Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

astroanarchy.blogspot.com

Post reply on HN
Print view View original

111–120 of 141 posts

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#111

Post by titzer »

LilBytes wrote: post #109
titzer wrote: post #55

Earlier quoted context omitted.

And in the modern world, we are blind to it because of light pollution. It's sad. One of the most amazing experiences ever, a truly dark, clear sky at night, is only accessible if you travel off-continent.

You better believe it. I couldn't believe what the sky looked like at night when I moved to Australia from the UK. And I was in a relatively suburban setting then. I regularly go camping now maybe every 1-2 months out into the outback. And the night sky, without exaggeration and using the words here sensibly, literally, never, gets old. In my 19 years in the UK I never saw anything like it. Edit: Admittedly I think t…

Ah man, damn it! I spent 10 months in Australia, but most of it was during lockdown, and I didn't have a car. I only got 1 week of travel and didn't see much of the stars.

My best experience was in Fiji and New Zealand, but I imagine that the outback could be even better.

I've gone out to Mojave on super clear nights. Vegas is easily visible, almost like a sunrise. The Great Smoky Mountains look good on paper (light pollution map), but in practice they are quite clowdy / hazy, so viewing isn't good. I imagine northern Canada could also be quite good.

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#112

Post by ninkendo »

jonplackett wrote: post #101
m463 wrote: post #89

Earlier quoted context omitted.

Too bad it's so far away. There's that saying... too young to explore the world, too old to explore the universe. When our children's children learn to extend their life, or figure out some sort of suspended animation, or pload their brain... what wonders they will see.

Even with extended life span ain't nobody ever going to another galaxy. Even if we could travel at the speed of light, it would take 2.5 million years just to get to the nearest galaxy.

If we could travel appreciably close to the speed of light, the journey could be close to instantaneous for the traveler. (Depending obviously on how close to light speed we’re talking about.)

Time dilation is a nice property.

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#113

Post by spindle »

krick wrote: post #110

Do I understand correctly, that all colours on these pictures always are purely artificial? That is, all visible light we can see through any telescope is always white, and only some minor differences in the spectrum, invisible to us, are used to detect what elements there are, and then semi-artistically colorize the picture based on that data?

Many objects in the sky are brightly coloured.

Astrophotograpers often add artificial colours on top of (or instead of) the actual colours.

Plus, much of what you see from astronomers (although not from this case) is taken in non-optical parts of the electromagnetic spectrum (e.g. radio waves or x-rays), so those pictures are necessarily artificially coloured.

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#114

Post by mkoubaa »

groby_b wrote: post #104
AnIdiotOnTheNet wrote: post #48

Earlier quoted context omitted.

Depends on what you mean by "civilized", but I take your point. I do wonder, however, if there isn't a correlation between the increase of light pollution and the trend away from reverence for gods. In other words, does the ability to see the grandeur of the heavens on a daily basis influence us to believe in greater beings?

Why is a belief in "greater beings" good or helpful?

Humility

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#115

Post by davchana »

wahern wrote: post #74
uhtred wrote: post #70

Earlier quoted context omitted.

Agreed. I very recently was thinking about how humans up to a few hundred years ago must have seen the most breath taking night skies. Imagine a native American standing in a clearing at night 2000 years ago, with zero light pollution, looking at the night sky and just wondering what it is all about.

Even w/ a clear desert sky hundreds of miles from the nearest city (e.g. middle of Nevada), the sky looks nothing like these pictures. Astrophotography uses exposure times many multiples--and usually several orders of magnitude--longer than the human eye. Can you see the Milkyway? No, not really; not without prompting. If you have no idea what to look for, the disc is just a barely imperceptible, slight increase in o…

Maybe its clouds, or air quality, or general deteriorating climate, about 30 years ago, my village in plains of Punjab, we used to see lots of stars, constellations, & planets along with satellites at night time. Maybe absence of tv, mobile, culture of sleeping on roof in summers, made us more aware of stars. Full moon nights were like brightly lit. No moon nights were amazingly dark. We could see shadows in moon light. Things were just like day, but in dark blue grey color. We always saw the north pole star, few other groups, & watched milky way moving from side to side in night. Did not know its name, we call it SkyRiver in our language (Galaxy). For reference, now I am in northern california small town.

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#116

Post by Calamity »

ninkendo wrote: post #112
jonplackett wrote: post #101

Earlier quoted context omitted.

Even with extended life span ain't nobody ever going to another galaxy. Even if we could travel at the speed of light, it would take 2.5 million years just to get to the nearest galaxy.

