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

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

#131

Post by groby_b »

flukus wrote: post #118
groby_b wrote: post #108

Earlier quoted context omitted.

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.

Damn it. I only remembered "Andromeda", but you're right, that isn't where the story takes place. Same goes for "Sirens of Titan"

I guess I need to start re-reading :)

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

#132

Post by m463 »

Calamity wrote: post #116
ninkendo wrote: post #112

Earlier quoted context omitted.

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…

that's an interesting question.

If you traveled one light year at the speed of light, when you looked back you would see light from right after you left. But since you were traveling at the speed of light, your relativistic time for the journey would be zero.

So the light you observed would be proportional to your subjective time.

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

#133

Post by mod »

ekianjo wrote: post #100
divbzero wrote: post #80

Earlier quoted context omitted.

Then again, this photo mosaic spans just one arm of one galaxy in the visible universe.

We know that life only emerges in very specific conditions, that most planets do not have. We also know that even in very stable Earth, we have had billions and billions of species that developed and disappeared and we now only have a single specie with technological capabilities - and for a very short time at that, all things considered. If the universe is 'rich in life', most of it is probably micro-organisms that…

What are the chances that, from an outside perspective, that we are just one variety of life form on the planet?

Sure, they can make distinctions about which variety of us (e.g. humans, not dogs) have the most intelligence or something--but perhaps from an outside perspective, we all started from the same spontaneous event or whatever, and we're just many, many generations of that same lifeform.

In other words, maybe we're just being "racist," sort-of.

As an aside, is this a named theory or something? I'd like to read about it.

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

#134

Post by LilBytes »

jiggawatts wrote: post #120
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…

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!

Thanks for this! I will absolutely need to visit!

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

#135

Post by titzer »

LilBytes wrote: post #117
titzer wrote: post #111

Earlier quoted context omitted.

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).

I was in Canberra, which wasn't technically locked down for all that long, so I could probably have gone out more. It was generally very demotivating being there during the pandemic, so I mostly just farted around the lake on my bike. It's a big lake, though!

Cheers and happy trails. I'll return to Aus sometime!

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

#136

Post by efreak »

ekianjo wrote: post #100
divbzero wrote: post #80

Earlier quoted context omitted.

Then again, this photo mosaic spans just one arm of one galaxy in the visible universe.

We know that life only emerges in very specific conditions, that most planets do not have. We also know that even in very stable Earth, we have had billions and billions of species that developed and disappeared and we now only have a single specie with technological capabilities - and for a very short time at that, all things considered. If the universe is 'rich in life', most of it is probably micro-organisms that…

You might well be undercounting there, according to a 2016 study[0]:

> Earth could contain nearly 1 trillion species, with only one-thousandth of 1 percent now identified, according to a study from biologists. The estimate is based on the intersection of large datasets and universal scaling laws.

[0]: https://www.sciencedaily.com/releases/2016/05/160502161058.h...

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

#137

Post by efreak »

jonplackett wrote: post #127
groby_b wrote: post #108

Earlier quoted context omitted.

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.

Thanks I'll check these out! I guess I was thinking more about ones that have intergalactic travel. Do any of these actually have travel between galaxies or are they just set in an alt galaxy? Sorry, I din't really explain that thinking very clearly.

There's a few books here: https://www.reddit.com/r/scifi/comments/27i3y8/are_there_any...

Daily science fiction has a few very short stories, including this one: https://dailysciencefiction.com/science-fiction/science-fict...

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

#138

Post by spartanatreyu »

jonxa wrote: post #105
spartanatreyu wrote: post #99

Earlier quoted context omitted.

Unfortunately they don't seem to have a link to the final "full-res" image. I'd love to put that with my collection of other massive-res images. My screensaver pans between random spots on massive images in a folder.

Hey, would you share your library publicly or privately? I've been looking for something like this :) Also, check out dezoomify[0] [0] https://ophir.alwaysdata.net/dezoomify/dezoomify.html

Here's a link: https://1drv.ms/u/s!Ag4tKq5B7NFurglGuNpfDUKeHA7p?e=k9aejz

My libraries are always made of images I've found online. I've lost two libraries over time so I'm on my third one now.

I haven't added to my library in a while, but I might spend a few hours looking for some more images this weekend.

The current stats for my library:

At the moment it's 1.47gb for 75 images. I'm not sure where I have copied each image from, but I know some are either from ESO or NASA's image of the day, except that I find the original non-browser friendly images and download those. If I can get an image I like larger than my 5k screen, I'll add it to my library.

My average image size is 7156x5412.

My largest image is 324,000,000 pixels (18,000x18,000), pretty sure it's the Orion Nebula.

My smallest image is 2,958,400 pixels (so only 1720x1720), however any image that is surrounded by black (like a planet with no stars around may be cropped from time to time). Since my screensaver puts black around any images smaller than my 5k screen, it still works out. I'm pretty sure the smallest image is an image of Uranus from the Voyager that flew past it and I wanted to make sure I had an image of at least every planet in the Solar system and that was the best image of it I could find.

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

#139

Post by lensopra »

AnIdiotOnTheNet wrote: post #129
groby_b wrote: post #104

Earlier quoted context omitted.

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

I made no value judgement in my post.

"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?"

I wouldn't say it's exactly subtle to say "depends on what you mean by 'civilized'" and then immediately talk about the "trend away from reverence for gods". If you want to clarify, then clarify, but as it stands your comment is quite clear.

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

#140

Post by AnIdiotOnTheNet »

lensopra wrote: post #139
AnIdiotOnTheNet wrote: post #129

Earlier quoted context omitted.

I made no value judgement in my post.

"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?" I wouldn't say it's exactly subtle to say "depends on what you mean by 'civilized'" and the…

Oh, I see where you're coming from, but I was actually just being pedantic about what it means to be "civilized", since human civilization goes back thousands of years before electric light. "Civilized" in historical contexts means to be in an advanced stage of social and cultural development, that there is a lot of structure to people's lives, even if that structure employed violence in ways we find abhorrent.

The other meaning of "civilized", the one you seem to have intended, is more along the lines of being well-mannered and less violent, which is why I take your point.

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