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I've travelled to farms at night, and away from civilation. I don't really know alot about astronomy, but my goal is to see something like this: enter image description here

Stars, lots of them, but that "thick purple cluster of gas right in the center". I want to see that.

I assume that on a very very dark day, we would be able to see this, but sometimes I only see stars, just lots and lots of stars, something like this:

enter image description here I want to see this "thick cloud cluster, which I assume is the milky way". How do I see this? How on some days do I only see just stars and stars, when I really want to see this main beauty?

K Split X
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    Your second photo is a reasonable recreation of what one might expect to see with the naked eye. The first photo has likely been taken with an exposure time of at least 30 seconds at ISO 1600 and is a good example of how one can see much more in an astrophotograph than with the naked eye. If you can, repeat the trip and take a DSLR and tripod and have a go! – MartinV Aug 09 '17 at 08:02
  • @MartinV, actually the first image you can actually see with the naked eye. If you recall the los angeles blackout in the 90's, they say this, with their eye only. https://s-media-cache-ak0.pinimg.com/originals/9c/8d/6b/9c8d6b87da4801ff77d5d4da4dbd49fa.jpg – K Split X Aug 09 '17 at 10:54
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    @MartinV is correct. Unless you want to believe everything you read on the internet! – adrianmcmenamin Aug 09 '17 at 11:23
  • @KSplitX But there again that photo was taken with a camera that can capture things the eye can't. I would be highly skeptical if that image was really what the human eye could see. – zephyr Aug 10 '17 at 18:49
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    @KSplitX That "photo" is not real - the top showing the Milky Way and the bottom showing LA are from 2 separate photographs: https://hoaxeye.com/2017/05/28/photo-of-la-blackout-in-1994/ – pacoverflow Apr 11 '18 at 06:12

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"thick purple cluster of gas right in the center". I want to see that.

First off, the human eye is a wonderful device, but it's no match for modern cameras. We can't see colors at such low levels of light. We're all colorblind in those conditions. Only cameras continue to see color when illumination is low.

As a result, when looking at objects such as nebulae or galaxies, including our own, all you see is a black-and-white image. Even with telescopes, the human eye still doesn't see colors in these objects.

There is exactly one single exception - the Orion nebula, which is by far the brightest of all. Some observers, after a bit of practice, can begin to distinguish a few shades of color there.

Planets, and some stars, are different. These objects are much more bright. The human eye has no trouble seeing color where color exists here. E.g. Jupiter is a slight shade of yellow, Betelgeuse is quite clearly red, etc.

purple

I'm pretty sure the Milky Way is not purple. That's probably just a processing artifact. Go on Astrobin and search for "milky way" for a lot more examples - they tend to not look very purple usually.

https://www.astrobin.com/

I want to see this "thick cloud cluster, which I assume is the milky way". How do I see this? How on some days do I only see just stars and stars, when I really want to see this main beauty?

There are two main obstacles to doing astronomy at the bottom of an ocean of air: atmospheric turbulence (a.k.a. "seeing") and light pollution.

Seeing affects observing high resolution objects such as planets and double stars when seen in telescopes. It's caused by air eddies and vortices that muddy the image. It's of no interest here so we can ignore it for this discussion.

Light pollution affects observing faint objects such as galaxies (including our own), nebulae, and star clusters. It's caused by light from artificial sources (city lights, industrial lights, cars, etc) going up, being reflected on particles in the air, then going back down. It makes the sky seem to "glow". It drowns out those objects which are not very bright - and galaxies tend to not be bright.

There's only one way to avoid light pollution: go far away from human settlements and facilities. The desert and the open sea are not light polluted.

Google "light pollution map" for some websites that will help you choose a dark site. Here's one example out of many:

http://www.jshine.net/astronomy/dark_sky/

Recently I've visited Death Valley. The surrounding area has essentially zero light pollution. Even driving 30 minutes out of Ridgecrest you're already under a very dark sky. I took the opportunity to show my kids how a dark sky really looks like.

