Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, The Netherlands and the United Kingdom) and with the participation of ISAS and NASA.

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At 6.0 kpc, 1 $^{\prime\prime}$ = 0.029 pc = $8.95\times 10^{16}$ cm.

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...1997)

The atmosphere models calculations of Sellmaier et al. (1996) have not been confirmed by the Munich group. The spectra from their latest grid of atmosphere models including non-LTE line blocking and blanketing (Pauldrach et al. 2001) predict [Ne III]/ [Ne II] ratios in rough, though somewhat marginal agreement with observations (Giveon et al. 2002, cf. Sect. 5.8).

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... flux

In practice the SED we used in the model is a weighted sum of D4 (70%) and D5 (30%) models from Schaerer & de Koter (1997), i.e. a $2.9\times 10^6$ years old O7 star of 50 $M_{\odot}$ .

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