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In principle you can see the galaxies down to around magnitude 12 under a dark sky (and knowing just where to look) and some of those can be 100 million light years away or more so you can do the maths ! :icon_biggrin:

 

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In stargazing the right question is not how far but how faint you can see. A 20x80 shows galaxies dozens of million light-years away, but only because a galaxy pumps out untold amounts of light. The 20x80 would also show Saturn's largest moon, but only because it's very close at only one light-hour, which compensates for the minuscule amount of light it sends us. 

The abysmal differences in true brightness and distance make the difference in apparent brightness just as abysmal, so we stick to apparent brightness.

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not how many miles but how many millions of light years.... you'll easily see the Sombraro galaxy, that's 31 million light years or approximately 183,433,572,000,000,000,000 miles.... this is the farthest one I can think of while at work that I did see through my 10x70 binoculars.

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On 10/13/2017 at 09:54, John said:

"How far" is a perfectly valid question to ask :icon_scratch:

 

Is it?. It depends on which side of the fence you sit. Is/should space be measured in "distance" or "time". A "light year" is the distance/speed that light can travel by our man-made definition of time.

Im confusing myself. LOL

When i observe, i suppose the easiest way that our brains can think is "distance".  To be correct though.............we are looking back in time.

20x80 bins are great. I have 20x90 and i can happily observe galaxies. Due to the limited magnification of bins..............you will never get the same views of the same object as with a scope. Thats ok though because bins and scopes are 2 very different things. You can certainly own both (i encourage it). 

Indeed, many objects in the night sky look so much better with bins than they do with a telescope.

 

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12 minutes ago, LukeSkywatcher said:

Is it?....

 

Yes it is. Since when did we start telling folks what questions they should ask on this forum :icon_scratch:

We always say that there is no such thing as a silly question and I think we should stick with that. The answers might not always be what the questioner expects but it's fine to ask the question to get a useful discussion started :smiley:

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8 minutes ago, John said:

Yes it is. Since when did we start telling folks what questions they should ask on this forum :icon_scratch:

We always say that there is no such thing as a silly question and I think we should stick with that. The answers might not always be what the questioner expects but it's fine to ask the question to get a useful discussion started :smiley:

exactly what was wrong with question I asked for their topic 

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There is nothing wrong with the original question. Just lots of ways to answer it. In the end each answer is a different perspective and, in this case, equally valid. 

Astronomical distances are vast. We all use different ways to make them understandable. Whether it's the time light has traveled, the vast energy of the light source or the physical distance, it all adds to the fascination. 

John

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53 minutes ago, John said:

Yes it is. Since when did we start telling folks what questions they should ask on this forum :icon_scratch:

We always say that there is no such thing as a silly question and I think we should stick with that. The answers might not always be what the questioner expects but it's fine to ask the question to get a useful discussion started :smiley:

NEVER. I obviously read your comment wrong.

There is NO such thing as a stupid question..............only the one you dont ask.

Apologies.

It was your emoticon of scratching your head which miss-lead me.

  On 10/13/2017 at 09:44, Ben the Ignorant said:

In stargazing the right question is not how far but how "How far" is a perfectly valid question to ask :icon_scratch:

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1 minute ago, LukeSkywatcher said:

NEVER. I obviously read your comment wrong.

There is NO such thing as a stupid question..............only the one you dont ask.

Apologies.

No problem Paul - I probably put the :icon_scratch: smiley in a place which confused the point that I was making :smiley:

The perils of e.communications ! :rolleyes2:

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I suppose a fainter object isn't necessarily further away any more than a brighter object is necessarily closer.  I guess object size comes into the thought pattern  too as well as what and how illuminated it is.  

However, I see nothing wrong with a What is the furthest object you can see and how far away is it type question.  There must be a valid answer and tbh I can't really see that it matters what units it is in.  As long as they are consistently comparable with a known norm and understood

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13 minutes ago, JOC said:

However, I see nothing wrong with a What is the furthest object you can see and how far away is it type question.  There must be a valid answer and tbh I can't really see that it matters what units it is in.  As long as they are consistently comparable with a known norm and understood

Exactly, whether it's km, miles, parsecs or light years, they are all valid measures of distance.

@alhiggs your question was, of course perfectly valid and not silly at all. John was not suggesting it was, he was merely trying to say that it's ok to ask any question you like on the forum (astro related of course!)

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My 1st view of the "Leo trio" galaxies was with my 20x90 bins. Still, faint smudges...............but visible.

Andromeda (the closest galaxy to us..........faint smudge).

Its all about magnification. 

I just LOVE using bins.............even a simple 10x50 pair. Its a different universe.

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Interesting question and thanks everyone for all the interesting replies :) 

In the the olden days of filmSLR I have often photographed @John's standard calibration distance as well :D

Ok, back to topic : I think I read that some Gamma-Ray Bursts can reach mag9 and they can be a really long way away

oh better still, a quick google before posting = mag5.8, no binocular needed, to see 1/2way across the universe !! at 7.5 billion light-years https://en.wikipedia.org/wiki/GRB_080319B

and https://www.nasa.gov/mission_pages/swift/bursts/brightest_grb.html

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