Planetary Nebulas - Beauty in Space - The Last Gasps then Death of a Star
I am amazed at the images that the Hubble Telescope has been able to capture for us. I think it is absolutely fascinating to learn more about our universe and what is out in space that we can observe. Planetary nebulas are amazing things to observe, and I recall first seeming surprised that they were actually the death of a star. This seems so odd, that some of the most magnificent colors and light and energy that we can observe are the dying then death of a star. Its more amazing still, than the most glorious sunset or firework demonstration that I have ever seen.
So what is happening when we observe the light and color of a planetary nebula?
Backing up a bit, we must look at how helium fuses in the core of a red giant, which is a star in the later phases of its life. Many scientists say that helium fuses in the core of one of these red giants for about two billion years (though to be fair, I am not completely aware of how they come to those conclusions, and know they have their reasons, based on on what they do know). After enough time passes, this helium "runs out." Carbon and oxygen have been produced as well, along the way. The right temperatures are never reached however, for the carbon and oxygen to do anything really. If it were a star like our sun for instance, it would mark the end of that star's ability to create any more energy. Its a sad thing to consider the death of such a star (to me anyway), as when it creates no more energy, it is close to death.
What is happening when a star is actually dying?
I hate to talk about the death of a star like this for some reason, but this is what is happening and I am glad that it makes such a "show" because after who knows if mankind would ever have known of it? Think of all the ones we have missed.
Anyway, in the very core of the star there is a succession of "death rattles" you could say, that actually ejects matter into the surrounding space from the red giants outer layers. When this is happening, the matter can mover up to about twenty miles per second. It kind of gives off waves of matter, and it expands outward. This is what we are seeing in the pictures. The light we are seeing is from x rays and radiation (ultraviolet) that comes pouring out, and this mixes with the surrounding gas. This is when the colors seems to explode so that we can see it with the amazing telescopic images. Wow, isn't that amazing? These are called planetary nebulas. I think they are some of the most beautiful things ever seen in the heavens to date.
There is nothing having to do with planets, and they were named as they were by an 18th century English astronomer William Herschel. Back in his day, they looked to him and others like the disks from planets.
Forms of Planetary Nebulas
Some planetary nebulas look like spherical bubbles, some a single bubble, and some with multiple. Some seems to have rings, and they glow beautifully. Some of the ones I have seen are The Cat's Eye, The Eskimo, Southern Ring, The Egg Nebula, and The Butterfly Nebula, one of my personal favorite. Its wild to consider what is actually being seen at the point we can see it, versus actual time, and adding the speed of light, etc. It just literally boggles the mind.
My final thoughts
All I know, is that I am ever thankful for our own Planet Earth and our Sun, and all the anthropic constants involved that make life possible. That is actually even more mind boggling. We have so much life and to add to that the awareness of our lives and the ability to ponder it all at all. Its rather an amazing universe that we call our home.
I am prompted to add also, that I am passing along current understandings of science as it has come to me. I am not stating what I am above with 100% absolute certainty because we haven't been around long enough to observe it. I know they are going off of what they know, and how they understand matter, energy and gasses generally "behave" in space. I am still at the mercy of scientists like the Hubble Team and Nasa, and they know a bit more about all these things than I do! I am very grateful to have access to such distant happenings at all, they are amazing!