The Powerful Supernovas

Generally, supernovae in other galaxies cannot be predicted with enough accuracy. Many amateur astronomers however, greatly contributed to the finding of supernovae through optical telescopes. Both professional and amateur astronomers hunt down these celestial events since they are very rare.

Causality

Currently, there are only two known factors that cause a star to go supernova. The first one happens when a star is at least five times more massive than our Sun. Massive stars usually burn huge amounts of nuclear fuel at their cores and produce a lot of energy and thus their center is very hot.

This heat generates pressure and it is because of this pressure a star’s nuclear burning keeps it from collapsing. Stars are balanced by two opposing forces. The gravity of the star is trying to squeeze it into the smallest, tightest ball possible while the nuclear fuel burning in the core creates a strong outward pressure. Thus, it resists the inward squeeze of gravity.

However, stars run out of fuel in time and cool off. As they cool off, pressure also decreases. Because of this, gravity is now able to do its thing and the star collapses. This collapse happens very quickly that it creates enormous shock waves that cause the outer part of the star to explode.

Often, a very dense core is left behind along with an expanding cloud of hot gas called a nebula. Some supernovas that occur within stars around 10 times the mass of our Sun may leave behind black holes – the densest objects in the universe.

The second type of supernova can happen in systems where two stars orbit one another, a binary star. This happens when at least one of those stars is an Earth-sized white dwarf. A white dwarf is a star similar to our sun that ran out of fuel. If one such star collides with another or pulls too much matter from it, the white dwarf star can go supernova.

The Future – Milky Way Candidates

Many stars quite close to Earth are likely candidates of going supernova. Stars such as Antares or Betelgeuse are expected to go supernova at any moment and the recent behavior of Betelgeuse – it became very dim – suggests that it may indeed be the next star in our galaxy that goes supernova.

Both amateur and professional astronomers are constantly observing the sky in the hopes of catching the first phases of such an event. Though these stars are relatively close to us, it is unlikely that their explosion will have a major impact on us.

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