APOD: Pan-STARRS Across the Lagoon (2019 Apr 25)

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APOD: Pan-STARRS Across the Lagoon (2019 Apr 25)

Post by APOD Robot » Thu Apr 25, 2019 4:09 am

Image Pan-STARRS Across the Lagoon

Explanation: Ridges of glowing interstellar gas and dark dust clouds inhabit the turbulent, cosmic depths of the Lagoon Nebula. Also known as M8, the bright star forming region is about 5,000 light-years distant. But it still makes for a popular stop on telescopic tours of the constellation Sagittarius, toward the center of our Milky Way Galaxy. Dominated by the telltale red emission of ionized hydrogen atoms recombining with stripped electrons, this stunning view of the Lagoon is over 100 light-years across. At its center, the bright, compact, hourglass shape is gas ionized and sculpted by energetic radiation and extreme stellar winds from a massive young star. In fact, the many bright stars of open cluster NGC 6530 drift within the nebula, just formed in the Lagoon several million years ago. Broadband image data from Pan-STARRS (Panoramic Survey Telescope & Rapid Response System) was combined with narrowband data from amateur telescopes to create this wide and deep portrait of the Lagoon Nebula.

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orin stepanek
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Re: APOD: Pan-STARRS Across the Lagoon (2019 Apr 25)

Post by orin stepanek » Thu Apr 25, 2019 12:09 pm

Wow! Nice; reminds me of a flower; a Rose in fact! Very pretty, the Lagoon Nebula in Red is! :clap: :thumb_up: :yes:
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Too soon?

Post by neufer » Thu Apr 25, 2019 2:28 pm

Baboon, balloon, bassoon, buffoon, cartoon, cocoon, doubloon, dragoon, festoon, harpoon, high noon, immune, impune, lampoon, maroon, monsoon, platoon, pontoon, raccoon, saloon, spitoon, tycoon, typhoon.
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Re: APOD: Pan-STARRS Across the Lagoon (2019 Apr 25)

Post by Ann » Thu Apr 25, 2019 5:38 pm

The Lagoon Nebula. László Francsics / Royal Museums Greenwich.
Source: https://astronomynow.com/2015/08/06/her ... francsics/
Like most Lagoons, the Lagoon Nebula is definitely deepest in the middle!

The superb picture at right really hints at what I think is the true structure of the Lagoon. Note at lower left a billowing red ridge (with a dark dust "man" standing near the lower left corner, staring to the upper left with his one misplaced eye). Above the red ridge is cluster NGC 6530, and the hot stars of NGC 6530 are undoubtedly responsible for carving out this red ridge and clearing a cavity behind it. A long dark "waterfall" (or "dust flow"?) separates most of the members NGC 6530 from bright blue star 9 Sagittarius and slightly less bright blue star HD 164816.

Note the blue light surrounding 9 Sagittarius. I interpret this as a faint reflection nebula, which in turn means (or so I think) that 9 Sagittarius is so young that it hasn't had time to blow away all the dust in its vicinity, and the ambient dust reflects blue light from this blisteringly hot O4V star.

By contrast, the stars on the left side of the long dark dust flow don't show obvious signs of being surrounded by reflection nebulas, even thought the lit-up dust wall behind it displays a purplish hue. These stars have had time to (mostly) clear away the gas and dust that they were born out of from their immediate vicinity, but the red ridge in front of them and the purplish wall behind them shows where gas and dust has piled up.

According to this paper, NGC 6530 is only about 2.3 million years old. The paper also made the assumption that 9 Sgr is part of NGC 6530. My amateur opinon is that 9 Sgr appears younger than the stars on the other side of the dark dust flow.

Can you see the bottom of it?
Flickr/Otavio Nogueira
Now take a look at the bright center of the Lagoon Nebula, where the hot massive star Herschel 36 has just been born, and its tattered birth nebula, known as the Hourglass Nebula, is brilliantly lit up. There can be no doubt that Herschel 36 and the Hourglass Nebula are situated in the (currently) deepest past of the Lagoon Nebula. In the heart of Sagittarius, star formation progresses farther and farther away from us, deeper and deeper into the hidden depths of this deep cosmic Lagoon.

Star formation in Corona Australis. Photo: Marco Lorenzi.








Star formation typically takes place at one end of elongated dust structures, like the one you can see in the picture at right of a region in Corona Australis. Stars are being born at one end of a long "tube" of gas and dust, and the dusty filament of star forming material goes on for light years behind the actual birth site of the stars. In some cases, star formation "eats" its way deeper and deeper into the cosmic river of yummy molecules, and the "river" gets "pregnant" again and again with more and more stars. The dust lanes, however, wither away as more and more of their atoms and molecules get locked up inside stars.

Ann
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orin stepanek
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Re: Too soon?

Post by orin stepanek » Thu Apr 25, 2019 11:12 pm

neufer wrote:
Thu Apr 25, 2019 2:28 pm
Baboon, balloon, bassoon, buffoon, cartoon, cocoon, doubloon, dragoon, festoon, harpoon, high noon, immune, impune, lampoon, maroon, monsoon, platoon, pontoon, raccoon, saloon, spitoon, tycoon, typhoon.

Ya forgot hit tune; sand dune; harvest moon; coming soon; & probably a few more. :wink:
Orin

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Re: Too soon?

Post by neufer » Fri Apr 26, 2019 3:46 am

orin stepanek wrote:
Thu Apr 25, 2019 11:12 pm
neufer wrote:
Thu Apr 25, 2019 2:28 pm

Baboon, balloon, bassoon, buffoon, cartoon, cocoon, doubloon, dragoon, festoon, harpoon, high noon, immune, impune, lampoon, maroon, monsoon, platoon, pontoon, raccoon, saloon, spitoon, tycoon, typhoon.
Ya forgot hit tune; sand dune; harvest moon; coming soon; & probably a few more. :wink:
https://www.etymonline.com/search?q=lagoon wrote:
<<lagoon (n.) 1670s, lagune, earlier laguna (1610s), "area of marsh or shallow, brackish water beside a sea but separated from it by sand dunes," from French lagune or directly from Italian laguna "pond, lake," from Latin lacuna "pond, hole," from lacus "pond." 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.>>
.....................................................................................
<<lampoon (n.) "A personal satire; abuse; censure written not to reform but to vex" [Johnson], 1640s, from French lampon (17c.), a word of unknown origin, said by French etymologists to be from lampons "let us drink," which is said to have been a popular refrain for scurrilous songs, in which case it would be originally a drinking song.>>
Art Neuendorffer

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orin stepanek
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Re: APOD: Pan-STARRS Across the Lagoon (2019 Apr 25)

Post by orin stepanek » Fri Apr 26, 2019 11:37 am

I give you two :thumb_up: Art
Orin

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Re: APOD: Pan-STARRS Across the Lagoon (2019 Apr 25)

Post by neufer » Sat Apr 27, 2019 2:36 am

https://en.wikipedia.org/wiki/SPECULOOS wrote:
<<SPECULOOS (Search for habitable Planets EClipsing ULtra-cOOl Stars) is a project in development that consists of four Ritchey–Chrétien telescopes of 1-metre primary aperture, made by ASTELCO. Each telescope will be equipped with a NTM-1000 robotic mount, that will be installed at the Paranal Observatory in Chile to search for Earth-sized exoplanets around 1000 ultra-cool stars and brown dwarfs.

The system comprises four telescopes called Europa, Io, Callisto, and Ganymede equipped with cameras sensitive in the near-infrared, the wavelength range in which ultra-cool stars and brown dwarfs emit most of their light.>>
Art Neuendorffer