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Getting to grips with it all.

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Being completely new to astronomy, reading the science threads on the forum has really inspired me to understand exactly 'what' I'm looking at in the night sky. Now..I'm no scientist, with only a basic understanding of physics, but I'm slowly coming to grips with 'the big bang', star formation, the speed of light, etc...but have found that theories relating to gravity/ relativity have left me exasperated and deflated. (This stuff just really isn't sinking in!!!):)

After a particularly long session of reading, trying to get to grips with gravity, I gave up, and gave myself a break visiting the hubblesite, to gorge on some stunning astropics, and came across their article on 'Dark energy'. Well...I had an idea of 'dark matter', but 'dark energy' was new to me, and it completely blew me away that, 74% of the universe is made up of this stuff, that no-one can quite explain!!!....YET!!:D

And you know?...I feel a whole lot better now! The universe still remains a mystery...and not just to me!!:)

I know I've got a lot to learn, but I'm not gonna beat myself up about it! It'll come I guess..in time, but for now, I think I'll just stick to the basics, and just enjoy 'looking up'.


P.S Any suggestions of reading matter along the lines of 'Relativity for Dummies', greatly received.


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John Gribbin writes well for the general reader. Just read all you can on relativity and gradually you get a feeling for it.

You know that shortly after Einstein's publication a journalist asked Sir Arthur Eddington if it was true that only three people in the world understood it. Eddington stroked his chin for a moment and said, 'Hmmm... I'm trying to think who the other one might be...'

You are not alone.


Edited by ollypenrice
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It is an abstract concept, imagine space is a stretched out bed sheet you drop a weighty object onto it it produces a curve in the space (bed sheet) around that ojbect. Now if you drop another you'll noticed the curve that produced in space by the large weighty object drawing the smaller object closer, this is not gravity pulling the smaller object in (Pulling is too direct to describe this), its the indirect effect of large object has on the space and the second object simple finds its easiest path within the curved space, so instead of imaging the object being pulled it, its simply settling into a warped path of space which has been created by a larger object.

Just like most analogies they should not be pushed word for word, just simply a method of clearing your mind when thinking of seemingly mind boggling ideas :grin:

Hope it makes sense to you :)

EDIT: Also you mention the Dark Matter and energy, well, Dark matter is the seemingly invisibile mass in our universe, almost a opposite of mass. Dark energy is like the anti gravity of the universe, seemingly behind expansion.

The fact we are made pretty much of nothing is to do with the size of the space inside an atom, it is virtually an empty shell, to put it into perspective, if you took all the empty space out of all the people in the world (Don't ask how we would do this B)) and then put the actual matter together, we'd all make a sugar cube sized lump. This sound ridiculous, but as soon as you come to terms with this idea, you realise that the universe is not much different even with huge galaxies, stars and spanning Nebulae!

Edited by Karlos
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Many thank Karlos for posting that quite 'visual' analogy. That has really helped, and it does make more sense to me!!:)

I was struggling with the concept of objects falling through space...that things are not 'static', but in motion. Your explanation makes this easier to comprehend, especially in terms of gravity - that objects don't get pulled together by gravity, but by the effect their mass has on the space around them, which then effects the movement/path other objects take in the curved space created.

I think I'm finally getting the basics!!....phew!! (My head hurts!)

I really appreciate your time, trying to make these concepts a little simpler to understand for a very non-scientific newbie like me!!

wishing you clear skies,


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more than 80% of all the discoveries and knowledge we have of the Universe came from spectroscopes..

mhhh....spectroscopy. Yet another area of astrophysics to get 'to grips' with!! :)

I find it amazing that, by examining an objects 'light', it's possible to determine distance, size, and even what elements the object is made of! And I find it quite beautiful that elements have their own unique 'colours' that can be seen and recognised.

I very much doubt, with my own limited science background, that Spectroscopy will become much more in-depth for me than the simple understanding noted above, but I am quite in awe of, and admire those in the field who are able to enhance all our understanding of the universe, by seeing, (and understanding!) the light!!

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It's even more amazing when you consider you can do all that with a very simple grating (like the star analyser) on your very own telescope! No problems with light pollution in spectroscopy! A very underrated avenue of amateur astronomy. Well worth while.

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