APOD: Big Dipper Above and Below Chilean... (2017 May 09)

[APOD Robot]

Big Dipper Above and Below Chilean Volcanoes

Explanation: Do you see it? This common question frequently precedes the rediscovery of one of the most commonly recognized configurations of stars on the northern sky: the Big Dipper. This grouping of stars is one of the few things that has likely been seen, and will be seen, by every generation. The Big Dipper is not by itself a constellation. Although part of the constellation of the Great Bear (Ursa Major), the Big Dipper is an asterism that has been known by different names to different societies. Five of the Big Dipper stars are actually near each other in space and were likely formed at nearly the same time. Connecting two stars in the far part of the Big Dipper will lead one to Polaris, the North Star, which is part of the Little Dipper. Relative stellar motions will cause the Big Dipper to slowly change its configuration over the next 100,000 years. Pictured in late April, the Big Dipper was actually imaged twice -- above and below distant Chilean volcanoes, the later reflected from an unusually calm lagoon.

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[Ann]

Oh, that's a very nice Dipper! So beautiful!

This image underscores the fact that the Big Dipper can indeed look very big in the sky.

And it's a double Dipper too - there's another one in the water!

Nice!

Ann

[firstmagnitude]

Yes I can see star trails in the lagoon.

[RocketRon]

Connecting two stars in the far part of the Big Dipper will lead one to Polaris, the North Star,

Only if viewed in the Northern Hemisphere !!

Chile is rather in the Southern Hemisphere.

The Southern Cross and the 2 pointers give a general indication of the direction of south,
being that there is no similar 'pole star' in the southern sky.

[Boomer12k]

great shot.... would not want to be there when the volcanoes go off...

OK, I'll bite... why are there star trails in the lagoon, and not in the sky?
:---[===] *

[Nitpicker]

If there were star trails in the lagoon, they would be right-to-left. The lagoon was calm, but not perfectly calm.

Looks to be taken close to the Tropic of Capricorn, looking north. I can't see quite so much of the big dipper from my place. Polaris would be below the horizon (obviously) and below the bottom edge of the APOD.

[neufer]

OK, I'll bite... why are there star trails in the lagoon, and not in the sky?

If there were star trails in the lagoon, they would be right-to-left.
The lagoon was calm, but not perfectly calm.

• Which also explains why there are volcano trails in Chungará lake but not in the sky.

<<Chungará (hispanicized spelling of Aymara chunkara "pointed mountain") is a lake situated in the extreme north of Chile, in the Altiplano of Arica y Parinacota Region in the Lauca National Park. It is the 31st highest lake in the world (and the 12th highest in South America). It is near the volcanos Parinacota (6,348 m) and Pomerape (6,222 m). It was formed 8000 years ago, when a major collapse of the edifice of Parinacota produced an avalanche of 6 km³ of debris which blocked drainage pattern, thus creating the lake.>>

Looks to be taken close to the Tropic of Capricorn, looking north.

• Coordinates 18°S 69°W

[Nitpicker]

I must have misunderestimated (don't y'all miss Dubya) the position of the horizon. I figured the lagoon to be a bit further south than 18°.

[neufer]

I must have misunderestimated (don't y'all miss Dubya) the position of the horizon.

• Dubya the second-dimmest president of the United States...YES
  Dubhe the second-brightest star of Ursa Major (~ 5° above the horizon here)... no.

Note: Ursa Major is definitely too low on the horizon and the mirror image is too accurate (i.e., the mountains
should obscure more of the lower stars in the lake reflection) to wonder about some Photoshopping here.

I figured the lagoon to be a bit further south than 18°.

• World's highest lagoon

lagoon (n.) 1670s, lagune, earlier laguna (1610s), "area of marsh or shallow, brackish water beside a sea but separated from it by dunes," from French lagune or directly from Italian laguna "pond, lake," from Latin lacuna "pond, hole," from lacus "pond" (see lake (n.1)). Originally in reference to the region of Venice. The word was applied 1769 (by Capt. Cook) to the lake-like stretch of water enclosed in a South Seas atoll.

lake (n.1) "body of water surrounded by land and filling a depression or basin," early 12c., from Old French lack (12c., Modern French lac) and directly from Latin lacus "pond, pool, lake," also "basin, tank, reservoir" (related to lacuna "hole, pit"), from PIE *laku- "body of water, lake, sea" (source also of Greek lakkos "pit, tank, pond," Old Church Slavonic loky "pool, puddle, cistern," Old Irish loch "lake, pond"). The common notion is "basin."

