...(Finkenzeller & Mundt 1984)

Literature values for the distance range from 130 pc (Marraco & Rydgren 1981) to 170 pc (Knude & Høg 1998).

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... here

The fifth one, IRS 3, is located outside the VLA primary beam area and remains undetected at X-ray energies (cf. Nisini et al. 2005).

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... flux

As given in the XMM-Newton User's Handbook V2.2.

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... colours

Adopting ${A_{\rm V}}=15.9 \cdot E(H-K)$ (Rieke & Lebofsky 1985).

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... flares

In the most comprehensive data set on the X-ray emission from young stars, the Chandra Orion Ultradeep Project, only 2% of the optically visible T Tauri stars in the Orion Nebula Cluster showed plasma temperatures exceeding 100 MK (see Preibisch et al. 2005; Getman et al. 2005).

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