by neufer » Fri Jan 28, 2022 10:42 pm
Chris Peterson wrote: ↑Fri Jan 28, 2022 8:00 pm
dlmartin7@cogeco.ca wrote: ↑Fri Jan 28, 2022 6:48 pm
With Ann and Peterson sparing, one can only conclude that this discussion is one for the ages.
But we're not. We're in agreement.
- Indeed.... for you wrote:
Chris Peterson wrote: ↑Thu Jan 27, 2022 5:48 pm
I'm mainly responding to her claim "It is so clear from the Hubble image that NGC 1999 is a cavity." I guess that is subject to interpretation. If she means it as "the dark region in NGC 1999 is a cavity, not a dust cloud", then there is no disagreement.
So...
it was clear to you both from the Hubble image alone that this was never a
Bok globule (and, presumably, that Herschel PACS far-IR 70 & 160mum maps, APEX LABOCA & SABOCA submillimeter continuum maps, and Magellan PANIC near-IR images were a waste of time)
https://arxiv.org/abs/1005.2202 wrote:
Hier ist wahrhaftig ein Loch im Himmel - The NGC 1999 dark globule is not a globule
T. Stanke, A. M. Stutz, J. J. Tobin, B. Ali, S. T. Megeath, O. Krause, H. Linz, L. Allen, E. Bergin, N. Calvet, J. Di Francesco, W. J. Fischer, E. Furlan, L. Hartmann, T. Henning, P. Manoj, S. Maret, J. Muzerolle, P. C. Myers, D. Neufeld, M. Osorio, K. Pontoppidan, C. A. Poteet, D. M. Watson, T. Wilson
[Submitted on 12 May 2010]
The NGC 1999 reflection nebula features a dark patch with a size of ~10,000 AU, which has been interpreted as a small, dense foreground globule and possible site of imminent star formation. We present Herschel PACS far-infrared 70 and 160mum maps, which reveal a flux deficit at the location of the globule. We estimate the globule mass needed to produce such an absorption feature to be a few tenths to a few M
sun. Inspired by this Herschel observation, we obtained APEX LABOCA and SABOCA submillimeter continuum maps, and Magellan PANIC near-infrared images of the region. We do not detect a submillimer source at the location of the Herschel flux decrement; furthermore our observations place an upper limit on the mass of the globule of ~2.4x10
-2 M
sun. Indeed, the submillimeter maps appear to show a flux depression as well. Furthermore, the near-infrared images detect faint background stars that are less affected by extinction inside the dark patch than in its surroundings. We suggest that the dark patch is in fact a hole or cavity in the material producing the NGC 1999 reflection nebula, excavated by protostellar jets from the V 380 Ori multiple system.
[quote="Chris Peterson" post_id=320215 time=1643400032 user_id=117706]
[quote=dlmartin7@cogeco.ca post_id=320210 time=1643395689]
With Ann and Peterson sparing, one can only conclude that this discussion is one for the ages.[/quote]
But we're not. We're in agreement.[/quote]
[list]Indeed.... for you wrote:[/list]
[quote="Chris Peterson" post_id=320185 time=1643305698 user_id=117706]
I'm mainly responding to her claim "It is so clear from the Hubble image that NGC 1999 is a cavity." I guess that is subject to interpretation. If she means it as "the dark region in NGC 1999 is a cavity, not a dust cloud", then there is no disagreement.[/quote]
So... [b][u]it was clear to you both [color=#FF0000]from the Hubble image alone[/color][/u][/b] that this was never a [url=https://en.wikipedia.org/wiki/Bok_globule]Bok globule[/url] (and, presumably, that Herschel PACS far-IR 70 & 160mum maps, APEX LABOCA & SABOCA submillimeter continuum maps, and Magellan PANIC near-IR images were a waste of time) :?:
[quote=https://arxiv.org/abs/1005.2202]
[b][size=125]Hier ist wahrhaftig ein Loch im Himmel - The NGC 1999 dark globule is not a globule[/size][/b]
T. Stanke, A. M. Stutz, J. J. Tobin, B. Ali, S. T. Megeath, O. Krause, H. Linz, L. Allen, E. Bergin, N. Calvet, J. Di Francesco, W. J. Fischer, E. Furlan, L. Hartmann, T. Henning, P. Manoj, S. Maret, J. Muzerolle, P. C. Myers, D. Neufeld, M. Osorio, K. Pontoppidan, C. A. Poteet, D. M. Watson, T. Wilson
[Submitted on 12 May 2010]
The NGC 1999 reflection nebula features a dark patch with a size of ~10,000 AU, which has been interpreted as a small, dense foreground globule and possible site of imminent star formation. We present Herschel PACS far-infrared 70 and 160mum maps, which reveal a flux deficit at the location of the globule. We estimate the globule mass needed to produce such an absorption feature to be a few tenths to a few M[sub]sun[/sub]. Inspired by this Herschel observation, we obtained APEX LABOCA and SABOCA submillimeter continuum maps, and Magellan PANIC near-infrared images of the region. We do not detect a submillimer source at the location of the Herschel flux decrement; furthermore our observations place an upper limit on the mass of the globule of ~2.4x10[sup]-2[/sup] M[sub]sun.[/sub] Indeed, the submillimeter maps appear to show a flux depression as well. Furthermore, the near-infrared images detect faint background stars that are less affected by extinction inside the dark patch than in its surroundings. We suggest that the dark patch is in fact a hole or cavity in the material producing the NGC 1999 reflection nebula, excavated by protostellar jets from the V 380 Ori multiple system. [/quote]