1 Delphini is a

shell star A shell star is a star having a spectrum that shows extremely broad absorption lines, plus some very narrow absorption lines. They typically also show some emission lines, usually from the Balmer series but occasionally of other lines. The broad ...

with stable emission lines in the constellation of

Delphinus Delphinus (Pronounced or ) is a small constellation in the Northern Celestial Hemisphere, close to the celestial equator. Its name is the Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-Europea ...

. 1 Delphini consists of three components. 1 Delphini A, the brightest of them, has a magnitude of 6.1; 1 Delphini B located around 0.9 arcsecconds from 1 Delphini A has an apparent magnitude of 8.1; and 1 Delphini C located much farther away at around 17 arcseconds from component A is the faintest with a magnitude of around 14. Due to the stability of the emission lines data from 1 Delphini has been used for developing models of shell stars and

Be star Be stars are a heterogeneous set of stars with B spectral types and emission lines. A narrower definition, sometimes referred to as ''classical Be stars'', is a non-supergiant B star whose spectrum has, or had at some time, one or more Balmer e ...

References

Delphini, 01 Delphinus (constellation) Triple stars 101160 7836 195325 Durchmusterung objects Shell stars A-type giants {{giant-star-stub