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Huge Supernova Baffles Scientists
Iddo Genuth writes "Scientists from the Weizmann Institute of Science in Israel and San Diego State University have observed an explosion of a star 50 times larger than the sun. In what they call a 'first observation of its kind' the scientists were able to notice that most of the star's mass collapsed in on itself, resulting in a creation of a large black hole. While exploding stars, or 'supernovae,' aren't unprecedented, this star, which lay about 200 million light years away from earth and was million times brighter than the Sun, has exploded as a supernova at a much earlier date than the one predicted by astronomers."
200 million, not 200
Here's the Hubble press release and the paper.
You determine the age of a star based on several factors, but it's primarily based on the ratio of elements within the star. The life of a star is a continual struggle between the force of gravity, pulling the star inward, and the force of the fusion process taking place within the star, pushing it outward. As the fusion process continues, the hydrogen is fused into progressively heavier elements up until the point where it reaches iron. Fusing iron creates no net gain in energy, as the fusion process for iron requires more energy than is generated. By measuring the spectrum of a star, the stellar mass, ratio of elements, and other characteristics can be observed, which, coupled with existing data about stellar life cycles, and stellar classifications, can be used to determine the star's lifespan. Figuring out the lifespan of a star isn't new science, the trick here is that they believe their prior models of stellar evolution and stellar lifecycles may be incorrect. And if you actually read the article, you would understand as much because they say it in plain English toward the end.
Sorry, but most of your ideas are far off base.
One is that this was a binary system, that a second star was behind the first at the time of the "pre-supernova" photo, and that they collided. Remember, they have very few photographs, are not using any data from space telescopes like SWIFT, and are therefore filling in the blanks.
Not correct -- they used both historical Hubble data to detect the star before it exploded and followup Hubble observations to confirm that the star has now disappeared. And they have data from the Keck Observatory with observations of the supernova. That's about as good as it gets for data.
We can assume that star evolution is moderately well-understood (though not completely), so if what they think is the input is inconsistent with what they know is the output, the chances are really good that the input is wrong, especially with such little data.
Star evolution is well understood for the bulk of the lifetimes of stars like the Sun, but there are still many questions about this sort of massive star. Such stars lose most of their mass during their lifetimes through stellar winds, which are themselves very complicated and not that well understood theoretically. And then the stars go through this luminous blue variable stage (which is what this star was before it blew up), and that is very poorly understood and is the subject of a lot of current work.
So it is in fact much more likely that this has uncovered a part of late stellar evolution of massive, luminous stars that is not correctly described by current models. We don't need any really bizarre explanation like iron planets falling into the middle of the stars. (And that wouldn't work anyway -- the planet would have to have a mass bigger than the Sun to have a big effect.)
Socrates thought the earth was round.