A planetesimal orbiting the white dwarf SDSS J122859.93+104032.9

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A planetesimal orbiting within the debris disc around a white dwarf star
https://arxiv.org/abs/1904.02163

Quote :

Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, visible through emission lines. We report a stable 123.4min periodic variation in the strength and shape of the CaII emission line profiles originating from the debris disc around the white dwarf SDSSJ122859.93+104032.9. We interpret this short-period signal as the signature of a solid body held together by its internal strength.