Posts Tagged ‘Hubble’
Science, the limits of human knowledge, atheism, and religion. Part I.
Yes, this is the post where I explain everything. That was a joke. I explain almost everything in this post. Of course dogs are mammals, that was a joke too. OK, this is an extemporaneous post because I had a thought. And like all good bloggers, when I have a thought, my second thought is, can I make a blog post about this thought? In this instance, the answer is yes. Because this thought is a thought that I want feedback on. Yes, gentle readers, I am using your brains to hone my thinking. Probably best not to even try and visualize that.
Moving right along, the above is an image of the Hubble Ultra Deep Field. This is an area of the sky about a tenth the diameter of the full Moon. Astronomers picked a spot with little dust or nearby stars to obscure the view. There actually aren’t too many spots like this in the sky, we really are stuck in a hazy section of a galaxy. It could be worse, though it could be a lot better. That’s the topic for a future post, but I digress. It took the Hubble nearly four months to take this image, it’s the “deepest” image ever taken, showing galaxies that existed about 13 billion years ago, just hundreds of millions of years after the Big Bang. If one tries to think about the time scales in this image, or the number of stars and planets involved, it’s more or less incomprehensible. At the time of most of the galaxies in this image, Earth and the Sun itself were just atoms scattered over a vast expanse of space, or in stars yet to spew them into space in supernovas. Earth wasn’t even a twinkle in the Universe’s eye when some of these galaxies in this image existed. Our galaxy itself, the Milky Way, didn’t even exist at the time of the furthest galaxies in this image.
So it’s safe to say that this is a data rich image. Astronomers will be studying it for decades. And building instruments to peer even more closely into the Universe, the Hubble II is in the works. And this is just one photograph, albeit a very special one. I could, if I wanted to, list vast numbers of other “data collections,” for want of a better word, that will keep scientists busy for decades. There’s still data being mined out of the Moon rocks and Russian probes to Venus decades ago. In fact it would be safe to say that the data from the majority of space probes has yet to be fully analyzed. In a lot of cases new technology makes it possible to reanalyze old data, and all the while new data is being added at an increasing rate as newer probes get ever more sophisticated. In other words, despite their ever increasing understanding of the Universe, in a very real sense astronomers are losing ground in that the amount of data to be analyzed is ever growing larger.
And this is just one human field of scientific endeavour. Granted, it may be an extreme example of this, but the same thing is most definitely happening in other fields of inquiry. Museums around the world are filled with artifacts and biological samples that have yet to be analyzed. In fact new discoveries are made regularly by studying stuff in museum drawers. In physics, every time they build a bigger collider, they get results they didn’t expect. And have to build a bigger collider to understand them. New frontiers in archaeology and paleontology open all the time. Otzi is but one dead man, and new stuff is still being learned about him and his times decades after his discovery. Heck, a single finger bone in a cave in Asia recently revealed a hitherto completely unknown human-like species.
My point here, the first one at least, is that while human and scientific understanding of the Universe is growing every day, the body of unknown knowledge is keeping pace or even growing faster. Everywhere we look in the Universe around us, there appear to be layers of complexity that never end, new discoveries always reveal new unknowns. Or in another way of looking at it, as the body of human knowledge grows, the boundary between what we know and don’t know gets larger! In other words, there will always be stuff for scientists to investigate, at this point it is clear that Victorian conceits about science understanding everything were childishly optimistic at best. The Universe is so complicated and so vast on so many levels that it’s safe to say that humans in the foreseeable future won’t even come close to understanding it all.
In other words, the scientific understanding of the Universe is that we will never fully understand the Universe. It’s too large, it’s too complicated, and there are very finite limits to what humans can accomplish. The Universe is greater, older, bigger, and more complex than humans can really grasp. And to me that’s just amazing. As J.B.S. Haldane put it: “My own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose.” No matter how much human’s understand, there will always be new mysteries and new frontiers to explore. At least in the foreseeable future.
What does this have to do with atheism, religion, and my as yet unmentioned blog post inspiring thought? That’s part II, coming tomorrow.
Part II is here: Science, the limits of human knowledge, atheism, and religion. Part II.
