So I've been watching a lot of Astronomy related documentaries, and reading on the subject as well. Call it a renewed interest, as there was a time when I was totally into that kind of thing. I think until the age of 15 or 16, the heavens always amazed me. Well, it still does but however that interest died down after that age. Back then, I had a collection of newspaper articles and photos cut from newspapers or photocopied from library books. Yes dear reader, it was a time when the so called age of information was still a decade away. I did not own a computer and the Internet was only heard of. So, yes, the information was not a Google search away and come to think of it that may have been one reason my interest died down. But a few weeks ago I read this news somewhere about a new found solar system some thousands of light years away, and that sparked my interest again. Luckily, this time around I'm better equipped - the Internet is there, and you can download just about all the documentaries that there are. Thank God for the speedy Internet in Japan though. Thus I set to work; downloaded some stuff, started reading on the subject and started feeling amazed again. How can you not be? Here are some fun and amazing facts that I recently learned, or refreshed the memory of.
Our Sun is a very average star, it's about 5 billion years old and will probably live another five more. The moon was created as a result of a huge body more than half the size of our earth crashing onto the earth, at a very early stage of Solar System's life. Now, the moon's been orbiting around us since then but gradually moving away from us at a rate of 2 inches every year. And it is destined to leave us one day, once earth's gravity is no longer able to hold it. The results would be catastrophic to earth; earth's tilt of 23 degrees will be much more than that, the four seasons will be all messed up with having 6 month long winters or summers depending on which part of the globe you are in. Some species will be gone forever, our biological clocks altered, there won't be tides and it'll take some getting used to. However, luckily, the deadline is some 50 billion years away. Thank God.
Mars has the largest volcano found in the Solar System, and it also has an ice cap. There's also evidence that there once was flowing water on it, but it's all gone now. Jupiter, Saturn, Uranus and Neptune are all gas planets while some of them have bigger moons than Pluto. Speaking of which, it was demoted to Dwarf Planet because there are a couple of asteroids out there that are bigger than Pluto. Poor guy, must have hurt his feelings. Jupiter has a moon called Europa, not Europe, which has a thick crust of ice beneath which scientist believe is an ocean. One big ocean that is. And they say it is very likely there is life on it, or rather, in it. Sadly, with the current technology we have it takes six months to Mars, the closest planet, while a trip to the outer Solar System takes up decades. Planning a weekend swim in Europa's oceans is a little too early I guess.
Let's move outside our Solar System. The closes star is some 4 light years away. That's crap, so even at the speed of light which probably we will never achieve, it takes four years to get there. But hold on, if that is the closest, how far away do you think the furthest? Well it's hard to say, but estimates have been made that it's possibly 156 billion light years wide. To put that in perspective, the age of universe itself is estimated to be a little over 14 billion years according to the Big Bang Theory. I mean the real theory, not the TV show. That means if you started travelling at the speed of light since the beginning of the universe, as of today you have covered only about 10% of the width of the universe. This might seem a contradiction, because according to the Big Bang Theory, when this big bang happened, the universe was a singular point. Now if nothing can go faster than light, how come the universe itself did? Well, read on, it's explained there.
The largest star found so far is estimated to be between 1800 and 2100 solar radii (the radius of the Sun), but luckily it's 4000 light years away. Though it is a singular star just like our Sun, most of the stars out there are binary stars. Even they don't like being alone do they? Some of these massive stars, at the end of their lives may collapse onto themselves forming black holes. Now black holes are big bad guys who suck up everything that dares get too close. However, contrary to popular belief they don't go around sucking up everything in their paths. If you go near it with just the right speed and angle you can settle into an orbit around it just like you would orbit around a planet. There are some billions of black holes are out there, and you could find a super massive black hole at the center of most galaxies including our own, Milky Way. Their masses are on the order of hundreds of thousands to billions of solar masses. However, you'd be surprised to learn that they have an average density lower than that of air. Don't believe me? Go here and read then. And if there are billions of black holes in the universe, how many stars are out there do you think? Well, there are about 10 to the power of 11 or 12 stars in our galaxy alone, and there are about the same number of galaxies in the universe. So, do the math. To put this in perspective, there are more stars in the universe than there are grains of sand on earth. How's that sound?
But, the sad thing is despite knowing all this, we still have absolutely NO evidence whatsoever to say that we are not alone. Not yet at least. When you think about the size of the universe, the variety of it, everything suggests that we must not be alone. Think about it, among so many trillions of stars there should be at least a few planets that are able to support life as we know it. Of course there could be life far different from what our conception of it, but let's not go there. The universe has all the elements we have on earth in abundance. Scientists have already found a few Earth like planets and they have estimated there must be at least hundreds of thousands of such planets in our galaxy alone. So why haven't we met anyone yet? The most probable answer is that the speed of light is actually can never be broken irrespective of how advanced a species you are. It could just be the limit of transportation after all. Of course there are theories such as using wormholes for interstellar travel, so maybe we just aren't in the right place or the time yet. It is also possible that we are not really of any worth intelligence to those higher beings that are able to travel to distance stars, and that they are giving us time.
Or, simply, it could be that we truly are alone. I dearly hope though that it isn't the case.