We present optical photometric observations of SN 2018aoq from 2 to 100 days after explosion, and 7 spectra at epochs from 11 to 71 days. The light curves and spectra are typical for SNe II-P. As previously reported, SN 2018aoq appears to be of intermediate brightness between subluminous and normal SNe II-P. SN 2018aoq was discovered in Seyfert galaxy NGC 4151, for which the distance is uncertain. We utilised the Expanding Photosphere Method using three sets of filter combinations and velocities derived from the absorption minima of FeII lines and obtained a distance of 20.0±1.6 Mpc. The Standard Candle Method applied to SN 2018aoq yields a distance of 16.6±1.1 Mpc. Both values are consistent with the distance measurements for NGC 4151 based on geometric method.

Context. Long timescale periodic variations in T Tauri stars may be related to changes in their protoplanetary disks. Aims. A lengthy homogeneous series of spectral observations of the CTTS T TauN has been analyzed. Methods. We search for periodicity in the equivalent widths of the emission lines in the optical and in the UV. Results. Significant periodic variation is found in the equivalent widths of Hβ and CaII emission features on a time scale of 33 ± 1.5 days. Variations in the UV emission lines based on archival IUE spectra are also consistent with this period. Conclusions. This is clearly not the rotation period of the star, which is known to be 2.8 days, and must arise somewhere in the magnetosphere, disk or outflow region.

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