Starship Asterisk*

Barnard Stares at NGC 2170

Explanation: A gaze across a cosmic skyscape, this telescopic mosaic reveals the continuous beauty of things that are. The evocative scene spans some 6 degrees or 12 Full Moons in planet Earth's sky. At the left, folds of red, glowing gas are a small part of an immense, 300 light-year wide arc. Known as Barnard's loop, the structure is too faint to be seen with the eye, shaped by long gone supernova explosions and the winds from massive stars, and still traced by the light of hydrogen atoms. Barnard's loop lies about 1,500 light-years away roughly centered on the Great Orion Nebula, a stellar nursery along the edge of Orion's molecular clouds. But beyond lie other fertile star fields in the plane of our Milky Way Galaxy. At the right, the long-exposure composite finds NGC 2170, a dusty complex of nebulae near a neighboring molecular cloud some 2,400 light-years distant.

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Is there a name for the round red bubble in the lower right?

Beyond wrote:Is there a name for the round red bubble in the lower right?

I was wondering the same thing. Seems almost a perfect globe.

Beyond wrote:Is there a name for the round red bubble in the lower right?

I think you mean the red bubble called van den Bergh 70. In this picture, you can see van den Bergh 70 at upper left.

Sidney van den Bergh cataloged

all BD and CD stars north of -33 deg which are surrounded by reflection nebulosity visible on both the blue and red prints of the Palomar Sky Survey.

The van den Bergh catalog contains 159 reflection nebulae.

Reflection nebulae, unlike emission nebula, reflect the light of a star rather than emit their own light. Reflection nebulae are typically blue, but a very few may be another color entirely: the most famous one is the dusty yellow reflection nebula around Antares.

Reflection nebulae are typically found around young stars, often stars of spectral classes B and A. Sidney van den Bergh has cataloged several reflection nebulae in the NGC 2170 complex itself. There are several stars of spectral class B in and near NGC 2170.

The star inside van den Bergh 70 is of spectral class B1, according to my software. A star of that spectral class is just hot enough to ionize a (relatively faint) red emission nebula. Dust in the vicinity of the star reflects the blue light of the star.

Let me say, finally, that today's APOD is glorious! That part of Barnard's Loop really does look like some kind of lumbering red space giant with a huge red nose and a small blue eye, contemplating those baby nebulae and baby stars that he has just discovered! (Will he eat them?)

Ann

The title "Barnard Stares...." hints at something about Barnard's Star, not Barnard's loop.

What about "Barnard Looks....", "Barnard Leers....", "Barnard Glares....", or something else alliterating with "loop" or at least not with "star"?

I would be great to see the whole night sky like this. It shows that there are wonders upon wonders, and that is right in our own neighborhood.
Looking at each section close up is awesome enough, but to see the area all together is just breath taking.

Great Work!

:---[===] *

Raven wrote:The title "Barnard Stares...." hints at something about Barnard's Star, not Barnard's loop.

What about "Barnard Looks....", "Barnard Leers....", "Barnard Glares....", or something else alliterating with "loop" or at least not with "star"?

Tenth magnitude (V=9.54) red dwarf Barnard's Star in constellation Ophiuchus stares at open cluster IC 4665 and red giant star Beta Ophiuchi.

Supergiant star Betelgeuse in Orion is located almost opposite supergiant star Antares in constellation Scorpius. Ophiuchus is a constellation that borders Scorpius. So Barnard's Loop and Barnard's Star are in fact located pretty much opposite one another in the sky. You may confuse them.

Or not.

Ann

Raven wrote:The title "Barnard Stares...." hints at something about Barnard's Star, not Barnard's loop.

Not to me, it doesn't.

I like everything about this APOD, image, text, and links; it connects nicely with one of last week's images in addition to other APODs and the Adams quote is evocative, poetic, and fitting.

owlice wrote:

Raven wrote:
The title "Barnard Stares...." hints at something about Barnard's Star, not Barnard's loop.

Not to me, it doesn't.

"Barnard Stares...." also hints at the Barn Owl Stare:

I'm assuming that the APOD title was simply an inside joke
directed specifically at folks like "Raven."

Only this and nothing more.

Boomer12k wrote:I would be great to see the whole night sky like this. It shows that there are wonders upon wonders, and that is right in our own neighborhood.
Looking at each section close up is awesome enough, but to see the area all together is just breath taking.

Great Work!

This fellow was thinking the same thing! 37,440 exposures later....... Maybe not the whole sky, but at least he captured the Milky Way!
http://skysurvey.org/survey/

Actually, it looks like he captured the entire night sky.

Ann wrote:

Beyond wrote:Is there a name for the round red bubble in the lower right?

I think you mean the red bubble called van den Bergh 70. In this picture, you can see van den Bergh 70 at upper left.

Sidney van den Bergh cataloged.

That would seem to be it. Although it looks more fuller/better in todays APOD.
Thanks, Ann.

That bubble is miles away from the Van den Bergh 70 in the "picture". And it's got very sharp and round edges.

Ann wrote:

Beyond wrote:Is there a name for the round red bubble in the lower right?

I think you mean the red bubble called van den Bergh 70. In this picture, you can see van den Bergh 70 at upper left.

Sidney van den Bergh cataloged

all BD and CD stars north of -33 deg which are surrounded by reflection nebulosity visible on both the blue and red prints of the Palomar Sky Survey.

The van den Bergh catalog contains 159 reflection nebulae.

Reflection nebulae, unlike emission nebula, reflect the light of a star rather than emit their own light. Reflection nebulae are typically blue, but a very few may be another color entirely: the most famous one is the dusty yellow reflection nebula around Antares.

Reflection nebulae are typically found around young stars, often stars of spectral classes B and A. Sidney van den Bergh has cataloged several reflection nebulae in the NGC 2170 complex itself. There are several stars of spectral class B in and near NGC 2170.

The star inside van den Bergh 70 is of spectral class B1, according to my software. A star of that spectral class is just hot enough to ionize a (relatively faint) red emission nebula. Dust in the vicinity of the star reflects the blue light of the star.

Let me say, finally, that today's APOD is glorious! That part of Barnard's Loop really does look like some kind of lumbering red space giant with a huge red nose and a small blue eye, contemplating those baby nebulae and baby stars that he has just discovered! (Will he eat them?)

Ann

vdB70 also has lots of Ha emission nebulosity along with the reflection nebula. A closeup by Adam Block would be amazing!!!

What a beautiful image: I like these views of the night sky!

Seems like I'm not the only one amazed with van den Bergh 70. Got me thinking what it was.