(The above image was taken by NASA and is being used legally within their guidelines. NASA does not endorse Doug’s Darkworld. Hell, NASA is likely completely unaware of Doug’s Darkworld. Probably for the best, they have better things to do.)
Ira’s Ghost, Another Space Mystery …
Ever since my “Hanny’s Voorwerp” post I’ve had my eye open for more cosmic mysteries. There’s a fair number of them actually, I also covered the Axis of Evil and Dark Flow as well. And there’s many more to be found no doubt. The Universe is a big place, and the Hubble Telescope has only examined a tiny tiny amount of it in detail. Just like in any photography, long exposures are needed to take pictures of very faint objects, and some of the things Hubble has photographed are very far away dim objects indeed. Then when one realizes that visible light is just a tiny part of the picture, and, well, we will be finding new things in the Universe for decades or centuries to come. Yes, an age of exploration that will last for centuries at the very least, and forever if we start to venture forth among the stars. In fact we better venture forth to the stars or we face extinction according to Steven Hawking. Of course he previously warned us about the dangers of running into hostile aliens, so if I understand this right, according to Steven Hawking, we’re damned if we do and damned if we don’t. I don’t like the sound of that at all.
Moving right along, Ira’s Ghost. (nebula IRAS 05437+2502) Imaged above, a refection nebula in the constellation Taurus. I’m not sure exactly how far away it is, but it is inside our galaxy. It’s a very small faint nebula, and only got photographed because it got lucky, there was some spare time on the Hubble and this was on the list of “bonus” targets. A nebula means it’s a cloud of gas, and a reflection nebula means it is lit up by some external source of light. This is opposed to an emission nebula that is glowing of its own accord. It may look like thick gas too, but in actuality it’s not. The gas in a typical nebula is about 100 to 10,000 particles per cubic centimetre. The Earth’s atmosphere contains 2.5 × 1019 particles per cubic centimetre. In other words we call it a gas, but for all practical purposes a nebula is just a slightly dirty vacuum. Granted brand new planetary nebulae have higher densities, but still nowhere near the density of gas in Earth’s atmosphere. Still this is the stuff from which stars were made, in fact every atom in our bodies was once part of nebula in space billions of years ago. Yes, we’ve all been galactic tourists so to speak. Maybe that’s behind our drive to explore space … we’re homesick on an atomic level.
So what’s the mystery? It’s just a pile of dust in space glowing by reflected light. There’s thousands of reflection nebula in the galaxy, why is this one mysterious? It’s mysterious because we don’t know what is illuminating this dust! The bright arc near the top is especially mysterious, there should be a bright star (or something!) nearby lighting it up … but there isn’t. Kinda like the situation with the aforementioned Hanny’s Voorwerp, though that’s a vastly larger object.
Fortunately scientists have a theory. They’re good that way, scientists are always coming up with a helpful theory. In this case scientists hypothesize that there was a massive star lighting up the nebula that somehow attained a high velocity and left the nebula. Brilliant. OK, I’m being unfair here for artistic licence. It is however both a singularly obvious theory … and one that poses as many questions as it answers. Theories like that are a good place to start, but not really bringing us any closer to a solution. Will scientists ever solve this mystery? Maybe. As astronomical mysteries go though, this one is kind of unimportant in the greater scheme of things. Solving it would likely require more Hubble time, and the Hubble is booked solid so to speak.
No real lessons or insight here. Just one of many examples that there’s all sorts of stuff out there that we don’t understand. And likely always will be, one of the things that gets me most excited about space exploration is that we are always finding things that no one ever dreamt of. One looks back at humanity’s SciFi the truth of it is, it’s been pretty unimaginative when it comes right down to it. Simply humans projecting their own selves and viewpoints on the Universe. Like say a recently very popular movie involving smurfs on steroids. A Bat Durston if there ever was was.
(I believe the image above is Public Domain under all sorts of copyright laws as it it was put together by a variety of government agencies. And it’s not being used for profit or to endorse any product. Credit: ESA, Hubble, R. Sahai (JPL), NASA My next post is going to be about another space mystery, or very bad things in Afghanistan. Reader’s choice.)
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