[Case]

Connecting two stars in the far part of the Big Dipper will lead one to Polaris, the North Star,

Only if viewed in the Northern Hemisphere! Chile is rather in the Southern Hemisphere.

The two bright stars in the Big Dipper to use are Dubhe (α UMa, second brightest in UMa) and Merak (β UMa, fifth brightest), here on the left side of the ‘cup’. At 18.24° South, Polaris is 18.43° below the horizon, when the Big Dipper is up (showing that Polaris is a little off from the exact north celestial pole).
The distance ratio between these stars is 5.3:1 (28.7° to 5.4°), often cited as 5×, as that is enough precision to find Polaris in northern skies.

The brightness of Polaris is somewhere in between the brightness of Dubhe and Merak, but they’re all in the same ballpark (1.98 - 1.79 - 2.37).

Ursa Minor is of course home to some of the great galactic publishing and media corporations, such as Megadodo Publications.

[neufer]

Ursa Minor is of course home to some of the great galactic publishing and media corporations, such as Megadodo Publications.

• . https://www.themarysue.com/the-hitchhik ... alaxy-app/

<<Megadodo Publications are the original publishers of The Hitchhiker's Guide to the Galaxy. The company's headquarters were located on Ursa Minor Beta, in a pair of 30-story office buildings connected partway up their height by a walkway, so that the entire structure resembled a giant letter H. The relocation of the offices to a resort planet caused the company to lose much of its credibility among its customer base. One of the buildings was uprooted by a squadron of Frogstar fighters and brought to the Frogstar, in an attempt to capture and discipline rogue Galactic President Zaphod Beeblebrox. The Megadodo lobby is always filled with grubby-looking hitchhikers wanting to complain about the Guide's many inaccuracies. The president of Megadodo Publications is Zarniwoop, who is always too cool to see visitors. Megadodo was criticized by its customers for setting up an artificial universe in order to allow its editors and contributors to collect book information without leaving their offices. Notably secretive (or destructive) about their financial and historical records, the entire company was later (in the novel Mostly Harmless) bought out by Infinidim Enterprises, which stopped selling the Guide to hitchhikers entirely and eliminated all of what Megadodo had once stood for, much to the disapproval of employee Ford Prefect. The takeover was, in fact, part of a new plan by the Vogons to destroy Earth in all possible parallel dimensions – a plan that eventually succeeded.>>

[chuckster]

How far from our Sun would a spacecraft have to travel, before the constellations began to change ? What would be the first ones to distort ?

[Chris Peterson]

How far from our Sun would a spacecraft have to travel, before the constellations began to change ? What would be the first ones to distort ?

The stars are quite close, ranging from about 60-120 ly. So you'd only need to move a few light years before some distortion was quite apparent, and a few tens of light years for it to be so severe you wouldn't easily recognize the asterism anymore.

Google 3d big dipper and you'll get quite a few animations and images that show the stars of the Dipper from different angles.

[Nitpicker]

I think the volcanoes and lake have perhaps been misidentified. The author's Instagram page suggests the location to be San Pedro de Atacama, which is very close to the Tropic of Capricorn. I suspect this APOD looks northwards over Laguna Miscanti, but I haven't yet positively identified the location.

Edit Correction: Laguna Lejia: https://www.google.com.au/maps/place/Le ... 68!6m1!1e1

[Ann]

I think the volcanoes and lake have perhaps been misidentified. The author's Instagram page suggests the location to be San Pedro de Atacama, which is very close to the Tropic of Capricorn. I suspect this APOD looks northwards over Laguna Miscanti, but I haven't yet positively identified the location.

Edit Correction: Laguna Lejia: https://www.google.com.au/maps/place/Le ... 68!6m1!1e1

Tiny url?

TinyURL.com wrote:

The following URL:

https://www.google.com.au/maps/place/Le ... 68!6m1!1e1

has a length of 525 characters and resulted in the following TinyURL which has a length of 26 characters:

http://tinyurl.com/mlxwf4y

Ann

[Nitpicker]

Hi Ann,

So long as long URLs work, they don't bother me at all. I take it they bother you?

