APOD: The Great Carina Nebula (2018 Dec 27)

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APOD: The Great Carina Nebula (2018 Dec 27)

Post by APOD Robot » Thu Dec 27, 2018 5:07 am

Image The Great Carina Nebula

Explanation: A jewel of the southern sky, the Great Carina Nebula, also known as NGC 3372, spans over 300 light-years, one of our galaxy's largest star forming regions. Like the smaller, more northerly Great Orion Nebula, the Carina Nebula is easily visible to the unaided eye, though at a distance of 7,500 light-years it is some 5 times farther away. This gorgeous telescopic close-up reveals remarkable details of the region's central glowing filaments of interstellar gas and obscuring cosmic dust clouds. The field of view is over 50 light-years across. The Carina Nebula is home to young, extremely massive stars, including the stars of open cluster Trumpler 14 (above and left of center) and the still enigmatic variable Eta Carinae, a star with well over 100 times the mass of the Sun. Eta Carinae is the brightest star, centered here just below the dusty Keyhole Nebula (NGC 3324). While Eta Carinae itself maybe on the verge of a supernova explosion, X-ray images indicate that the Great Carina Nebula has been a veritable supernova factory.

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Ann
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Re: APOD: The Great Carina Nebula (2018 Dec 27)

Post by Ann » Thu Dec 27, 2018 10:24 am

That's a nice APOD that no one has commented on yet!

Today's APOD is an LRGB image, which I approve of. The colors seem "accurate", if saturated, to me.

It is interesting that the reddest part of the nebulosity is not close to the brightest, hottest stars. So maybe the faintly bluish nebulosity that seems to dominate where the hottest stars are located is due to blue starlight from the hot stars being mixed with red Hα emission, and maybe some green OIII and why not blue-green Hβ emission as well?

This APOD shows us what may be our galaxy's brightest star, Eta Carina, which looks yellowish in the APOD due to its being immersed in the Homunculus nebula. The blue light of Eta Carina itself is being strongly reddened by the Homunculus nebula. The Homunculus nebula itself is almost certainly a remnant of Eta Carina's violent outburst in 1837.

Today's APOD also shows us the open cluster Trumpler 14, which possibly contains our galaxy's hottest non-degenerate star, the O2-type supergiant HD 93129Aa.

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Re: APOD: The Great Carina Nebula (2018 Dec 27)

Post by NCTom » Thu Dec 27, 2018 1:09 pm

The energies involved in these star-forming regions are simply mind blowing! From a dusty nebula to a supernova in only a few tens of millions of years (or less)?

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Re: APOD: The Great Carina Nebula (2018 Dec 27)

Post by BDanielMayfield » Thu Dec 27, 2018 6:35 pm

NCTom wrote:
Thu Dec 27, 2018 1:09 pm
The energies involved in these star-forming regions are simply mind blowing! From a dusty nebula to a supernova in only a few tens of millions of years (or less)?
Indeed. The more massive a star is, the hotter and denser its core, and therefore the faster it will burn thru its fusible fuels. More mass equals a shorter supernova detonation fuse. KaBOOM!

But happily there's a natural means that cuts off the growth of stars so that very few ever get over 100 solar masses; stellar winds. The more massive the star, the greater its wind, so a point is reached where gas can no longer accrete into a newly forming protostar. If not for this the supernova rate would be much higher than it is.
"Happy are the peaceable ... "

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Re: APOD: The Great Carina Nebula (2018 Dec 27)

Post by Cousin Ricky » Fri Dec 28, 2018 3:22 am

Spot the Middle Finger Nebula in this photo!