Strange Rhythms, Strange Objects

Advances in instrumentation have uncovered many new phenomena in the universe. Some have been found to repeat, either sporadically or with a more regular period. Many more are suspected to be actually repetitive; they appear as one-off events possibly due to the limitations of the period of observation. These include novaeNova and fast radio burstsFast radio burst. Novae and X-ray burstsX-ray burst are believed to result from accretion in a binary system from a companion star onto a compact object like a white dwarfWhite dwarf or a neutron starNeutron star. Periodic oscillations are found to be associated with sporadic events like Type I X-ray bursts, though their origin is not understood. Fast radio bursts are of varied nature, indicating that origin of different classes may be different.