On the Death of a Star

The world is a dangerous place.

Yesterday I read a story about an astronomical object located some 250 million light years from us in an obscure galaxy far far away. This object would hardly be worth mentioning being that there are so many other more colossal objects out there in space, but on this occasion this unusual star managed to make the evening news on a little far off planet called Earth, and so it bears mentioning.

Apparently this star was in it’s dying stages when it exploded into a fireball so colossal that it is estimated to have put out the equivalent of 50 billion suns for some seventy days, the duration being far longer than any other recorded supernova, and yet another attestment to the incredible power behind this unusual stellar explosion. The explosion was designated as SN2006gy, and may be what is called a Hypernova, which is an unusually violent Supernova.

This star exploded with a force far greater than what scientists had ever assumed was possible. In fact so violent was this explosion that it actually outshone the entire galaxy in which it was located! Never had astronomers encountered an explosion of this magnitude before, save but in theoretical proposals..

Yet, there was more to the story than just the magnitude, or duration of the humumgous extra-galactic explosion. It turns out that the object located at the center of the explosion is very similar to one that astronomers have observed many times before, and which happens to be much closer to our own home star. The massive, incredibly bright object that exploded with the force of fifty billion suns in that galaxy so far away that the light of the explosion actually took 250 million years to reach us, just so happens to be very similar to an unstable, and hugely massive, downright angry, violent star located here, in our very own galaxy, that goes by the surly, and somewhat ugly, name of Eta Carinae.

This star, Eta Carinae, is also at the last stages of its life, and this last stage is hellishly violent, to say the least. It is remarkable, I think to say that such things as stars should ever die, for all our existence we thought ( until very recently) that they were immortal; but though they die, let it be known, they do not die with a whimper, that’s for sure; especially not monsters like Eta Carinae. At this moment, Eta Carinae is the brightest star in the Milky Way galaxy(our home galaxy), and it is giving off the equivalent of some five million suns of energy every second! Yet for all it’s fire, and all it’s violence, scientists are fairly certain that Eta Carinae is about to die in a gigantic unimaginable explosion, and now, it is quite possible that Eta Carinae will not go like a supernova as once thought, but rather it will explode with the same order of force as did that far away star located in that far away galaxy.

Untill now scientists were sure that Eta Carinae, even if it did explode as a supernova, and even if supernova explosions are really incomprehensible to human beings, the impact on Earth was not likely to be a problem, no matter how violent the explosion should be since it was assumed that it would give off the energy of a ordinary supernova and that it was too far away to pose a real threat to our planet. But after seeing the catastrophic consequences of Sn2006gy it is reasonable to assume that there is some more calculation to be done. True Eta Carinae is very far away. Seven thousand light years is far away to be certain. So far away that light itself must travel seven thousand years to reach us from that distance(a light year is approximately five trillion miles.) If it were a normal supernova there really would be little to worry about. But fifty billion suns even at seven thousand light years is still an imposing amount of energy.

Though we cannot be certain about the amount of energy that will be released and how much of it will travel through the galaxy, it is certain that we will experience that light burst that sets the star on fire(speaking metaphorically of course.) The question is how much light is that going to be, and is there cause for concern? There is also a phenomenon associated with Hypernova’s that we should consider which is what astrophysicists term as Gamma Ray Bursts, which are etremely energetic gamma ray radiation bursts that are strong enough to end life on Earth. We do not know that GRB’s are associated with the sn2006gy event, but there is some concern about Eta Carianae.

If we were at the center of the Galaxy, some thirty thousand light years from the core, it is very unlikely that conditions would be stable enough to support life on Earth. In reality Eta Carinae for a brief period, actually will unleash the energy equivalent of what might exist at the center of the Milky way. That’s an awful lot of light and energy.

Besides that, we really cannot be certain what else might come our way. I personally do not think that the explosion of Eta Carinae necessarily spells severe trouble, but I also say that we don’t really know enough to be certain that it will not challenge us. This object, once it explodes will be quite large, and quite bright. We would probably be able to see it in the daylight. More so it will likely have a very large diameter in the sky, and it will emit monstrous amounts of radiation. Certainly satellites could be affected, as well as the astronauts on board the space station. Could it even contribute heat energy to our planet that might be significant?

Though most of the energy released is likely to be in high energy radiation like ultra-violet, X-Ray, and especially gamma rays(which could be deadly if not for the ozone layer), I am sure that tremendous amounts of the energy released will be of the infrared variety(infrared radiation is common heat energy) and so we may expect some warming with the explosion. Though I am not a physicist and could not with confidence say what kind of energy output we should expect here on earth, I do not believe that this event is necessarily going to be insignificant. An explosion of these proportions could pose significant risks. Once again what we dont know is of some concern. There is also one more possibility which might be a point of interest.

What about gravity waves? Though such waves have never been detected, it is true that when so massive an object is ripped apart with such incomprehensible violence as the death of Eta Carinae promises to be, will that not create a gravity wave? Einstein predicted that it would. How energetic might that wave be? Is that something to be concerned about? I know that gravity waves are still in the realm of theory, but they seem plausible, and in the case of Eta Carinae huge amounts of matter may reach velocities close to light speed which would be required to generate gravity waves(assuming our theories of physics are actually valid.) The reason we may not have detected gravity waves so far is that they may travel in packets and so may be quite rare. After all we have known about them as a theoretical possibility for less than one hundred years.

Our solar system is actually in a state of a most delicate balance. What would happen if that balance were to be disturbed-if even a little? Some have speculated that a minor gravitational disturbance that occurs every sixty million years while travelling through the plane of the Milky Way, may be responsible for corresponding mass extinctions here on earth. For example sixty five million years ago the Dinosaurs are thought to have been terminated because of an Asteroid that might have been dislodged from the depths of the solar system due to that gravitational effects of traveling through the Milky Way’s galactic plane. Could a violent explosion like the one expected from Eta Carinae dislodge some other comet from the depths of the solar system? The sun is expected to pass through the galactic plane on December 21st, 2012, a date that the Mayan’s believed to be the end of the world. The North American native people’s also have some myths concerning a major disaster sometime in the next decade. Could Eta Carinae aggravate some of those anxieties? True this is not scientific, yet there is a kind of psychological foreboding that seems to have become world wide(aggravated no doubt by Global Warming, the wars in Iraq, Afghanistan, and the terrorist attacks) and the general trend seems to continue with the possibility for a deadly disturbance from the depths of space.

True the distance from Eta Carinae is enormous ,and that distance will negate most of the potentially dangerous effects, but an explosion of the magnitude that we observed with sn2006gy is so massive, and so physically disruptive that there is likely to be more than just some fire works for astronomers to revel in. In fact the death of Eta Carinae is likely to be an event that will challenge the boundaries of knowledge that Astrophysicists now claim as their own. Once again it’s not so much what we know that can hurt us, but perhaps what we dont know.

All in all there are lots of issues that need to be resolved so that we can all sleep better at nights. One of these may be a dying massive star by the name of Eta Carinae which could explode at any second,or not in ten thousand years. If there is really something to worry about, I think we should know about it, and if there are any dark areas of our knowledge concerning such phenomena, we should keep in mind that it is always better to be safe than sorry. We do not want to get caught unawares in the unravelling of a potentially devastating phenomenon. Death is sometimes contageous. We often mourn when a fellow human being has met an end, sometimes when we hardly knew the person at all in life. We should not be so willing to dismiss the death of a star as personally unimportant, for if we do, we may find that we were wrong to do so.

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