How bright is Tarantula?

[chornedsnorkack]

Any consistent data?
This:
https://en.wikipedia.org/wiki/Tarantula_Nebula
offers +8 over area of 40´x25´.
With even a source: http://www.messier.seds.org/xtra/ngc/n2070.html
This:
https://en.wikipedia.org/wiki/NGC_2070
gives +7,25 over area of just 3,5´x3,5´.
Also with a source: http://simbad.u-strasbg.fr/simbad/si...Ident=NGC+2070

These two sources are utterly impossible. So how much visual light does come from inner 3,5´x3,5´, and how much from outer 40´x25´?

[ngc3314]

I had some data from 2016 taken in Chile which let me measure V magnitudes for various box sizes, using Landolt standard stars to set the photometric zero point. These include the embedded stars as well as nebula.

Box side (arcmin) V
1 8.25
2 7.34
3 6.91
4 6.69
5 6.49
6 6.36
7 6.26
8 6.15

All are centered on the R136 star cluster. These fit with the whole Tarantula being a naked-eye blob in the LMC, since there is additional nebulosity outside this (and the nebula is not well presented in the V filter alone).

[chornedsnorkack]

Thanks a lot!

I had some data from 2016 taken in Chile which let me measure V magnitudes for various box sizes, using Landolt standard stars to set the photometric zero point. These include the embedded stars as well as nebula.

Box side (arcmin); V; Difference to box 1; Ratio to box 1; Extra brightness to last box; Extra area to last box; Surface brightness
1 8.25 0 1 1 1 1
2 7.34 0.89 2.27 1.27 3 0.42
3 6.91 1.34 3.44 1.17 5 0.23
4 6.69 1.56 4.21 0.77 7 0.11
5 6.49 1.76 5.06 0.85 9 0.095
6 6.36 1.89 5.70 0.64 11 0.058
7 6.26 1.99 6.25 0.55 13 0.042
8 6.15 2.10 6.92 0.67 15 0.045

All are centered on the R136 star cluster. These fit with the whole Tarantula being a naked-eye blob in the LMC, since there is additional nebulosity outside this (and the nebula is not well presented in the V filter alone).