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We report the discovery of a rare close binary system, SMSS J160639.78-100010.7, comprised of a magnetic white dwarf with a field of about 30 MG and a brown dwarf. We measured an orbital period of 92 min which is consistent with the photometric period. Minimum and maximum light occur at the orbital quadratures Phi=0.25 and 0.75, respectively, and cannot be caused by reflection on the brown dwarf, but, instead, by a spot on the synchronously rotating magnetic white dwarf. The brown dwarf does not fill its Roche lobe and the system may be in a low-accretion state or, more likely, in a detached state following episodes of mass transfer. SMSS J160639.78-100010.7 is the nearest known magnetic white dwarf plus brown dwarf system.
We observed the 2012-2013 superoutburst of the newly identified transient SSS J122221.7-311523 and found that this object showed successive two superoutbursts. Superhumps grew in amplitude during the second superoutburst and showed a characteristic p
We report on photometric observations of two dwarf novae, OT J075418.7+381225 and OT J230425.8+062546, which underwent superoutburst in 2013 (OT J075418) and in 2011 (OT J230425). Their mean period of the superhump was 0.0722403(26) d (OT J074518) an
We report the identification of the bright (V${sim}13.3$ mag) star FY Sct as a long period detached eclipsing binary using a combined ASAS-SN and ASAS light curve spanning 2000-2018. The orbital period is P${sim}2.57$ years and the primary eclipse la
Building on previous work, a new search of the SuperWASP archive was carried out to identify eclipsing binary systems near the short-period limit. 143 candidate objects were detected with orbital periods between 16000 and 20000 s, of which 97 are new
We report the discovery of SMSS J160540.18-144323.1, a new ultra-metal poor halo star discovered with the SkyMapper telescope. We measure [Fe/H] = -6.2 +- 0.2 (1D LTE), the lowest ever detected abundance of iron in a star. The star is strongly carbon