Eta Carinae III
There’s little doubt that the larger star in the system known as Eta Carinae will soon expire — and in spectacular fashion. But just how spectacular remains uncertain.
Eta Carinae consists of two stars. The larger of them is perhaps a hundred times as massive as the Sun or more. Such a monster burns through the nuclear fuel in its core at a tremendous rate, so it lives for only a few million years.
When the core can no longer produce energy, the star will stage a spectacular explosion. In fact, it may be the most powerful type of blast of all — a gamma-ray burst.
In this scenario, the core would collapse to form a black hole. The gas just outside the core would then fall toward the black hole. The gas would generate beams of gamma rays that would blast out along the star’s poles. The beams would last just half a minute or so, but in that time the dying star would emit as much energy as the Sun will produce in its entire lifetime.
Such gamma-ray beams are like cosmic super-weapons, blasting anything in their path. Earth doesn’t line up along that path, which is lucky for us — the gamma rays likely would be powerful enough to sterilize the side of the planet facing the beam, and could lead to mass extinctions across the entire planet.
As the gamma rays abate, the star probably would explode as a supernova — adding to the fireworks from the death of one of the galaxy’s most impressive stars.
Script by Damond Benningfield, Copyright 2014
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