The Milky Way is very clearly visible. Wherever you look, there are stars upon stars. Take a pair of binoculars, point them at random places in the sky, and even more stars are visible. There are star clusters that you could chance upon just by sweeping the sky with the binoculars, and they look like someone threw a handful of diamonds on black velvet. Little shooting stars are visible often. It's extraordinary.

It should be noted that the Milky Way is not visible during the winter months (December – February). It's best to try to watch it in June – August. Even later in the year (September – November) it's still visible in the West, just before it sets, a short time after nightfall. If you're an early riser, you can see it before daybreak in the spring (March – May).

You need to wait until the sky goes completely dark after sunset. That means 1.5 hours after sunset, or more. To determine the precise moment of sunset, go on Google or Wolfram Alpha and search for "sunset today". Then add 90 minutes to the result.

You will also need to time your visit to a night when the Moon is not visible. The Moon must be below horizon, otherwise it would cause some "light pollution" of its own. A few days before and after the new moon are the best time for this.

You could go on Wolfram Alpha and search for "next new moon" or even "new moon in september" and it will give you the date. Several days plus or minus that date should be fine.

http://www.wolframalpha.com/

TLDR: A moonless night in the summer, in a desert or some other unpopulated area, 1.5 hours after sunset or later.

Florin Andrei
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    Thank you very much for the information. I enjoyed the entire read. I have a question though. "It should be noted that the Milky Way is not visible during the winter months". Why not? I'm currently in North America, does this effect anything? – K Split X Aug 10 '17 at 01:03
  • @KSplitX The Sun appears to move slowly in relation to the fixed stars. In one year it makes a full circle, going back to where it started. During the winter months, the Sun appears to be close to the portion of the sky where the Milky Way is seen. That means the Milky Way would rise and set with the Sun - it's high in the sky during the day, when you cannot see it. During summer, the Sun is pretty much opposite to the Milky Way in the sky. That means the Milky Way rises at night, when you can see it. It does not matter where you're located, we all see the position of the Sun the same way. – Florin Andrei Aug 10 '17 at 18:05
  • The Milky Way (MW) passes through Perseus, Gemini, Monoceros, Puppis, -- constellations visible in the northern hemisphere winter. So the MW is definitely "up" and not blocked by the Sun. However, the winter MW is not as brilliant as the summer MW (Aquila, Sagittarius, Scorpius), so you need to very dark sky to see the glow of the winter Milky Way. – JohnHoltz Aug 11 '17 at 17:48
  • @FlorinAndrei How did the Milky Way appear to your naked eye from Death Valley? Was it any better than OP's second photo? – pacoverflow Apr 11 '18 at 06:19
  • @pacoverflow There's no real way to compare a photo with what the eye actually sees; a photo is dead, it's nothing like the actual living image. All I can say is - if you've only seen the sky from urban areas, in a dark sky region it's mind boggling. It's like a river of stars. Stars like dust, everywhere you look. With binoculars it gets even better. Totally worth it. Plan your trip well ahead of time, and do it. – Florin Andrei Apr 12 '18 at 00:00
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You might want to try a very dark night instead of a "dark day". :-)

The "cluster of gas" that you mention is from countless stars. From a dark site, it looks like clouds, but you soon realize that they are not moving. It is not as well defined as in the photo, but it is impressive.

In addition to needing a dark site far from lights, you need to look at the correct time of day and night. You want to look when the constellation of Sagittarius is at its highest.

JohnHoltz
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  • Do you know how I can find that out? – K Split X Aug 09 '17 at 14:30
  • The "cluster of gas" is from gas, not countless stars (not to mention the fact that astronomers have counted the stars and wind up with 100-400 billion stars in our Milky Way and ~5000 visible by the naked eye from Earth). Most of that gas is obscuring dust from the interstellar medium. – zephyr Aug 10 '17 at 18:52
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Darkest skies I've seen were in the outback of Australia, perhaps 20km from the nearest (small) town. Still couldn't see purple clouds though. The naked eye view was more like your 2nd image.

Nick
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