If we could travel appreciably close to the speed of light, the journey could be close to instantaneous for the traveler. (Depending obviously on how close to light speed we’re talking about.) Time dilation is a nice property.

Indeed - something often misunderstood as always recorded from the perspective of a third party observer.

Quick follow up question. If you did depart and travelled at near-ligth speed to another galaxy, arrived there in a few seconds and then looked back at the earth - would it appear as only a few seconds have passed for the earthlings back home as well?

By the same token, if you are actively watching another galaxy as you travel at near-light speed towards it - will you be watching that galaxy "age" at an extremely fast pace throughout the journey?

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#117

Post by LilBytes »

titzer wrote: post #111
LilBytes wrote: post #109

Earlier quoted context omitted.

You better believe it. I couldn't believe what the sky looked like at night when I moved to Australia from the UK. And I was in a relatively suburban setting then. I regularly go camping now maybe every 1-2 months out into the outback. And the night sky, without exaggeration and using the words here sensibly, literally, never, gets old. In my 19 years in the UK I never saw anything like it. Edit: Admittedly I think t…

Ah man, damn it! I spent 10 months in Australia, but most of it was during lockdown, and I didn't have a car. I only got 1 week of travel and didn't see much of the stars. My best experience was in Fiji and New Zealand, but I imagine that the outback could be even better. I've gone out to Mojave on super clear nights. Vegas is easily visible, almost like a sunrise. The Great Smoky Mountains look good on paper (light…

Man that sucks! Were you mostly in Melbourne during this time? They were in lock down for a long time but most of the rest of the country was only 1-2 months of severe lock down (hard limits on leaving the suburb and then later, a hard 50KM limit from your place of residence).

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#118

Post by flukus »

groby_b wrote: post #108
jonplackett wrote: post #86

Holy crap the universe is massive. It occurred to me the other day that there's barely any science fiction that even occurs outside our own galaxy (Star Wars being the exception that proves the rule). And if it does it's usually something from Andromeda right 'next door'. Even Star Trek only leaves the galaxy maybe one time, and that requires the help of Q.

Wait, what? In what universe is there "barely any science fiction" outside our galaxy? Lensman. The entire Revelation Space series. Beyond the Aquila Rift. Player of Games. Algebraist. Sirens of Titan. Perry Rhodan. And that's off the top of my head. There's quite a bit of SF (both good and trash, and I think the above list has both :) happening outside our galaxy.

> The entire Revelation Space series

Fantastic series and probably my favorite writer, but because it mostly sticks within known physics nearly all of it takes palce within about 20 light years of earth with the exception of Galactic North and maybe a few other side stories. Earth doesn't get much of a mention, but the main character is from Mars.

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#119

Post by no-s »

quesera wrote: post #82
wahern wrote: post #74

Earlier quoted context omitted.

Even w/ a clear desert sky hundreds of miles from the nearest city (e.g. middle of Nevada), the sky looks nothing like these pictures. Astrophotography uses exposure times many multiples--and usually several orders of magnitude--longer than the human eye. Can you see the Milkyway? No, not really; not without prompting. If you have no idea what to look for, the disc is just a barely imperceptible, slight increase in o…

I agree with your larger premise, but: > Can you see the Milkyway? No, not really This is not my experience. I have seen the Milky Way very clearly from a few locations in the US. None are particularly remote -- all are just a few hours drive from the large cities I've lived in. Winter months are clearer than summer.

> I have seen the Milky Way very clearly from a few locations in the US.

I agree. heck, I remember stargazing in rural New Mexico in the 70's, the moonless night sky was luminous to the dark-adapted eye. The Milky Way was a river of stars, bright enough to read by (well, distinguish the words on the page, I don't remember spending much time reading...)

Re: Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky

#120

Post by jiggawatts »

LilBytes wrote: post #109
titzer wrote: post #55

Earlier quoted context omitted.

And in the modern world, we are blind to it because of light pollution. It's sad. One of the most amazing experiences ever, a truly dark, clear sky at night, is only accessible if you travel off-continent.

You better believe it. I couldn't believe what the sky looked like at night when I moved to Australia from the UK. And I was in a relatively suburban setting then. I regularly go camping now maybe every 1-2 months out into the outback. And the night sky, without exaggeration and using the words here sensibly, literally, never, gets old. In my 19 years in the UK I never saw anything like it. Edit: Admittedly I think t…

For me the real shock was Lord Howe Island, which is 600km from the mainland and surrounded by nothing but open ocean. At night, the entire island has only a few dozens lights on for marine safety, powered by a diesel generator.

On a clear, moonless night the sky is just unbelievable. You can see several galaxies with the naked eye, which is not something I had experienced before!

Post reply on HN