Re: [ATM] Sidewalk or Grass walk rookie observer's

["Vladimir Galogaza" <vladimir.galogaza1@zg.t-com.hr>]

John,

>Ya, I hate the one, "how far can you see?"

I remember fanfare when Hubble space telescope was built.
It was said how much further it will see in our past because of
its light collection capability.

I see no reason why the how-far-can-you-see question has
 so bad reputation. To me it is legitimate and on a point.
Since photon flux is inversely proportional to the square of
distance to the source and directly on collecting area
bigger scope will see further because light detector has
finite sensitivity (threshold) or photon efficiency and signal to noise
ratio.
It is known that we can see up to 6th magnitude with
naked eye. If we can see more by binoculars it is because
of larger light collecting area bringing more photons to retina
exciding sensitivity threshold and noise. Wee can see fainter sources 
and/or
FURTHER.

If somebody is yelling from 100m distance you will hear it,
if from 1 km you won't. If instead of the ear you use
trumpet like collector  "how far can you hear" with it
is not wrong question.

I never gave street telescope presentation. But if my reasoning
is not wrong, I will take care to answer "how far" question.
So what is wrong with this reasoning?
Please tell me before I start street lecturing.



Regards
Vladimir



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