[neufer]

[b][color=#0000FF]Aguas Calientes Volcano on the right north of Laguna Lejía, Chile. To the left is the most active volcano of the region: Lascar, with constant releases of volcanic gas & eruptions going back to 1848.[/color][/b]

---

<<Aguas Calientes Volcano or Cerro Aguas Calientes, also called Simba, is a cone-shaped stratovolcano located 5 kilometres east of the Lascar volcano and 10 kilometres north of Laguna Lejía, Chile. One summit lava flow may be of Holocene age, but no evidence of historical activity is found. The volcano has a well formed summit crater. A small crater lake is found within the Aguas Calientes summit crater, making it one of the highest lakes in the world at an altitude of 5,870 metres. The lake has a surface area of 2,500 square metres and is tinged red from a population of microorganisms. The lake water is acidic and is frequently influenced by activity from Lascar, with winds carrying sulfuric acid and water vapour clouds to the crater lake. Precipitation was measured at 146 millimetres per year with most precipitation falling during the winter months, and strong UV irradiation. The lake has a bacterial ecosystem that is primarily reliant on photosynthesis but may also be influenced by hydrothermal activity from Aguas Calientes volcano. Research has found only limited numbers of bacterial taxa and a large number of DNA sequences that can't be identified as known phylogenetic groups. The lake has been studied as a possible terrestrial analogy to Mars.>>

---

High Lakes 2006 Scince Expedition.
CAPTAIN'S LOG #5: A Wonderful Nightmare...

<<Everybody is on the [Aguas Calientes Volcano] summit rim now, inside the crater. I cannot help it, I take a few steps forward. I want to see that lake. I hope it is worth all what we left on the slope. Worth? I am speechless. In front of my eyes, another crown jewel unravels, a magnificent ruby, a gem in the heart of an unlikely jewel box. What a beauty...The lake is so red that depending on the angles we look at it, it turns sometimes purple. It is now time to get into the crater and to the shores of this lake. Let's get acquainted. But before, I am taking a GPS measurement of the altitude. Including the lava cliff, Aguas Calientes towers at 5,930 m. The lake is at 5,870 m.

The red lake is about the size of that of Licancabur but rounder, almost looking like a red balloon. Its shores are circled by white deposits and the signs of a few ancient shorelines that are still marked on the ground. I take my poles and start walking around the lake, a first survey to see what is interesting and would be worth coming back to in a moment. Right away, some details are striking me: There is no life visible to the naked eye, conversely to Licancabur; There is no green algae, no algae at all for that matter. I continue. There is a small channel coming down from the rim. There is a little bit of ice still in it. I suppose that it is created seasonally by snow melt. That will be a place to come back to, especially the site where it connects with the lake.>>

[suicidejunkie]

Hi Ann,
So long as long URLs work, they don't bother me at all. I take it they bother you?

Personally, tiny urls bother me. What are they trying to hide and what spying is going on when all traffic bounces through tinyurl.com?

There's much better ways to do it (that we've always had available) anyways:
Tidy caption with honest, unhidden URL

[Ann]

Hi Ann,

So long as long URLs work, they don't bother me at all. I take it they bother you?

Well... yes, they turn me off a bit.

Also I don't trust them. Why are they so long? Do they contain anything, among their confusion of signs and letters, that may cause the link to break in the future?

As a Swede, I have to pay attention to the addresses of pictures I want to post. Any Swedish å, ä, and ö:s are no-nos is English-language addresses. And you can't even turn them into urls.

But I can see your point about tiny urls possibly hiding something, suicidejunkie... although I couldn't find your tidy, honest, unhidden url.

Ann

[neufer]

I think the volcanoes and lake have perhaps been misidentified. The author's Instagram page suggests the location to be San Pedro de Atacama, which is very close to the Tropic of Capricorn. I suspect this APOD looks northwards over Laguna Miscanti, but I haven't yet positively identified the location.

Edit Correction: Laguna Lejia: https://www.google.com.au/maps/place/Le ... 68!6m1!1e1

Tiny url?

The following URL: https://www.google.com.au/maps/place/Le ... 68!6m1!1e1
has a length of 525 characters and resulted in the following
TinyURL which has a length of 26 characters: http://tinyurl.com/mlxwf4y

Ann, who has criticized the URL, said she attempted to read the entire URL but failed to get through some of the details. "I wouldn't say -- yes," she told Nitpicker, "I turned through every page. As to whether or not I got through some of the details on some of the pages, no. But, yes, I attempted to read the entire URL."

