Many people are under the illusion that Earth is the only place in the universe that is active. In fact few people take the time to recognize just how amazing our cosmic neigborhood is. From nebulae creating new stars to the explosion of a supernova, our local area in the universe is teeming with activity.
Gas, plasma, and dust from collisions or explosions in our galaxy create gas clouds that, many times collapse and form new stars. In one senario, several masses of these clouds collided with one another. Some of the clouds combined while others were booted into deeper space. For exampe, one gas cloud, classified as the Smith Cloud, was repelled so far that it almost left our galaxy. Due to the massive influece of the Milky Way’s gravity, though, it has now turned so that it is barreling toward our disk of the galaxy. This expanse of gas spanning over 11,000 light years is traveling at great speeds to collide with the Milky Way. Scientists has estimated that the collision will take place in about 27 million years (a very short time in the cosmic perspective). Such an impact is estimated to give birth to over 2 million new stars! But as the universe stays in equilibrium, new stars are born and old stars die off.
One of the closest supernovas was at a distnce of about 12 million light years, but could one have been closer in the past? German scientists found a rare isotope of iron-60 in 1999, but since this isotope is created only in supernova explosions, Earth must have been close enough to receive some of the debris. If so, the supernova would have been placed within 325 light years of our planet. Scientists are also looking into “orphan” stars and matter that exist in distant, intergalactic space. Unfortunetly, in order to do so, we must look past our local neighborhood into deeper space where our technology’s sight is limited. Thus, astronomers look to supernova in the area. By being able to see the bright explosions, we can put conclusions together about the matter deeper in the universe. Researchers from the University of California Berkeley have analyzed the most recent supernovae and have concluded that 11% of supernovae occur in intergalactic space. From this statistic, and the fact that matter (stars, dust, and planets) coincides with supernovae, we can conclude that 11% of matter exists between galxies. It is amazing that we can come to this conclusion about ejected material like the Smith Cloud without even having the tecnology to see that far.
More intersting phenomina are taking place within our local neighborhood in the universe, but few people are lucky enough to dwell in its awe inspiring beauty. Next week we will look further into our neighborhood and its contents including a supermassive black hole that could possibly be supporting life.