ИСТИНА

The considerable increase in brightness of the T Tauri star RY Tau was observed in October 1983 - March 1984 during patrol photoelectric UBV observations being carried out since 1965. The optical brightness of the star increased by a factor of 4 in comparison to its mean level for the last few years. In the middle of February 1984 the star brightness rised up to V ≈ 9m.5. At the same time the (B-V) and (U-B) colours became bluer by only 0m.05. Additionally, the infrared JHK photometry and spectroscopic observations of RY Tau in the wavelength range of λλ3600 - 5000 Å and Hα were carried out during the maximum light. The star became brighter also in the infrared. The authors estimate the spectral type of RY Tau at maximum light of about G5.