In ORFEUS II spectra of the sdO star BD +39 3226 interstellar hydrogen and deuterium is detected .
From Ly \alpha profile fitting and a curve of growth analysis of the Lyman series of H i and D i we derive the column densities N _ { H } = 1.20 ^ { +0.28 } _ { -0.22 } { \cdot } 10 ^ { 20 } cm ^ { -2 } and N _ { D } = 1.45 ^ { +0.50 } _ { -0.38 } { \cdot } 10 ^ { 15 } cm ^ { -2 } .
From the analysis of metal absorption lines in ORFEUS and IUE spectra we obtain column densities for 11 elements .
In addition , we examine absorption lines of H _ { 2 } for rotational excitation states up to J = 7 .
We find an H _ { 2 } ortho-to-para ratio of 2.5 , the fractional abundance of molecular hydrogen has a low value of \log f = -4.08 for a total amount of N ( \mbox { H } _ { 2 } ) = 4.8 ^ { +2.0 } _ { -1.6 } { \cdot } 10 ^ { 15 } cm ^ { -2 } .
The column densities of the excitation states reveal a moderate Boltzmann excitation temperature of 130 K and an equivalent excitation temperature for the excited upper states due to UV pumping of < 1800 K .