Nitpicker admits he didn't read the full URL before posting it. Nitpicker said that since he was mostly concerned with edits to the URL, which didn't work the first time, so he paid the most attention to the edits needed to make it work. But he depended on his staff for most of the URL. "I read it as thoroughly as I could," he said. "You have an entire staff to really vet these things."

[Chris Peterson]

Hi Ann,
So long as long URLs work, they don't bother me at all. I take it they bother you?

Well... yes, they turn me off a bit.

Also I don't trust them. Why are they so long? Do they contain anything, among their confusion of signs and letters, that may cause the link to break in the future?

Any URL may break in the future. Long URLs are typically so because they contain a lot of data being passed to the page. But all you need to worry about is the stuff up to the end of the top level domain.

As a Swede, I have to pay attention to the addresses of pictures I want to post. Any Swedish å, ä, and ö:s are no-nos is English-language addresses. And you can't even turn them into urls.

Why not? All those characters are allowed in URLs, even in the domain name. If you can copy and paste it, anybody can click on it and get to the page. For example, http://www.clasohlson.com/se/Lödstation ... 40/40-9376

But I can see your point about tiny urls possibly hiding something, suicidejunkie... although I couldn't find your tidy, honest, unhidden url.

It's a valid concern. I'm cautious about clicking on any shortened URL.

[bystander]

Edit Correction: Laguna Lejia: https://www.google.com.au/maps/place/Le ... a,75y,90t/data=!3m8!1e2!3m6!1shttp:%2F%2Fwww.mountainphotography.com%2Fimages%2Fxl%2F20111015-Laguna-Lejia-Dawn.jpg!2e7!3e27!6s%2F%2Flh6.googleusercontent.com%2Fproxy%2Fk7uwE-rmd6dYjcE-JrJDK54ztf1WsgyLMYG4I3d_ALRajPLWtlY9XTPaPvLJJN4synjd_DzN6srAG7xY49T3w-mFYsEJJn0Hf_Nbu1N0mZGyDllHdU7fGP_XoUHinU2boBscwLHDPaZRn6y9BTQFtFoALEQVyZM%3Dw203-h135-k-no!7i1200!8i800!4m5!3m4!1s0x96a8393929418c3b:0x4dd31bbfdeeb088c!8m2!3d-23.4956101!4d-67.6930468!6m1!1e1

If you just wanted the image, you could extract that from the google garbage
http://www.mountainphotography.com/imag ... a-Dawn.jpg

If you wanted the map, too, you could add the simplified map url. (You'll probably have to hit refresh)
https://www.google.com.au/maps/place/Le ... a,75y,90t/

[Nitpicker]

Thanks, but I specifically wanted the link to open up the image in Google Maps (which is the tool I spent too much time finding it with -- there are a lot of lakes and volcanoes in northern Chile), as I wanted to show it all in one fell swoop.

And in this context, I tend to prefer direct links, in all their ugly glory, rather than tiny or tidy links, and not just because they are quicker to add (I did test it, too). Maybe I'm weird? Apologies to those I've bothered.

I was also rushing a bit, as I was in the process of correcting myself before anyone else. I also felt another sense or urgency, as a more experienced passenger on The Starship, was starting to makes waves about potential fakery in this APOD. I remain your obedient (and hopefully useful) passenger.

Love,
Nitpicker.

[Nitpicker]

Ann, who has criticized the URL, said she attempted to read the entire URL but failed to get through some of the details. "I wouldn't say -- yes," she told Nitpicker, "I turned through every page. As to whether or not I got through some of the details on some of the pages, no. But, yes, I attempted to read the entire URL."

Nitpicker admits he didn't read the full URL before posting it. Nitpicker said that since he was mostly concerned with edits to the URL, which didn't work the first time, so he paid the most attention to the edits needed to make it work. But he depended on his staff for most of the URL. "I read it as thoroughly as I could," he said. "You have an entire staff to really vet these things."

My mistake. I didn't think it necessary to admit that I didn't read any of the legislation in the recent Republican health care bill in your fair union. God Save the Queen.

Trigger Warning! The following link may contain enough characters to be considered bothersome:
http://edition.cnn.com/2017/05/05/polit ... alth-care/

[neufer]

My mistake. I didn't think it necessary to admit that I didn't read any of the legislation in the recent Republican health care bill in your fair union. God Save the Queen.

You are weird! (I really expected this one to go over the heads of you & Ann.)