APOD: Stardust and Starlight in M78 (2019 Mar 08)

[APOD Robot]

Stardust and Starlight in M78

Explanation: Interstellar dust clouds and bright nebulae abound in the fertile constellation of Orion. One of the brightest, M78, is near the center in this colorful telescopic view, covering an area north of Orion's belt. At a distance of about 1,500 light-years, the bluish nebula itself is about 5 light-years across. Its blue tint is due to dust preferentially reflecting the blue light of hot, young stars in the region. Dark dust lanes and other nebulae can easily be traced through the gorgeous skyscape that includes many Herbig- Haro objects, energetic jets from stars in the process of formation. But missing from this image is McNeil's nebula. A major discovery only recognized in 2004, the enigmatic, variable nebula was found along the dark lane of dust above and right of larger M78. McNeil's nebula is associated with a protostar and seen to be sometimes present and sometimes absent in photos of the well-imaged region. McNeil's nebula faded from view late last year and is still absent in this deep image recorded in February 2019.

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[intipunku]

is that God looking through the blue gas?

[orin stepanek]

M78 is very beautiful; like fine art!

[neufer]

In these images we compare a colour picture of the Messier 78 region taken in 2006 with the 4-metre Mayall telescope at Kitt Peak, Arizona (below) with a new image that was captured using the Wide Field Imager camera on the MPG/ESO 2.2-metre telescope at the La Silla Observatory, Chile (above). McNeil's Nebula is almost completely invisible in the older image but very prominent in the new picture.

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<<McNeil's Nebula is a variable nebula discovered January 23, 2004 by Jay McNeil of Paducah, Kentucky. "Only recently discovered by amateur astronomer Julian W. McNeil II [Jay McNeil], this peculiar looking object is currently classified as a cometary-type reflection nebula. The newborn nebula was found while processing a wide field image of Orion's Messier 78 nebular region which was taken from McNeil's suburban backyard using a 3-inch refractor. Images taken of the area before September 2003 show absolutely no signs of the nebula nor its ruddy illuminating star, which can be seen near the object's southern apex. Preliminary research by Bo Reipurth (Univ. of Hawaii) reveals that the nebula was created when the deeply imbedded fetal star previously catalogued as IRAS 05436-0007 somehow erupted and went into outburst. The young star's sudden increase in brightness consequently resulted in the surrounding cocoon of gas and dust becoming illuminated much like a lighthouse would light up a foggy harbor. To actually capture such an eruption of a pre-main sequence star so early in its evolution is an extremely rare occurrence. Often regarded as FU Orionis or EX Lupii type events, these sudden outbursts represent a very elusive stage through which most stars are thought to pass as they make final adjustments with their surroundings before settling down and becoming stable objects much like our very own Sun."

"The idea that this thing, first seen on my 3-inch telescope, which one can easily hold using one hand, would be observed, within 48 hours, by a telescope of 342 tons was absolutely staggering." Jay McNeil

The nebula has been identified on images taken by Evered Kreimer in October 1966, but not in various other images taken between 1951 and 1991. The nebula appears therefore to be very variable in luminosity, and is a reflection nebula illuminated by a variable star of some kind, or with the star's light being variably obscured for some reason.The nebula was not observed after 2004 until 2008, when it reappeared once more.

In November 2018 the Sky & Telescope website reported that the nebula had disappeared. On November 5, an observer using the 500-mm Gemini telescope at the Iowa Robotic Observatory reported its disappearance. Another observer using a 30-inch Dobsonian telescope on November 3 also failed to detect the nebula.>>

[MarkBour]

Re: McNeil's Nebula. Isn't it wonderful to hear of an observer with a 3-inch refractor, looking from his back yard and discovering something like this? Of course he had to be very knowledgeable and astute to have noted it. There is clearly a very massive, extensive, and dark obscuring "cloud" in the immediate area. I agree with the thought that although the variability might be caused by changing output of an infant star, It seems equally possible that the variability of the nebula is due to variable blockage of our view. This hypothesis ought to be verifiable by watching some of those nearby stars. In the two images neufer posted, I can see some changes in and around them, though they are subtle and they may be processing differences. Over time, if some of them wink out or appear, or even just change significantly in brightness, that would give strong evidence of obscuring as the cause. And if none of them ever do, while the nebula continues to vary, that would lend credence to the opposite hypothesis.

[ECA]

I would love...
But know its not possible..
To have a few Lens, that would show at least a few of the colors of the night sky...
Esp viewing without anything, just the naked eye and a handheld lens..

It might scare a few people.
But the atmosphere would cause problems.

[Chris Peterson]

I would love...
But know its not possible..
To have a few Lens, that would show at least a few of the colors of the night sky...
Esp viewing without anything, just the naked eye and a handheld lens..

It might scare a few people.
But the atmosphere would cause problems.

No optics can make the sky appear brighter than it does to the naked eye. Other than the color of the stars, the only way to see color in the sky is with some kind of imaging. The same would be true if you were in space, with no atmosphere. The same would be true if you were closer to an object like this.