Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 14/09/2010 18:06:07

Title: If Earth was made of glass, would we be able to see through it?
Post by: thedoc on 14/09/2010 18:06:07: If the world was made of glass, would we be able to see through it?
Asked by John

Go to the show page. (http://www.thenakedscientists.com/HTML/podcasts/show/2010.09.12/)

[chapter podcast=2816 track=10.09.12/Naked_Scientists_Show_10.09.12_7125.mp3](https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.thenakedscientists.com%2FHTML%2Ftypo3conf%2Fext%2Fnaksci_podcast%2Fgnome-settings-sound.gif&hash=f2b0d108dc173aeaa367f8db2e2171bd) or Listen to the Answer[/chapter] or [download as MP3] (http://nakeddiscovery.com/downloads/split_individual/10.09.12/Naked_Scientists_Show_10.09.12_7125.mp3)
Title: Re: If Earth was made of glass, would we be able to see through it?
Post by: thedoc on 14/09/2010 18:06:07: Dave - Glass is obviously transparent, so if the world was a beautiful pane of glass, you could see straight through it. But if you've ever dropped a glass on the floor, it shatters into thousands of pieces. If you've got loads of little pieces of glass, it stops being transparent. although each piece of glass is transparent, because when light hits a surface, some reflects and some refracts (it bends), if you have a pile of rough bits of glass, you get lots of reflections and refractions and the light all merges together into a white blur. This is why ground glass always looks white.
Chris - That's the same reason why snow looks white when water is transparent isnt' it?
Dave - Yes, and the same with sugar - each crystal is transparent, but a bowl of sugar looks white. So because the Earth isn't nice and flat and shiny like a pane of glass, if it was made out of glass it would probably look white.
Title: Re: If Earth was made of glass, would we be able to see through it?
Post by: kenhikage on 16/09/2010 13:53:02: Even besides the tiny bits, I'd think I'd think a lot of the large chunks would look more like quartz than the man-made glass we're used to. That is, we'd see colour (assuming there are coloured objects) through it, but not well defined shapes.

The impact on subterranean and cave life would be interesting to see. As would a volcano. [|)]
Title: If Earth was made of glass, would we be able to see through it?
Post by: lightarrow on 16/09/2010 21:32:36: Another big problem would be trasmissivity: common glass has a transmission coefficient of ~ 92%. After some tens of metres you don't see anything anylonger.
Title: If Earth was made of glass, would we be able to see through it?
Post by: Raghavendra on 20/09/2010 07:44:59: "If our world would made of glass"

Cosmic rays wouldn't have existed!! And we would not have born at all.

Imagination has no end!
Title: If Earth was made of glass, would we be able to see through it?
Post by: Bored chemist on 20/09/2010 08:39:15: Even pure silica has an attenuation of 0.03dB/Km (wavelength unspecified but probably in the near IR) so the thickness of the earth would reduce the intensity of the light by about 10^38 fold. It would be opaque for all practical purposes.
Title: If Earth was made of glass, would we be able to see through it?
Post by: lightarrow on 20/09/2010 12:18:34: Quote from: Bored chemist on 20/09/2010 08:39:15
Even pure silica has an attenuation of 0.03dB/Km (wavelength unspecified but probably in the near IR) so the thickness of the earth would reduce the intensity of the light by about 10^38 fold. It would be opaque for all practical purposes.

It's even worse, in the visible range attenuation is ~ 10dB/Km:

http://en.wikipedia.org/wiki/File:Zblan_transmit.jpg
Title: If Earth was made of glass, would we be able to see through it?
Post by: thedoc on 10/12/2010 15:32:56: We discussed this question on our show
Dave - Glass is obviously transparent, so if the world was a beautiful pane of glass, you could see straight through it. But if you've ever dropped a glass on the floor, it shatters into thousands of pieces. If you've got loads of little pieces of glass, it stops being transparent. although each piece of glass is transparent, because when light hits a surface, some reflects and some refracts (it bends), if you have a pile of rough bits of glass, you get lots of reflections and refractions and the light all merges together into a white blur. This is why ground glass always looks white.
Chris - That's the same reason why snow looks white when water is transparent isnt' it?
Dave - Yes, and the same with sugar - each crystal is transparent, but a bowl of sugar looks white. So because the Earth isn't nice and flat and shiny like a pane of glass,if it was made out of glass it would probably look white.
Click to visit the show page for the podcast in which this question is answered. (http://www.thenakedscientists.com/HTML/podcasts/show/2010.09.12/) Alternatively, [chapter podcast=2816 track=10.09.12/Naked_Scientists_Show_10.09.12_7125.mp3](https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.thenakedscientists.com%2FHTML%2Ftypo3conf%2Fext%2Fnaksci_podcast%2Fgnome-settings-sound.gif&hash=f2b0d108dc173aeaa367f8db2e2171bd) listen to the answer now[/chapter] or [download as MP3] (http://nakeddiscovery.com/downloads/split_individual/10.09.12/Naked_Scientists_Show_10.09.12_7125.mp3)
Title: If Earth was made of glass, would we be able to see through it?
Post by: Bill S on 10/12/2010 16:20:07: If the Earth were made of glass, the most likely form would be that of the naturally occurring glass, obsidian, which is not transparent, except in very thin sections.
Title: If Earth was made of glass, would we be able to see through it?
Post by: maffsolo on 10/12/2010 17:48:59: If you are referring that the World as a material object as a physical lump of polished glass, called earth, it would be shaped like an orb a crystal ball of sorts.. Looking through it would optically invert and fatten the image, (optical term for wide angle imaging panning 360 deg plane), being focused on the other side. Difficult to break, but once broken the Fragments would need to be looked at different angles to see clarity. Maybe multiple of the same images, maybe nothing until moved around.

Now if it is a metaphor we are looking at, "The World of Glass", states it is very fragile society. Once disturbed will it will carry that scare for life. Then, it may heal with a faint scare that will be ignored to be disturbed again. Society can not remember any apocalyptic event, so it is said, “One who does not know their history, is doomed to repeat it.”
Title: If Earth was made of glass, would we be able to see through it?
Post by: SteveFish on 10/12/2010 18:21:03: I once owned a 2 foot square, 2 inch thick piece of glass. I couldn't see much of anything when I looked through it edgewise except a dim green image that was degraded by, presumably, the impurities that stacked up over 2 feet. It was pretty clear when looked through flatwise.
Title: If Earth was made of glass, would we be able to see through it?
Post by: Geezer on 10/12/2010 19:38:03: If earth was made of glass, would it be ground glass?

What I want to know is, if the Earth was made of chocolate pudding, would we be able to eat it?
Title: If Earth was made of glass, would we be able to see through it?
Post by: maffsolo on 10/12/2010 20:16:19: Quote from: Geezer on 10/12/2010 19:38:03
If earth was made of glass, would it be ground glass?
Beaches full! Until you reached the core, then it may less ground or smaller or a cherry.

Quote
What I want to know is, if the Earth was made of chocolate pudding, would we be able to eat it?
If you like chocolate pudding and ate the whole thing then you may discover you may be in a world of Sheet, cakes.