Our Sun is a typical G2 star, about 4.5 billion years old, a yellow dwarf star that occupies a region of the Orion spur, that extends outwards from the Sagittarius arm of the milky way galaxy, our home galaxy. Our sun has lived less than half its lifetime and will last for about another 5 billion years before it becomes a white dwarf star.
Our sun goes in an orbit around the center of the galaxy, bringing with it all the planets, moons, comets, asteroids and debris of its own system, taking about 230 million years to make one trip around the galaxy.
When you look at this image, you can get a rough idea where our sun is located in the galaxy, a galaxy that contains roughly 100 to 400 billion stars and is about 100,000 light years across. Just examining the numbers makes our home a rather anonymous place in the universe, in fact, it is pretty average and pretty boring.
And yet on this tiny blue dot, where we live in this boring place in the life zone of this average star located in a pretty typical galaxy sits all that we know and love. This special place with an atmosphere capable of containing us, and biodiversity galore, all the things of life and everything we know. Just to realize how average we truly are in it all yet how special life is, I think, holds a special meaning in the quest of understanding us.
If you want to get a better idea of where we sit in the galactic neighborhood, the graphic shown below provides a more detailed map. I think the essence of it all really begs us to answer one basic question. Are we alone? I don't see how we can be.
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