[Laser] Re: street light EME-update

[Art]

I have several comments regarding this and a few questions..........

If high pressure sodium lamps have any red or near IR lines, these 
would be the lines to look for with a ground based telescope. While 
they will still exist to some extent from scatter due to the Earth's 
own atmosphere, the ratio of scattered (local) photons to the number 
of EME received photons would make a red or near IR line much more 
desirable (less qrm from scattered photons from 'local' sources).

Once above the atmosphere, the ~600 nm hps lines would be the lines 
to look for.

I have learned of several high altitude balloon programs designed for 
educational purposes and (generally) sponsored by NASA. Some of these 
missions launch with highly stable gyro's for the purposes of doing 
celestial observations from the upper atmosphere. There is a 
possibility of hitching a ride on these flights, and I wonder if 
there are any scheduled to fly during the upcoming eclipses?

I also received an email from someone close to the Hubble telescope 
and they informed me the telescope has a full optical spectrum 
analyzer aboard and could make very short work of this task. They 
also informed me that the instruments aboard the Hubble are so 
sensitive that it would be absolutely destroyed if it was ever 
directed to view the moons surface or that of the Earth. But, the 
person closes by stating that observations of the Moon's surface are 
done during total eclipses and that someone might already have done 
this experiment or collected raw data that could be analyzed to 
extract the information we seek.

Does anyone have any bandpass filters for the sodium lines, 
especially the 589 nM line? I think they are probably available, but 
like so much of the parts we need, they are probably horribly expensive.

If I can find a suitable filter, I would be happy to make an attempt 
to do this from the ground with a photodiode and a 4 inch glass lens.

Regards,

Art