Scale of the universe

[davedotcom]

Hmmm, just tried to have a look from my work PC (a bit naughty but it isn't 9am yet!!!) and it was blocked - categorised as 'Sex/Adult Material'!!! What kind of stuff are you boys looking at!

I'll have a look when I'm home but agree with the comments, the vastness of the universe is scary!

[Johnny Redgate]

"Space is big, really big. You just won't believe how vastly, hugely, mind bogglingly big it is. I mean, you may think its a long way down to the chemists, but that's peanuts compared to space...."
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[pressld2]

Originally Posted by Johnny Redgate

(subject to a few assumptions that probably aren't true and some unchecked maths!)

I asked my eldest if he fancied checking your maths and he said...

"A quick back of the envelope calculation (while that is a cliché, I literally did it on the back of an envelope!) gives me 2.2 x 10^151 neutrinos in the observable universe and 6.4 x 10^153 in the estimated actual universe. My assumptions (as far as I've noticed) are that all the objects are perfect spheres, which is probably not too far off in the case of the observable universe, but further off for neutrinos, and probably utter nonsense for the entire universe (the margin of error on the diameter is probably pretty huge anyway). I've also assumed that the spheres pack perfectly, which they don't (the maximum you can get is about 75% density), but the idea of worrying about the space left between the neutrinos when you squash them together seems a bit silly because you almost certainly can't do that to neutrinos anyway!"

...so it looks like your answer was a smidgen high. Of course, you may have made slightly different assumptions.

Originally Posted by davedotcom

Hmmm, just tried to have a look from my work PC (a bit naughty but it isn't 9am yet!!!) and it was blocked - categorised as 'Sex/Adult Material'!!! What kind of stuff are you boys looking at!

I couldn't look at it from work either - I got "Active content removed." Dunno where they're getting "Sex/Adult Material" from but hey, whatever floats their boat!

Dave P.

[Johnny81]

Originally Posted by pressld2

My eldest sent me this with the comment "This is VERY cool!" I have to agree...

Scale of Universe - Interactive Scale of the Universe Tool

Dave P.

This is awesome!

[nytecam]

Excellent interactive prog A bit surprised that it suggests that we [earth/solar system etc] are NOT at the centre of the universe. I'd go as far as to suggest each person is the centre of his/her universe - those to the east etc can 'see' a little further in that direction and a little less to the west and so on eg a 14BLY radius sphere surrounding each person - now where's the tape measure.

[Johnny Redgate]

Originally Posted by pressld2

...so it looks like your answer was a smidgen high. Of course, you may have made slightly different assumptions.

Dave P.

I reckon if a smidgen can be two orders of magnitude the universe really is big! I just assumed a perfect sphere for the estimated actual universe and cubes (of all things) for the neutrinos, perfectly packed together even as far as the neutrino fractions at the universe edge. Didn't want to overcomplicate, you know

[fairplay]

Imagine the size of the box it all fits into - they must have cut down a helluva lot of trees.

Neil.