posted on Jul, 18 2013 @ 12:16 PM
reply to post by network dude
You do realise the technology has altered and the old photographic technology was chemical based right so was prone to deteriorate over time, also
the very atmosphere of this planet HAS chemically altered due to different parts of the world rushing to industrialise and modernise mainly china and
the coal they burn is heavy in sulphur and other compounds, deforestation and massive forest fires as well as global pollution of other types, the
CFC's we banned will take decades or even century's to leave the atmosphere, also there has been a record of temperature rise on all planets that
NASA has monitored, the sun goes through cycles and it's spectral output may vary slightly from time to time we just don't know.
The water table is polluted with chemicals that cause birth defects and androgenise mammal and reptile species, we even splash chemical cocktails on
our skin believing it makes us more attractive to the opposite sex.
So you were saying can it be proved, son the world I was born in was less polluted than this one and guess what it is the same world so yes it can be
If you are looking for spectral analysis of the atmosphere and the sun over the past thirty years taken from various locations around the world well
I know of know such undertaking, which is not to say there is none but that I for one do not know of any and any spectral analysis would likely have
been taken at high altitude for other purposes so would be useless as the thinner atmosphere would only provide limited DATA.