Explanation: Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long. The emission nebula is found near the edge of an otherwise dark large molecular cloud in the southern constellation Ara, about 4,000 light-years away. Born in that region only a few million years ago, the massive young stars of the embedded Ara OB1 association sculpt the fantastic shapes and power the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that swept up and compressed the molecular gas. With image data from the Chilescope Observatory, a false-color Hubble palette was used to create this gorgeous wide-field image and shows emission from sulfur, hydrogen, and oxygen atoms in red, green, and blue hues. The field of view spans about four full Moons, corresponding to about 150 light years at the estimated distance of NGC 6188.
NGC 6188 (nebula) and NGC 6193 (cluster).
Source: Astro Drudis.com
Me being me, I am of course hugely interested in the stars that provide the ionization for these amazing nebulas.
Yesterday's APOD showed us that just one hot O-type star (Menkib) provides the ionization for the California Nebula. As for the Dragons of Ara, they are lit up by a small cluster of hot stars, NGC 6193. But there is chiefly one star that is responsible for doing the fantastic ionization: HD 150135.
All three (four, including HD 150135) of the brightest stars are massive luminous O class main sequence stars, 33-63 times as massive as the sun. They are around 10 times the size of the sun, but 6-8 times hotter and each is over 100,000 times as luminous. The primary star is the closest O3 star to Earth, 46,500 K,visually 18,000 times as bright as the sun, but because of its high temperature it is around three quarters of a million times more luminous including all wavelengths.
Ann
Re: APOD: NGC 6188: The Dragons of Ara (2018 Nov 07)
Posted: Wed Nov 07, 2018 11:57 am
by Indigo_Sunrise
*LIKE*
Re: APOD: NGC 6188: The Dragons of Ara (2018 Nov 07)
Posted: Wed Nov 07, 2018 2:55 pm
by Chris Peterson
Ann wrote: ↑Wed Nov 07, 2018 5:43 am
I was sort of hoping for an RGB image of this spectacular region, but that is rarely to be had nowadays... :wink:
Aside from the increased scientific value of narrowband images in many cases (which is why we see so many from professional observations), it is worth noting that they have a very practical value for amateur imagers: shooting through narrowband filters allows for quality data under light polluted skies. So observers who are not fortunate to have very dark skies can often do very good work without that posing a big problem (as it certainly does with ordinary color imaging through broadband filters). The shift towards narrowband amateur images may be partly aesthetic, it many be partly scientific, but it also has a strong practical aspect.
Re: APOD: NGC 6188: The Dragons of Ara (2018 Nov 07)
Posted: Wed Nov 07, 2018 10:12 pm
by Sa Ji Tario
The image of the day is a pareidolia of an image of the Sistine Chapel, the curved cloud on the left would be the arm of Adam and the one on the right the arm of the deity touching both index fingers
Re: APOD: NGC 6188: The Dragons of Ara (2018 Nov 07)
Posted: Wed Nov 07, 2018 10:28 pm
by neufer
Click to play embedded YouTube video.
Sa Ji Tario wrote: ↑Wed Nov 07, 2018 10:12 pm
The image of the day is a pareidolia of an image of the Sistine Chapel, the curved cloud on the left would be the arm of Adam and the one on the right the arm of the deity touching both index fingers
Maybe after a good manicure.
Re: APOD: NGC 6188: The Dragons of Ara (2018 Nov 07)
Posted: Wed Nov 07, 2018 11:41 pm
by Sa Ji Tario
Do not take this as a religious position but as an observation of the artistic without taking into account the mythical
Re: APOD: NGC 6188: The Dragons of Ara (2018 Nov 07)
Posted: Thu Nov 08, 2018 12:06 am
by Boomer12k
Really nice detail...many dragon shapes...
I have a Chinese, 5 toed, Imperial Dragon on the hood of my car... a 1972 Datsun 240Z.
So, I am into seeing "dragons"... if that is in the sky, so much the better...