alhiggs Posted October 13, 2017 Share Posted October 13, 2017 with a pair of 20x80 bbinoculars how many miles into space can you see Link to comment Share on other sites More sharing options...
John Posted October 13, 2017 Share Posted October 13, 2017 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 ! Link to comment Share on other sites More sharing options...
Ben the Ignorant Posted October 13, 2017 Share Posted October 13, 2017 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. Link to comment Share on other sites More sharing options...
John Posted October 13, 2017 Share Posted October 13, 2017 7 minutes ago, Ben the Ignorant said: In stargazing the right question is not how far but how faint you can see.... "How far" is a perfectly valid question to ask Link to comment Share on other sites More sharing options...
MarsG76 Posted October 13, 2017 Share Posted October 13, 2017 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. Link to comment Share on other sites More sharing options...
alhiggs Posted October 13, 2017 Author Share Posted October 13, 2017 that's along way thank you.guys for your help Link to comment Share on other sites More sharing options...
oobydooby Posted October 13, 2017 Share Posted October 13, 2017 1 hour ago, alhiggs said: that's along way thank you. That's a bit of an understatement! Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted October 17, 2017 Share Posted October 17, 2017 On 10/13/2017 at 09:54, John said: "How far" is a perfectly valid question to ask 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. Link to comment Share on other sites More sharing options...
John Posted October 17, 2017 Share Posted October 17, 2017 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 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 Link to comment Share on other sites More sharing options...
alhiggs Posted October 17, 2017 Author Share Posted October 17, 2017 8 minutes ago, John said: Yes it is. Since when did we start telling folks what questions they should ask on this forum 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 exactly what was wrong with question I asked for their topic Link to comment Share on other sites More sharing options...
westmarch Posted October 17, 2017 Share Posted October 17, 2017 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 Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted October 17, 2017 Share Posted October 17, 2017 53 minutes ago, John said: Yes it is. Since when did we start telling folks what questions they should ask on this forum 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 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 Link to comment Share on other sites More sharing options...
John Posted October 17, 2017 Share Posted October 17, 2017 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 smiley in a place which confused the point that I was making The perils of e.communications ! Link to comment Share on other sites More sharing options...
JOC Posted October 17, 2017 Share Posted October 17, 2017 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 Link to comment Share on other sites More sharing options...
Stu Posted October 17, 2017 Share Posted October 17, 2017 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!) Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted October 17, 2017 Share Posted October 17, 2017 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. Link to comment Share on other sites More sharing options...
John Posted October 17, 2017 Share Posted October 17, 2017 On 13/10/2017 at 09:31, alhiggs said: with a pair of 20x80 bbinoculars how many miles into space can you see If you leave the objective lens caps on, you can see about 15mm Link to comment Share on other sites More sharing options...
SilverAstro Posted October 18, 2017 Share Posted October 18, 2017 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 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 Link to comment Share on other sites More sharing options...
Dave In Vermont Posted October 18, 2017 Share Posted October 18, 2017 To us here on this third rock from the star, the speed-of-light seems mighty fast indeed. But from the perspective of a photon of light? You decide: Have a Nice Trip! Dave Link to comment Share on other sites More sharing options...
Wobbly Bob Posted October 18, 2017 Share Posted October 18, 2017 Not how many miles but how many photons, we astronomers are light gatherers. Link to comment Share on other sites More sharing options...
Dave In Vermont Posted October 18, 2017 Share Posted October 18, 2017 And our telescopes are Time-Machines. Put that in your H.G. Wells and smoke it! Starry Skies - Dave Link to comment Share on other sites More sharing options...
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