

When conducting a supernova hunt, some homework is needed before beginning. A little research will maximize your search method and improve your chances of discovering one of these rare events.

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